Abstract Book - physics.unipune.ac.inphysics.unipune.ac.in/~rmc/2019/RMC2019_Abstract_book.pdf · PP-6 Pooja Galande Study of Cu2O Thin Film Synthesis by Electrochemical Deposition

Abstract Book

25th

Raman Memorial Conference

“Physics of 2D Materials: Theory and Experiments”

14th- 15th February,2019

Organized by,

Research Students,

Department of Physics,

Savitribai Phule Pune University, Pune, India.

ABSTRACT BOOK

25th Raman Memorial Conference

rmc - 2019 14th– 15th February,2019

Organized by,

Reasearch Students,

Department of Physics,

Savitribai Phule Pune University,

Pune, India.

25th

Raman Memorial Conference 2019

3

Our

Sponsors

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Sharad Agency

Ambai Computers

Universal Traders

Ashish Marketing

Anna Canteen

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Foreword from Head of the Department

I am very happy to write this foreword on the occasion of the Raman Memorial

Conference 2019 taking place on 14th & 15th February, 2019 in the Department of Physics,

S. P. Pune University. This year is very special as it is the silver jubilee of this conference as

it is being conducted in our Department continuously since 1994. Raman Memorial

Conference is one of the most important events conducted in the department. The most

special feature of this conference is that it is ‘of the students’, ‘by the students’ and ‘for the

students’. Hence, it is very important for the students not only from the point of view of

gaining knowledge but also for getting trained to take up administrative responsibilities. I am

confident that RMC 2019 will lead to dissemination of knowledge about latest research and

give rise to fruitful interactions amongst the delegates. I wish RMC 2019 grand success.

Prof. S. W. Gosavi

Head, Department of Physics

S. P. Pune University

Pune

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Conference Theme

Physics of 2D Materials: Theory and Experiments

The rise of research in two-dimensional (2D) materials began after the isolation

of graphene in the year 2004. The abundance of properties, combined with the

highest achievable surface-to-volume ratio, render 2D nanomaterials suitable

for advanced applications in several areas, such as material science, physics,

chemistry, engineering, biology, pharmacy and medicine. Current research

trends in 2D nanomaterials offer plenty of opportunities to study electronic,

optical, thermal, mechanical, vibrational, spin and plasmonic properties. The

development of new applications in particular, the novel top-down or bottom-

up approaches to create new materials, is endless.

The scope of RMC 2019 “Physics of 2D Materials: Theory and

Experiments” is to provide a platform for presenting the state-of-the-art

knowledge of research on the properties, novel synthesis techniques,

characterization and applications of 2D nanomaterials into electronic, optical,

or electrochemical devices, as well as to cover the current challenges related to

them.

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LOCAL ORGANIZING COMMITTEE

Mr. Akash Jadhav

Mr. Akshay Vyas

Mr. Ambadas Phatangare

Mr. Amish Parmar

Mr. Amol Deore

Mr. Gaurav Bholane

Mr. Md Samsuzzaman

Ms. Priyanka M

Mr. Rohit Kumar

Ms. Shrreya Krishnamurthy

Ms. Sneha Kandare

Mr. Tulshidas Darvade

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Table of Content

ID No. Author and Title of Paper

Keynote Prof. Bodh Raj

Mehta KPFM based nanoscale investigations of 2D-3D interfaces

IT-1 Dr. Nirmalya Ballav

Chemically Derived Reduced Graphene Oxide for Energy Applications

IT-2 Prof. Pratap Raychaudhuri

Observation of hexatic vortex fluid in a thin superconducting film

IT-3 Dr. Suwarna Datar

Nanowire Gap- Plasmon’s assisted Raman Scattering

IT-4 Dr. Vasant Sathe

Polarized Raman scattering of 2-D structures

IT-5

Prof. Rudolf Holze

Supercapacitors: From the Leyden Jar to Supercap Trams and Busses-Past and

Perspectives

TP-1

Vishal Bharud

Measurement of Cross Sections for formation of Metastable states and

Radioisotopes of a few Nuclei through Nuclear Reactions induced by

Bremsstrahlung Radiation and Neutrons

OP-1

Abhishek Pandey

3D Oxidized Graphene Frameworks for Efficient Filtration of Methylene Blue

Dye

OP-2 Mihir Durve

Learning to Flock, Flocking to Learn

OP-3 Indranil Roy

Origin of pseudo-gapped vortex core: an example of Quantum fluctuation

OP-4 Farsa Ram

Organic Flexible Nanogenerators for Mechanical Energy Harvesting

OP-5

Suyog Raut

Mechanical vibration damping by thermal plasma synthesized iron oxide

nanoparticles

OP-6 Sameer Salunkhe

Multi-frequency Radio Study of the Galaxy Cluster Abell 2744

OP-7 Bhagyashri Shinde

Model for growth, transport and morphology of fungal hyphae

OP-8

Swati Parmar

Structural and Electrical Properties of 2D/2D MoS2-hBN Mosaic Structure and

Trieboelectric Nanogenerator Application

OP-9 Sushant Sahu

Visible-to-Ultraviolet Upconversion Sensitized Photocatalysis: Fact or Fiction?

OP-10

Sudip Kumar Kundu

Computation of flood-drought year by using IMD monthly rainfall data over

Gangetic plain

OP-11

Sushmita Rath

Design and Development of Quartz Tuning Fork based Sensor Array for

Metabolic Rate monitoring

OP-12 Yogesh Shinde

Synthesis of Platinum Decorated RGO-TiO2 (P25) Composites for Enhanced

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Photocatalytic Hydrogen Evolution and Dye Degradation

OP-13 Hemlata Bhandari

Light-cone and front dynamics of single particle extended quantum walk

OP-14

Shalaka Kamble `

Thermionic emission measurement of refractory materials using indigenously

developed thermionic emission measurement set up

OP-15 Onkar Ramdasi

Ferroelectric, Dielectric and Piezoelectric Properties of Hf Modified BaTiO3

OP-16

Sachin Wadhai

Synthesis of Highly Efficient Metal Free Phosphorus doped Graphitic Carbon

Nitride / P25 (TiO2) Composite for Visible Light Photocatalytic Hydrogen

Evolution

OP-17

Ambadas Phatangare

Development of Nuclear battery using Tritium gas filled tubes and Photovoltaic

devices

OP-18

Swapnil Doke

Sustained multiferroicity in liquid crystal induced by core/shell geometry of

quantum dots

OP-19 Kishor Gavhane

Dosimetric properties of BaF2:X (X= Gd, Yb and Ce) phosphor for -ray

OP-20

Supriya More

Proliferation of Human Mesenchymal Stem cells on UHMWPE polymer surface

as an effect of plasma processing

OP-21

Prachi Ghoderao

Development of Antibiotic-Magnetic Carbon Nanovectors Complexes for

Enhancing Efficacy of the Antibiotic

OP-22 Shrreya Krishnamurthy

Designing white light emitting phosphors using 2D hybrid perovskites

OP-23

Imran Shaikh

Spin coated Ag nanoparticles as a SERS substrate for trace detection of food

adulterant melamine in the milk powder

OP-24

Neha Ghodke

Synthesis of Ni nanoparticles by thermal plasma method and their implementation

for hydrogen production from alkaline sodium borohydride solution

OP-25

Theodore Selwyn

Statistical model analysis of neutron induced reactions on 232

Th from reaction

threshold to 20 MeV for ADSS application

PP-1

Aparna Ukarande

CdS thin films grown by electrodeposition techniques as a buffer layer for solar

cell application.

PP-2

Prerna Unadkat

Coffee-ring Effect assisted, Surface modification Free Paper-based Colorimetric

Glucose Sensor

PP-3 Sujay K Kirdavkar

ArVirInd-A database of Arbo-Viruses from India

PP-4 Aditi Awate

Synthesis of γ-Fe2O3/rGO nanocomposite and its application as Supercapacitor

PP-5 Avinash A Patil

Meteorological parameters modulate Chikungunya and Dengue occurrences in

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India (2010-2016)

PP-6

Pooja Galande

Study of Cu2O Thin Film Synthesis by Electrochemical Deposition Method for

Solar Cell Application

PP-7 Vaibhav Walve

Hafnia based gate dielectrics for MOS-FET

PP-8

Aditi Dave

Synthesis And Characterization of Graphene Oxide and Reduced Graphene Oxide

for Gas Sensing Study

PP-9

Chetan Chavan

Study of structural, electronic and magnetic properties of pure and doped

(Fe2O3) n cluster

PP-10

Kiran Shinde

Synthesis of Nano-Crystalline CdS thin films by using Hot Injection method For

Harvesting Solar Radiation

PP-12

Supriya Koyale

Incorporation of Chemically Synthesized Cadmium Sulfide nanoparticles on ZnO

nanorods for to fabricate photoelectrode

PP-13

Sachin Desarada

Effect of RTP annealing on CIGS thin film deposited from single-step, low-cost

electrochemical technique

PP-14

N.D.Desai

Enhanced photoelectrochemical performance of Bi2Se3 Thin Films: Effect of

Surfactant

PP-15 Novman Nabeel

Conductive Polypyrrole as a Ammonia Gas Sensor

PP-16

Poonam Lawand

Study of effect of molarity of sulfur source on Cadmium Sulfide

nanoparticles synthesized by using chemical precipitation method

PP-17

Sakshi Patil

Structural and Morphological Properties of Electrodeposited Bismuth Telluride

(Bi2Te3) Thin Films.

PP-18

Suhail A. A. R. Sayyed

Design and Development of low cost Arduino based Successive Ionic Layer

Adsorption and Reaction (SILAR) Coating System with magnetic stirrer using

discarded Lab Equipments

PP-19 Varsha Pawane

Co-deposited Sn-Ag- Cu films for Fine Pitch Surface finishes in PCBs

PP-20

Priyanka Bhosale

Synthesis and Characterization of L-Histedine modified biocompatible

ZnO Nanoparticles

PP-21 Deepesh Bhamre

Equivalence of One Loop Feynman Diagrams in Covariant and Light-Front QED

PP-22

Dipmala Sali

Synthesis and Characterisation of CdTe thin films prepared by electrochemical

technique

PP-23 Shital D. Satpute

Fabrication of bilayer ZnO Compact/ZnO/In2O3 using SILAR method

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PP-24

Hakim Rizwan

Structural, Optical and Gas Sensing Properties of Spray Deposited

Sn doped MoO3 Thin Films

PP-25

Shraddha Mahakal

Synthesis, characterization & bacterial activity of ZnO and Serine modified ZnO

nanostructures

PP-26 Minal kurane

Heart Rate Variability Analysis

PP-27 Tejal Meharwal

Fe3O4/rGO nanocomposite and its Application

PP-28

Arun Jaiswal

Effect of Photo-initiator Concentration on the Structural Resolution in Two-

Photon Lithography

PP-29

Ashvini Punde

Study of soft (pre) annealing temperature effect on sputtered tri-layer precursor

CZTSthin film absorber for Photovoltaic’s

PP-30 Pratibha Pate

Characterization of Hydrothermally Synthesized MoSe2 Nanoparticles

PP-31

Ashwini Datar

Magnetic force microscopic analysis of the composite film of PLZT and CZFO

synthesized by Sol gel technique

PP-32

Mamta Nasane

The role of sulfurization temperature on sputtered CZTS thin film absorber for

Photovoltaic’s

PP-33

Siddharth Karkhanis

Synthesis, characterisation and applications of a versatile coordination complex –

potassium trioxalato ferrate (iii) trihydrate

PP-34 Sunita Pawar

SILAR Deposited ZnO Nanorods for Biomedical Application

PP-35 Sweta Rath

Design and Development of a Resonator based Bio-sensor for bacteria detection

PP-36

Poonam Borhade

Raman Investigations on Graphite, Graphene Oxide (GO) and reduced Graphene

Oxide (rGO)

PP-37

Sandhya Wakhare

Structural and Optical Properties of Indium doped ZnO monolayer : Density

Functional Study

PP-38

Shilpa U

Reinforced Reduced Graphene Oxide Sheets as Materials for EMI Shielding in Ku

Band

PP-39

Vaishnavi Chothe

To study electronic properties of graphene using Density functional theory as

implemented in Quantum Espresso

PP-40

Shivaji Sonawne

Deposition and Characterization of Zinc Telluride thin film as Interface Layer for

CdTe Solar cells

PP-41 Mangesh Desai

Excellent supercapacitive performance of ZnO@MnO2 nanostructures

PP-42 Anuja Gore

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Synthesis and Characterization of PbO nanostructures by Hydrothermal Method

PP-43 Supriya Moholkar

Study of Novel SrDy2O4:Eu phosphor for Thermoluminescence Dosimetry

PP-44 Akash Bhoir

Thermoluminescence studies of Co-60 - ray irradiated BaB4O7:Ce

PP-45

Mahesh Gaikwad

Synthesis and characterization of Zinc Oxide nanoparticles by Simple

Precipitation method in aqueous media.

PP-46

Kalyani Annadate

Study of growth and properties of Pure and CaCO3 doped Triglycine Sulphate

(TGS) crystal by solution growth method

PP-47

Monika Joshi

Facile aqueous route for the synthesis of Cu2SnS3 thin films for

Photoelectrochemical solar cell application

PP-48

Amish Parmar

Use of TiO2 nanotube arrays with sandwich structure on Nickel for betavoltaic

nuclear battery

PP-49 Bhakti Kshirsagar

Pressure dependent ferroelectric proprties of LaWN3

PP-50

Akshay Vyas

Studies on ethanol electrooxidation over metal nanoparticles grown using

successive ionic layer adsorption and reaction method

PP-51 Akshay Sonavane

Comparative study of ZnS thin films grown by MA-CBD and M-CBD methods

PP-52 Pankaj Bhujbal

Studies on the Influence of RF Power on Al doped ZnO Thin Films

PP-53

Chaitali Pawase

Synthesis and characterization of graphene based hybrids for nonvolatile memory

devices such as RRAM

PP-54

Tulshidas C. Darvade

Structural Ferroelectric and Dielectric properties of lead free Ba0.97Ca0.03TiO3

electroceramic

PP-55

Sandhya Gadge

Synthesis and Characterization of CeO2 nanostructures for the catalytic

degradation of methylene blue

PP-56

Sarika Jadhav

Synthesis and Characterization Graphene based Metal oxide nanocomposite for

Energy Storage Application

PP-57

Kalyani Tikote

Synthesis and Field Emission Study of MoO3 (Molybdenum Trioxide)

Nanostructures

PP-58

Mayuri T. Jagdale

Synthesis and Size Control of Silver Nanoparticles using Low Energy Ar-Ion

Irradiation

PP-59

Aditi R. Kulkarni

Excellent supercapacitive performance of marigold like nanostructures of

Manganese dioxide

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PP-60

Sneha Kandare

Inelastic Neutron Scattering and Lattice Dynamics of Cu2ZnSnS4

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Invited

Talks

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KPFM based nanoscale investigations of 2D-3D interfaces

Prof. Bodh Raj Mehta

Thin Film Laboratory, Department of Physics, Indian Institute of Technology Delhi, Hauz

Khas, New Delhi-110016, India.

Email: [email protected]

Abstract:

Junctions between two dissimilar materials have been a topic of significant research interest

due to novel interface physics and its direct importance on device performance due to the

influence of defect states, structural and electronic discontinuities. Due to atomically thin

semiconductor layer in 2D-3D semiconductors, investigating and understanding the nature of

interface and its influence on the device characteristics becomes even more complex and

intriguing. In this presentation, the influence of 2D-3D interfaces on the device characteristics

of G-Si solar cell, MoS2-ZnS intermediate band gap semiconductor and MoS2-Bi2Te3

thermoelectric devices will be discussed. In the first example, graphene layers prepared by

CVD method have been used as a top layer in p-n silicon junctions and an increase in

efficiency from 5.3% to 8.9% is observed. Surface potential changes at the graphene -Si

junctions in surface and junction modes have been examined using Kelvin probe force

microscopy investigations. Voc nanoscale maps derived from these measurements show that

topographical impurities and wrinkled boundaries on the graphene surface affect affecting

junction performance. In another study, patterned MoS2 2D layers having feature size varying

from 10 um to 1 um have been grown by a combination of stencil lithography and magnetron

sputtering technique. Composite layers having wide band gap ZnS films and 2D MoS2 layers

show increased interface voltage due to 2D character. In the third example, the influence of

n-n and n-p interfaces in MoS2-Bi2Te3 and MoS2-Sb2Te3 devices on the electron and phonon

scattering resulting in improved thermoelectric properties will be discussed. It is shown that

due to limited thickness of the 2D layer, there is a large accumulation of charge at the surface

which modifies the current transport across the junction. These results are very important for

understanding the basics physics issue related to 2D materials based junctions.

mailto:[email protected]

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Chemically Derived Reduced Graphene Oxide for Energy Applications

Dr. Nirmalya Ballav1,2

1 Department of Chemistry, Indian Institute of Science Education and Research (IISER), Dr.

Homi Bhabha Road, Pune 411 008, India.

2 Centre for Energy Science, Indian Institute of Science Education and Research (IISER), Dr.

Homi Bhabha Road, Pune 411 008, India.

E-mail: [email protected]

Abstract:

Graphene-based materials are emerging in the development of energy devices, specifically

for commercial supercapacitor. Recently, we have introduced transition metal salts as

effective reducing agents for the chemical reduction of graphene oxide (GO) whereby

semiconducting reduced graphene oxide (rGO) materials with various morphological patterns

(two-dimensional nanosheet and three-dimensional mesoporous structures) are isolated.[1,2]

The fabricated all-solid-state supercapacitor of as-synthesized rGO exhibited significantly

higher specific capacitance (>300 F/g at 1 A/g), remarkable cycling stability (>80% retention

of capacitance beyond 100,000 continued charge-discharge cycles), and flexibility (>500

bending cycles), which are overall comparatively much better than those of rGO derived from

conventional reducing agents like NaBH4 and N2H4. Use of organic electrolyte further

boosted the supercapacitor performance. Our work opens up new possibilities for the

production of rGO on an industrial scale satisfying the needs of high-performance energy-

storage devices. Introducing an interfacial layer of rGO in dye sensitized solar cell, we are

also being able to significantly enhance the efficiency.

References

1. P. K. Jha and N. Ballav, Complete Filing of Indian Patent (Application No.

201621023063).

2. P. K. Jha, S. K. Singh, V. Kumar, S. Rana, S. Kurungot, and N. Ballav, Chem 3

(2017), 846.


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Observation of Hexatic Vortex Fluid in a Thin Superconducting Film

Prof. Pratap Raychaudhuri

Department of Condensed Matter Physics and Materials Science, Tata Institute of

Fundamental Research (TIFR), Mumbai 400 005, India.


Abstract:

In 1969, working on a theoretical problem out of pure mathematical curiosity, David

Thouless stumbled upon a new kind of phase transition, across which physical properties

show abrupt change but the free energy varies smoothly. Very soon, Michael Kosterlitz and

David Thouless realized that this kind of phase transition could be ubiquitous across 2-

dimensional (2D) systems. For the particular case of a 2-dimensional crystalline solid, the

(Berezinski)-Kosterlitz-Thouless (BKT) theory predicts that the solid melts via a novel

intermediate state, called the hexatic fluid, which possesses the orientational order of a solid

but the flow properties of a fluid. Over the years there have been several attempts to test the

BKT theory in diverse 2D systems such as electrons over a liquid He surface, inert-gas

monolayers adsorbed on graphite, vortices in superconducting thin films and colloidal

crystals, but unambiguous identification of hexatic fluid phase has been very few. Indeed,

according to the various experimental conditions one can either prove the occurrence of the

melting transition at the expected value, or the existence of an orientational order when the

translational one is lost, but the simultaneous observation of the two features has so far been

available only in the case of some magnetic colloidal crystals. Recently, using a combination

of real space imaging and transport measurements we unraveled the hexatic vortex fluid state

in a thin film of the amorphous superconductor, MoGe [1]. In this talk I will discuss the

properties of this hexatic vortex fluid, and present results that points towards the possibility

of this state being a quantum fluid. I will also contrast the hexatic vortex fluid with the

hexatic glass observed in more disordered superconductors.

Reference

1. I. Roy et al, arXiv:1805.05193 (to appear in Phys. Rev. Lett.)


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Scanning Probe Microscopy (SPM) studies of 2D Materials

Dr. Suwarna Datar

Department of Applied Physics Defense Institute of Advanced Technology (DIAT), Pune 411

025, India.


Abstract:

Scanning Probe Microscopy (SPM) is a unique tool to understand different properties of

materials at nanoscale. Each mode of SPM offers unique capability to understand various

aspects of material properties like morphological, magnetic, electrostatic, thermal,

piezoelectric etc. at nanoscale.

Scanning Tunneling Microscopy/Spectroscopy (STM)/(STS) is used to study information

about Local Density of States (LDOS) which can be used to understand edge states of 2D

materials. Electrostatic Force Microscopy (EFM) has been proven to be effective to evaluate

layer numbers in 2D structures. By measuring surface potential or work function using EFM,

this technique can be used for identify different regions if combination of two different 2D

structures is made. Some recent studies on 2D materials using different modes of SPM will

be discussed.


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Polarized Raman scattering of 2-D structure

Dr. Vasant Sathe

UGC-DAE Consortium for Scientific Research, University Campus, Indore 452 001, India.


Abstract:

Raman spectroscopy has emerged as a very powerful tool to characterize nano structures and

2-D materials. Polarized Raman spectroscopy adds to the power and provides directional

information about the 2-D structures like carbon nano tubes, Graphene and epitaxial thin

films. In this lecture the basics of Raman spectroscopy and analysis of the Raman mode using

polarized Raman spectroscopy will be described. The power of Polarized Raman

spectroscopy in obtaining information about Raman Tensors of epitaxy of thin films and

single crystals will be elaborated. Several examples will be given illustrating the effect of

dimensionality reduction, strain, and particle size reduction on Raman spectra. The effect of

anomalous changes in the lattice parameter of NdGaO3 single crystal substrate as a function

of temperature will be shown to be directly reflected in the phonon structure. The epitaxial

nature of CuO thin films is deduced using polarized Raman scattering. The effect of magnetic

order on the phonon structure in this system will be discussed. The local domain structure of

a strain free, 150 nm thick, epitaxially grown single crystalline thin film of CaCu3Ti4O12 is

probed by polarized Raman spectroscopy. The polarization dependence of the Raman

intensities of the observed bands as a function of varying angle between the domain axes and

the polarization vector of the scattered laser photon is measured. Theoretical formulations

involving the Raman tensor are presented, which enable determination of the domain

structure from the observed polarized Raman spectra, and a singlecrystal-like domain

structure is found. The Raman tensor elements and domain orientation direction were

determined by fitting the observed Raman intensities with theoretical calculations and by

carrying out Raman mapping of the film. Our data show an absence of twin domain structure

and twin domain boundaries in the single-crystal-like epitaxial thin films of CaCu3Ti4O12.


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Thesis

Presentation

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Measurement of Cross Sections for formation of Metastable states and

Radioisotopes of a few Nuclei through Nuclear Reactions induced by

Bremsstrahlung Radiation and Neutrons

Vishal D. Bharud, V.N. Bhoraskar, S.D. Dhole

Microtron/Neutron Lab, Department of Physics, S.P. Pune University, Pune, India- 411007, Presenting author: [email protected]/[email protected]

Abstract:

The thesis reports studies on the measurement of cross sections for formation of metastable

and ground states of a few nuclei through nuclear reactions. The nuclear reactions were

induced by 6 MeV to 15 MeV photons and 13.6 MeV to 14.8 MeV energy neutrons. In

addition, the covariance analysis for efficiency calibration for HPGe and NaI(Tl) detector

using standard sources has been introduced. The spectra of the gamma ray were measured by

using Canberra/ORTEC HPGe and NaI(Tl) detectors system coupled to a PC-based 2K

channel MCA. The Standard radioactive sources such as Ba-133, Na-22, Co-60, and Cs-137

are used for the efficiency calibration. The standard activation methods was employed to

measure the cross sections based on the measurement are induced gamma-ray activity in the

photon and neutron irradiation samples. The experimental measured cross sections are found

in good agreement with the corresponding theoretical cross sections estimated by TALYS-1.8

and EMPIRE-II-3.2. Malta nuclear codes.

References:

1. Handbook on photonuclear data for the applications: cross sections and spectra IAEA,

Vienna 2000 IAEA-TECDOC-1178 ISSN1011-4289.

2. Attar, F. M. D, Measurement of activation and metastable state cross-sections of a

few nuclear reactions induced by neutrons of 13.6 to 14.8 MeV energies,

http://hdl.handle.net/10603/125996.

3. Y. Santhi Sheela, H. Naik , K. Manjunatha Prasad, S. Ganesan, N. Sreekumaran Nair

and S. V. Suryanarayana, Covariance analysis of efficiency calibration of HPGe

detector. Internal Report No. MU/STATISTICS/DAE-BRNS/2017/1, 19-February-

2017.

http://hdl.handle.net/10603/125996

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Oral

Presentation

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3D Oxidized Graphene Frameworks for Efficient Filtration of Methylene

Blue Dye

Abhishek Pandeya, Madhurima Deb

a , Pranav Bhagwan Pawar

a, Sumit Saxena

a, and

Shobha Shuklaa

aIndian Institute of Technology , Bombay, Powai, Mumbai, MH, 494661

Presenting author: [email protected]

Abstract:

Textile industries dispose of their waste dyes in water bodies; these organic molecules are

very toxic to the environment. These waters are unfit for drinking and irrigation purpose.

Many adsorbents have been used for removing these dyes from waste water, but they are

expensive and slow. Graphene oxide due to its high surface area and chemical properties is

widely used for water purification. Graphene oxide has several functional groups such as

hydroxyl, epoxy, carboxyl etc., these functional groups support water to pass and obstruct the

other waste particle and molecules by trapping and adsorbing them. We have investigated the

performance of 3D oxidized graphene framework (OGF) for filtration of methylene blue dye.

It has been observed that these3D OGF works significantly for methylene blue with removal

efficiency near 99.7%, we have also studied the filtration efficiency with different parameters

such as concentration of dye, pH of dye solution, and flow rate through the 3D OGF. The

flow rate as high as 480 Lm-2

hr -1

is achieved without any external pressure difference

removing more than 99% of dye. This 3D OGF can be used for fast and efficient removal of

cationic dyes disposed from industries.

25th


25

Learning to Flock, Flocking to Learn

Mihir Durve1,2

, Fernando Peruani3 and Antonio Celani

2

1Department of Physics, University of Trieste, Trieste, Italy-34127

2Quantitative Life Sciences, The Abdus Salam International Centre for Theoretical Physics,

Trieste, Italy. 34151

3Lab. J.A.Dieudonne, Universite Nice Sophia Antipolis, Nice,

France 06108

Abstract:

Aggregation is seen in many species in animal kingdom. Fish form schools, birds flock,

bacteria form colonies etc [1]. When animals aggregate, they can also exhibit collective

behavior such as moving in a coordinated fashion. Spectacular display flocking by few

thousand sterlings birds is just one such examples. The reasons behind the collective behavior

varies from foraging efficiently to confuse the predators attacking the flock [2]. We study

aggregation of agents in such systems by treating the agents as decision makers. We

implement reinforcement learning techniques [3] to study the optimum decision making by

these agents in multi-agent system. This decision making process maximizes the reward

which encourage aggregation of agents.

25th


26

Origin of pseudo-gapped vortex core: an example of Quantum fluctuation

Indranil Roya, Surajit Dutta

a, Soumyajit Mandal

a, John Jesudasan

a, and Pratap

Raychaudhuria

aTata Institute of Fundamental Research, Homi Bhabha Road, Colaba, Mumbai 400005, India


Abstract:

When a type-II superconductor is subjected to a magnetic field larger than its lower critical

field, magnetic field lines enter the superconductor in forms of vortices, where each field line is

surrounded by a circulating supercurrent. In tunneling experiments, such as, Scanning Tunneling

Spectroscopy (STS), the superconducting state is identified by the presence of a gap in differential

conductance (dI/dV) which is proportional to the superconducting Local Density of States (LDOS). In

the same measurement a vortex core is identified by a flat differential conductance, similar to a

normal metal or the presence of a localized peak in differential conductance inside the core due to

Andreev bound states. This phenomenon is regularly observed in 3-dimensional superconductors,

such as NbSe2.

Reecently, in thin films of NbN [1] and MoGe [2] we observed that a gap similar to the

superconducting gap persists inside the vortex core. We try to explain this phenomenon in terms of

rapid vibration of the vortices, due to Quantum fluctuations, about their centers and hence mixing the

normal metallic nature of the cores with the superconducting gap. We prove this conjecture by means

of fitting the experimental data with LDOS obtained by simulating this vibration on a vortex lattice

which is generated by solving Usadel equation in 2-dimension [3].

References:

1. Magnetic field induced emergent inhomogeneity in a superconducting film with weak and

homogeneous disorder: Rini Ganguly, Indranil Roy, Anurag Banerjee, Harkirat Singh, Amit Ghosal

and Pratap Raychaudhuri; Physical Review B 96 (2017), 054509.

2. Melting of the vortex lattice through intermediate hexatic fluid in a-MoGe thin film: Indranil Roy,

Surajit Dutta, Aditya N. Roy Choudhury, Somak Basistha, Ilaria Maccari, Soumyajit Mandal, John

Jesudasan, Vivas Bagwe, Claudio Castellani, Lara Benfatto, Pratap Raychaudhuri;

arXiv:1805.05193v2 (in Press in Physical Review Letters).

3. General solution of 2D and 3D superconducting quasiclassical systems: coalescing vortices and

nanoisland geometries: Morten Amundsen and Jacob Linder; Scientific Reports 6 (2016) 22765.


25th


27

Organic Flexible Nanogenerators for Mechanical Energy Harvesting Farsa Ram,

1,2 and Kadhiravan Shanmuganathan*

1,2

1Polymer Science and Engineering Division, CSIR-National Chemical Laboratory,

Dr. Homi bhabha Road, Pune, Maharashtra-411008, India 2

Academy of Scientific and Innovative Research, CSIR-National Chemical Laboratory,

Dr. Homi bhabha Road, Pune, Maharashtra-411008, India

*Corresponding author’s E-mail: [email protected]

Presenting author’s E-mail: [email protected]

Abstract:

Nanogenerators (NGs) harness the electricity from waste heat or mechanical motions. There

is a wide range of mechanical energy/motions e.g. wind flow, human walking, breathing,

vibrations from various surfaces, etc., which can be converted into electricity. The human

physiological motion with these self-powering NGs could be used for health monitoring.

Piezoelectric NGs (PENGs) are widely used in internet of things, security, environmental and

implantable medical devices where mechanical energy is converted into electrical energy.1

Among the polymers, the poly(vinylidene) fluoride (PVDF) shows highest ferro/piezoelectric

effect, which crystallize into the thermodynamically stable non-polar phase (α-phase) upon

melt processing. The piezoelectric properties come from electroactive phases (β and γ) of

PVDF.2 Herein; we report the use of fluorine modified cellulose as a β/γ phase initiator in the

PVDF. The fluorine modification on cellulose helps to reduce the phase separation, which

may occur in hydrophilic unmodified cellulose. The favorable hydrogen bonding between

PVDF and fluorinated cellulose led PVDF and its co-polymer to crystallize into the

electroactive phases. Further, we fabricated flexible devices for mechanical energy

harvesting.3 The FNC/PVDF NGs have four times higher output voltage upon applying the

periodic impact force and has 24 times higher sensitivity towards the tiny vibrations.

Figure: Vibrational sensitivity in terms of output voltage, PVDF (top) and 5wt% PVDF/FNC

(bottom).

References: 1. Wang, Z. L., Mater. Today 2017, 20, 74-82.

2. Lovinger, A. J., Science 1983, 220, 1115-1121.

3. Ram, F.; Ambone, T., Sharma, A.; Murugesan, R.; Kajale, D.; Borkar, V.; Ali, S. F.; Balu,

P. K.; Kumaraswamy, G.and Shanmuganathan, K. J. Phys. Chem. 2018, 122, 16540-16549.


25th


28

Mechanical vibration damping by thermal plasma synthesized iron oxide nanoparticles

Suyog A. Raut, S. Premkumar, Sudha V. Bhoraskar and Vikas L. Mathe

Abstract:

Currently vibration damping or shock absorbing technologies uses magnetorheological fluids

which consist of micron sized soft magnetic particles (mostly carbonyl iron). The use of

micron sized particles leads to more complicated issue, sedimentation. Here we use thermal

plasma synthesized iron oxide nanoparticles (size ranging from 10-100 nm), which shows

improved stability in carrier liquid. Thermal plasma synthesis process provides clean

synthesis route, controlled atmosphere etc. The iron oxide nanoparticles used here require no

surfactant to disperse them in liquid instead solid loading can be increased to stabilize them.

25th


29

Multi-frequency Radio Study of the Galaxy Cluster Abell 2744

Sameer Salunkhe and Surajit Paul

Department of Physics, S. P. Pune University,

Ganeshkhind, Pune 411007, India

presenting auther: [email protected]

Abstract:

Clusters of galaxies are the largest (_ Megaparsec scale) gravitationally bound structures in the

Universe. They are in general in thermal equilibrium and are prominent X-ray sources. But, some

of them are also detected at radio wavelength [? ] con_rming the presence of cos- mic ray electrons

and magnetic _elds in the Intra-Cluster Medium (ICM). Since radio synchrotron emission from

galaxy clusters are transient phenomena on cosmologi- cal timescales, it is de_nitely connected to

the dynamical states of the systems. And the radio study of the galaxy clusters also allows us to

understand the particle energy spectrum better. In this work, we have studied one such galaxy

cluster (Abell 2744) in multi-radio frequency to

understand its dynamical state and particle energy spectrum.

References:

[1] Ferreti L., Giovannini G.et. al., A&ARv, 20, 54

[2] Ebeling H., Edge A. C., et al. 2010, MNRAS, 407, 83

[3] Pearce C. J. J., van Weeren R., et al. 2017, ApJ, 845, 81

[4] Paul S., Salunkhe S., et. al., submitted to MNRAS

25th


30

Model for growth, transport and morphology of fungal hyphae

Bhagyashri Shinde1, Shagufta Khan

1 and Sudipto Muhuri

1

1Department of Physics, Savitribai Phule Pune University, Ganeshkhind, Pune

411007, Indian

Abstract:

Elongation and branching process of a fungal hyphae involves transport of membrane

bound vesicles by molecular motors from the sub-apical region to the tip of the hypha. At

the tip the intracellular organelle-Spitzenkrper facilitates utilization of the vesicles for the

purpose of synthesis of cell wall and resultant growth and branching of the hyphae. To

model the transport and development process, we propose a lattice gas model which is a

generalization of dynamically extending exclusion process (DEEP) which includes the

process of dynamical creation of branching sites at the tip and the associated process of

particle loss from the growing 1-d lattice. We derive an approximate analytic form of the

spatial profile of vesicle distribution on the growing hyphae, the temporal profile of the

length of the hyphae, and the velocity of the tip of the hypha and compare it with the

Monte-Carlo simulations and making some qualitative comparison with experiments.

Further we also simulate the 2-d morphology of the fungal hyphae resulting from the

branching process of the original hyphae, and characterize the effect of nutrient supply,

growth at the tip, and branching on the resultant 2-d morphology.

25th


31

Structural and Electrical Properties of 2D/2D MoS2-

hBN Mosaic Structure and Trieboelectric

Nanogenerator Application

Swati Parmar,[a]

Abhijit Biswas,[c]

Sachin Kumar,[c]

Bishakha

Ray,[d]

Suvarna Datar[d]

* satishchandra Ogale[c]

* and Suresh Gosavi[b]

*

aDepartment of Technology, Savitribai Phule Pune University,

Pune-411008, India

bDepartment of Physics, Savitribai Phule Pune University, Pune-

411008, India

cDepartment of Physics, Indian Institute of Science Education and

Research, Pune-411008, India dDefense Institute of Advanced

Technology, Pune, Maharashtra-411025, India

Abstract:

In view of their immensely interesting and intriguing properties, di erent 2D materials are being

intensely re-searched in search of novel e ects and diverse applica-tion interests; however studies on

integrating two such 2D materials into an application-worthy thin lm plat-form are rather few. Herein,

we have grown MoS2-hBN 2D-2D composite thin lms by the pulsed laser depo-sition (PLD)

technique, known for its ability of precise stoichiometry and growth control. Structural characteri-

zation by Raman, x-ray photoelectron spectroscopy and HRTEM con rms the concomitant presence of

both the phases (1T and 2H of MoS2) in the deposited lm. Tem-perature dependent resistivity study

reveals an interest-ing semiconductor-metal-semiconductor reentrant tran-sition as a consequence of

competing phases as well as phonon mode softening, as con rmed by the tempera-ture dependent

Raman spectroscopy. Furthermore, elec-trostatic force microscopy (EFM) was also performed at di

erent bias voltages. The phase contrast in the EFM images was noted to be much higher in the

MoS2/h-BN case as compared to the individual MoS2, h-BN sam-ples, and the bias voltage

dependence showed character-istic parabolic shape which when analyzed re ected work function

changes. A triboelectric nanogenerator (TENG) device containing multiphase MoS2-hBN thin lm as an

electron acceptor is seen to exhibit enhanced peak power density with respect to the pristine MoS2 thin

lms, re-ecting highly e cient capture of triboelectric electrons, consistent with work function changes

suggested by the analysis of EFM. This study brings out the potential of 2D-2D nanocomposite lms as

device functionality en-abling architectures.

25th


32

The electrical resistivity of the composite MoS2/h-BN lm was found to be 12 mOhm-cm at T = 300 K,

while that of MoS2 was 16 mOhm-cm as shown in g. 1b. The lower resistivity for the composite case

can be attributed to the enhanced 1T phase of MoS2. In the case of the composite, the T-dependent

resistivity showed an un-expected reentrant semiconductor-metal-insulator tran-sition near 250 K

which has a lattice connection as re-vealed by Raman spectroscopy. We have also designed a TENG

device as shown in Fig.1d, When this devicearchitecture was subjected to triboelectric measurement,

an average output voltage of 14 V and 6 V was obtained for MoS2-BN and pristine MoS2 cases,

respectively (Fig-ure 1d). Despite the physical properties, these composite

FIG. 1. Shows the MoS2-hBN 1T/2H Characterisation and their application. (a) Raman spectroscopy of MoS2-

hBN thin lm and their comparison with prestine cases, (b) R-T mea-surement and TEM analysis of 1T/2H MoS2

with hBN mosaic lm, (c) I-V characteristics and (d) Triboelectric nanogener-ator application.

systems have great application in self-powered exible smart devices as TENG by utilising the surface

charge potential between the layers. Nonetheless, above obser-vations might pave the way to engineer

the multiphase as well as the modulation of electronic properties in this rapidly progressing eld of 2D

materials, both from fun-damental science and application point of view.

25th


33

Visible-to-Ultraviolet Upconversion Sensitized Photocatalysis: Fact or

Fiction?

Sushant P. Sahua and Ezra L. Cates

b

aApplied Nanophotonics Laboratory, Louisiana State University, Baton Rouge, LA-70803,

bDepartment of Environmental Engineering, Clemson University, Clemson, SC-29634


Abstract:

Upconversion luminescence is a nonlinear optical process achieved by certain engineered materials,

which allows conversion of low energy photons into higher energy photons. Of particular relevance to

environmental technology, lanthanide-based upconversion phosphors have appeared in dozens of

publications as a tool for achieving visible light activation of wide-band gap semiconductor

photocatalysts, such as TiO2, for degradation of water contaminants. Supposedly, the phosphor

particles act to convert sub-band gap energy photons (e.g., solar visible light) into higher energy

ultraviolet photons, thus driving catalytic aqueous contaminant degradation. Herein, however, we

reexamined the photophysical properties of the popular visible-to-UV converters Y2SiO5:Pr3+

and

Y3Al5O12:Er3+

, and found that their efficiencies are not nearly high enough to induce catalytic

degradations under the reported excitation conditions. Furthermore, our experiments indicate that the

false narrative of visible-to-UV upconversion-sensitized photocatalysis likely arose due to

coincidental enhancements of dye degradation via direct electron injection that occur in the presence

of dielectric-semiconductor (phosphor-catalyst) interfaces. These effects were unrelated to

upconversion and only occurred for dye solutions illuminated within the chromophore absorption

bands. We conclude that upconversion using Pr3+

or Er3+

-activated systems is not a technologically

appealing mechanism for visible light photocatalysis and provide experimental guidelines for

avoiding future misinterpretation of these phenomena.

Figure: Cartoon Illustration of Mechanism of Visible-to-UV upconversion sensitized Photocatalysis

References:

1. Sahu, S. P.; Cates, S. L.; Kim, H. I.; Kim, J. H.; Cates, E. L., Environ. Sci. Technol. 52, 2018, 2973-

2980.

25th


34

Design and Development of Quartz Tuning Fork based Sensor Array for

Metabolic Rate monitoring

SusmitaRatha, Saurabh Parmar

a, and SuwarnaDatar

a

aDepartment of Applied Physics, Defence Institute of Advanced Technology, Girinagar, Pune, 411025


Abstract:

Breath analysis has attracted a lot of scientific interest as a potential non-invasive diagnostic

method [1]. Human breath has been used as a potential tool for the diagnosis and study of diseases.

Breath Volatile Organic Compounds (VOCs) are either generated in the body or may be absorbed

as contaminants from the environment. VOCs are added to breath as results of various metabolic

processes. Ketosis is a physiological state in which fat metabolism rate is increased due to the lack of

glucose as energy source and as fat is oxidized, ketones are produced. The concentration of Ketone

bodies in human systems can directly indicate the metabolism rate [2]. QTFs are single crystal quartz

mechanical oscillators which can be electrically excited, and their resonant frequency tracked with

great precision. In the present work the QTF is functionalized using Polymers by making the film on

the tines of the QTF. These modified QTFs respond to analyte in the form of change in the resonant

frequency which helps us in detecting the analyte. These QTF sensors were used to detect ketone

bodies (Acetone) which are produced by the oxidation of fatty acids (Metabolism) [3].

References:

1. Saasa, Valentine, et al. "Sensing technologies for detection of acetone in human breath for diabetes

diagnosis and monitoring." Diagnostics 8.1 (2018): 12.

2. Gouma, Pelagia-Irene, MaenAlkhader, and Milutin Stanacevic. "Metabolic rate monitoring and weight

reduction/management." Engineering in Medicine and Biology Society (EMBC), 2014 36th Annual

International Conference of the IEEE. IEEE, 2014.

3. Sampson, Abraham, et al. "Quartz tuning forkbased sensor for detection of volatile organic

compounds: towards breath analysis." Materials Research Express 5.4 (2018): 045407.

25th


35

Synthesis of Platinum Decorated RGO-TiO2 (P25) Composites for

Enhanced Photocatalytic Hydrogen Evolution and Dye Degradation

Yogesh Shinde, and Pragati Thakur*

Department of Chemistry, Savitribai Phule Pune University, Pune, Maharashtra 411 007. Presenting author: [email protected]

*Corresponding author: [email protected]

Abstract:

In modern civilization to meet the increasing demand of energy without polluting environment is the

biggest challenge. Hydrogen is considered as a clean fuel, as it burns without emission of harmful

gases. To minimize pollution and meet demand of energy it is essential to produce hydrogen from

water. Graphene, a single layer of graphite, possesses unique two dimensional structures, high

conductivity, electron mobility and high specific surface area. It has been used as an important

component for making composite materials with various semiconductors viz. TiO2, CdS, ZnO etc. due

to its excellent electron capture and storage capacity. In the present study we have synthesized

Platinum decorated graphene oxide-TiO2 composite using commercially available P25 TiO2 by simple

hydrothermal method for photocatalytic hydrogen evolution. Platinum (Pt) was deposited on RGO-

TiO2 composite by photodeposition method. Synthesized composites are characterized by various

methods like XRD, FTIR, Raman, SEM and TEM. These characterized composites were further

investigated for photocatalytic hydrogen evolution using methanol water mixture in UV light.

Percentage of RGO and Pt in the composite was optimized for enhancement of photocatalytic

hydrogen evolution. Stability and reusability of optimized photocatalyst was checked for hydrogen

evolution. Optimized photocatalyst was further used for photocatalytic degradation of dye under UV

light irradiation.

References:

1. Daniel C, Dmitry V, Jacob M, Alexander S, Zhengzong S, Alexander S, et al; ACS Nano, 4 (2010),

4806-4814.

2. Chen X and Mao S; Chem Rev, 107 ( 2007), 2891-2959.

3. Yan X, Kang T, and Yang Y; J Phys Chem B, 110 (2006), 25844-25849.

4. Perera S, Mariano R, Vu K, Nour N, Seitz O and Chabal Y; ACS Catal. 2 (2012), 949−956.

5. Shinde Y, Wadhai S, Ponkshe A and Thakur P; Int. Jour. Hydrogen Energy, 43 (2018), 4015-4027.

6. Li Q, Guo B, Yu J, Ran J, Zhang B, Yan H, et al; J Am Chem Soc, 133 (2011), 10878-10884.

7. Nainani R and Thakur P; Water Sci Tech, 73 (2016), 1927-1936.



25th


36

Light-cone and front dynamics of single particle extended quantum walk

Hemlata Bhandari, P. Durganandini

Department of Physics, Savitribai Phule Pune University, Ganeshkhind, Pune 411007, India

Abstract:

We study the light-cone and front dynamics of a single particle extended quantum walk with nearest

and next nearest neighbour hopping for an initially localized state. Speci_cally, we study the

dynamical global and local scaling structure of the cumulative probability distribution function using

analytical and numerical methods. The global scaling shows the existence of a 'causal light cone'

corresponding to excitations travelling with a velocity smaller than a maximal 'light velocity'.

Maximal fronts moving with _xed 'light velocity' bound the causal cone. The front regions spread

with time sub di_usively exhibiting a local Airy scaling which leads to an internal staircase structure.

At a certain critical next nearest neighbour hopping strength, there is a transition from a phase with

one 'causal cone' to a phase with two nested 'causal cones'. The corresponding cumulative distribution

proles showing two kinds of global and local scaling behaviour and the existence of an additional

internal staircase structure. The time evolution of a single particle quantum walk on the one

dimensional lattice with an initially localized state is shown to be equivalent to the time evolution of a

domain wall initial state in a corre sponding spin chain system. The study also provides a model

showing the emergence of nested causal cones with two 'light velocities' and the existence of more

than one kind of propagating quasi particle in nested integrable models.

[1] J. Kempe, Contemp. Phys. 44, 307 (2003).

[2] Y. Aharonov, L.Davidovich and N.Zagury, Phys. Rev. A 48, 1687 (1993).

[3] P. L. Krapivsky, J. M. Luck and K. Mallick, J. Phys. A Math. Theor. 48, 475301 (2015).

[4] S De Toro Arias and J M Luck, Journal of Physics A: Mathematical and General 31, 7699 (1998).

[5] Hunyadi, V and Racz, Zoltan and Sasvari, L,Physical review. E 69, 066103 (2004).

[6] Naja_, K. and Rajabpour, M. A. and Viti, J, Phys. Rev.

B 97, 205103 (2018). [7] S. Dadras, A. Gresch, C. Groiseau, S. Wimberger, and G.

S. Summy, Phys. Rev. Lett. 121, 070402 (2018).

[8] F. Zahringer, G. Kirchmair, R.Gerritsma, E.Solano, R.Blatt and C.F. Roos, Phys. Rev. Lett., 104,

100503 (2010).

[9] A. Peruzzo, M. Lobino, J.C.F. Matthews, N. Matsuda,N. Politi, K.Pulis, X.Q. Zhou, Y. Lahini, N.

Ismail, K.

Worho_, Y. Bromberg, Y. Silberberg, M.G. Thompson and J.L.OBrien, Science 329, 1500 (2010).

25th


37

Thermionic emission measurement of refractory materials using

indigenously developed thermionic emission measurement set up

Shalaka A. Kamble1, Srikumar Ghorui

2, Dhruva Bhattacharjee

3, Sudha Bhoraskar

1 and

Vikas Mathe1

1Department of Physics, Savitribai Phule Pune University,Ganeshkhind Pune 411007.

2Laser and Plasma Technology Division, Bhabha Atomic Research Center (BARC), Trombay,

Mumbai 400085, India

3ELECTRON Beam Facility, Khargar, Mumbai 410210, India


Abstract

Thermally induced emission of electrons is known as thermionic emission. Thermionic

emission is widely used in many devices such as electron microscopes, X-ray tubes,

accelerators, plasma thrusters etc.1–4 where refractory metals are used as emitters.

Measurement of thermionically emitted current is necessary for characterization. Efficiency

of thermionic emitter is defined based on it temperature of emission and the emitted electron

density. It is therefore necessary to carry out these measurements. In the present work,

thermionic emission measurement set up working at laboratory scale has been indigenously

developed. This method gives thermionic emission current density as well as measures work

function of emitter.

REFERENCES:

(1) Mogren, S.; Reifenberger, R. Surface Science 1987, 186 (1-2), 232–246.

(2) Zhou, S.; Zhang, J.; Liu, D.; Lin, Z.; Huang, Q.; Bao, L.; Ma, R.; Wei, Y. Acta Materialia

2010, 58, 4978–4985.

(3) Trenary, M. Science and technology of advanced materials 2012, 13 (doi:10.1088/1468-

6996/13/2/023002). (4) Cooper, C. M.; Gekelman, W.; Pribyl, P.; Lucky, Z. Review of

Scientific Instruments 2010, 81 (8).


25th


38

Ferroelectric, Dielectric and Piezoelectric Properties of Hf Modified

BaTiO3 O. A. Ramdasi

1, T.C.Darvade

1, P.S.Kadhane

1, B.G.Baraskar

1,

Y. D. Kolekar1, R. C. Kambale

1*

1*Smart Materials Research Laboratory, Department of Physics,

Savitribai Phule Pune University, Pune, Maharashtra (India), 411 007


Abstract: Hafnium (Hf) substituted BaTiO3 i.e. (BaTi1-xHfx)O3, with x = 0, 0.04, 0.08 (abbreviated as BT, BHT-1

and BHT-2); electroceramics were prepared by solid state reaction method and studied their

ferroelectric, dielectric and piezoelectric properties. X-ray diffraction study reveals the formation of

tetragonal symmetry with space group P4mm. The SEM images show the granular dense microstructure

with decrease in grain size. The BHT-1 ceramic exhibits improved ferroelectric, dielectric and

piezoelectric properties due to its uniform grain size and highly dense structure, compared to other

ceramics. P-E hysteresis loop measurements confirm the ferroelectric nature of all the samples with

moderately high remanent polarization (Pr 8.84 µC/cm2) and lower coercive field (Ec 2.80 kV/cm)

for BHT-1. The BHT-1 shows higher value of dielectric constant and lower dielectric loss that indicate

its importance for practical applications viz. capacitors, memory storage applications, etc. The higher

value of piezoelectric coefficient (d33 238 pC/N) observed for BHT-1 signifies that Hf substituted

BaTiO3 ceramic system may be promising candidate for environmental friendly energy harvesting

applications. All the improved properties are correlated with the density and microstructure

measurements.

Figure: X-ray diffraction patterns for the BaTi1-xHfXO3 (where x = 0, 0.04, 0.08) (abbreviated as BT,

BHT-1 and BHT-2) respectively.

References:

1. S.Anwar, P.R.Sagdeo, N.P.Lalla, J.Phys.Condens.Matter, 18, 3455-3468, (2005).

2. P. S. Dobal, S. Bhaskar and R. S. Katiyar, J. Appl. Phys. 86, 828-834 (1999).

3. W. Liu and X. Ren, Phys. Rev. Lett., 103, 257602 (2009).


25th


39

Synthesis of Highly Efficient Metal Free Phosphorus doped Graphitic

Carbon Nitride / P25 (TiO2) Composite for Visible Light Photocatalytic

Hydrogen Evolution

Sachin Wadhai and Pragati Thakur*

Department of Chemistry, Savitribai Phule Pune University, Pune - 411007 Presenting author: [email protected]

Corresponding author: [email protected]

Abstract:

The development of heterojunction photocatalyst for efficient solar energy conversion is essential for

practical application. In this study, simple and low cost method has been implemented to improve the

visible light photocatalytic activity. The graphitic carbon nitride (CN), Phosphorus doped graphitic

carbon nitride (PCN) and its composites were successfully characterized by XRD, DRS, FTIR, SEM

and UV-visible spectroscopy. The doping of phosphorus in gC3N4 changes its optical and textural

properties. DRS study clearly depicts increased absorption of visible light in case of PCN as

compared to CN. PCN (65 μmol/g) shows 1.5 times increase in hydrogen evolution capacity as

compared to CN (41 μmol/g). CN and PCN coupling with P25(TiO2) shows dramatic enhancement in

photocatalytic hydrogen evolution activity as compared to bare P25(TiO2). CN-P25 (TiO2) show

twenty-two fold (920 μmol/g) and PCN- P25 (TiO2) shows nearly forty fold (2531 μmol/g) increment

in hydrogen production as compared to bare P25(TiO2). The overwhelming enhancement in

photocatalytic yield can be attributed to the charge transfer from CN or PCN to P25(TiO2) thereby

reducing the probability of electron-hole recombination. Simple phosphorous doping to CN and then

coupling PCN with P25 (TiO2) has given rise to notable low-cost metal free photocatalyst opening

great avenues in the field of energy and environment.

References:

1. Zaiwang Zhao, Yanjuan Sun and Fan Dong*; Nanoscale, 7, (2015), 15.

2. Xin Tan, Hassan Tahini, and Sean Smith*, ACS Catal. 6, (2016), 7071.

3. Sajid Ansari, Mohammad Ansari & Moo Cho1, Scientific Reports, 6, (2016), 27713.

4. Bing Liu, Liqun Ye, Ran Wang, Jingfeng Yang, Yuexing Zhang, Rong Guan, Lihong

Tian* and Xiaobo Chen*, ACS Appl. Mater. Interfaces, 10, (2018), 4001.



25th


40

Development of Nuclear battery using Tritium gas filled tubes and

Photovoltaic devices

Ambadas B. Phatangare, Sanjay D. Dhole, Shailendra S. Dahiwale and Vasant N. Bhoraskar

Microtron Accelerator Laboratory, Department of Physics, Savitribai Phule Pune University, Pune-

411007, India


Abstract:

Gaseous tritium light source is made from the combination of radioactive isotope hydrogen (1H3) gas

and phosphorus (ZnS:Cu) to generate visible light. Tritium radioactive isotope of hydrogen emits

electrons through beta decay and when these electrons interact with the phosphor coated inside a glass

tube, green fluorescent light is produced. We have developed photovoltaic type nuclear battery using

4 a-Si solar cells (each having 67 mm×33 mm) and 9 tritium radioactive gas filled glass tubes each of

1.5 Ci activity. A sandwich-type a-Si/H-3 light tubes/a-Si structure was assembled through cylindrical

tritium light tubes to investigate photon radiation effects. Under the total photons interacting of the

nine Tritium gas filled radioactive tubes, the structure presents open-circuit voltage of 5.44 V and

short-circuits current of 1 µA. The a-Si and tritium light tubes exhibits a great potential for

developing photovoltaic type batteries with low power of 5.44 micro-watts for the charging

application electric power source is not available, such as under sea, on mountain, military

applications,…etc.

Figure 1: An experimental setup showing fabrication of photovoltaic nuclear battery using tritium radioactive

gas filled light tubes and amorphous silicon.

References: (i) B. H. Kim & J. W. Kwon, Scientific Reports, 4, 5249.

(ii) M.G. Li and J. Zhang, 2015 28th

IEEE International Conference on Micro Electro Mechanical

Systems (MEMS). DOI: 10.1109/MEMSYS.2015.7051156.

e-

e-

e-

e-

e-

h

h

h

h

h

Tritium

(H-3 gas)

GlassPhosphor

h

h

h

h

h

hh

h

h

h

h

h

hh

V

Tritium light

Tubes

a-Si solar cell

a-Si solar cell

VOC= 5.4 V, Isc= 1µA

Tritium radioactive gas filled tube Assembly of Photovoltaic Nuclear Battery


25th


41

Sustained multiferroicity in liquid crystal induced by core/shell geometry

of quantum dots

Swapnil Doke,1,#

Prasun Ganguly,2,* and Shailaja Mahamuni

1,*

1Department of Physics, S. P. Pune University, Pune 411 007, India

2Department of Physics, Faculty of Sciences, National Defence Academy, Khadakwasla,

Pune 411 023, India

# Presenting Author: [email protected]

* Author for Correspondence: [email protected],

[email protected]

Abstract:

Co-ZnO/ZnO core/shell (CZZ) quantum dots (QDs) dispersed in ferroelectric liquid crystal

(FLC) reveal improved spontaneous polarization in addition to ferromagnetic ordering. A

suitable concentration of diluted magnetic semiconductor core/shell QDs was added into pure

FLC (KCFLC 7S) material to study its ferroelectric and ferromagnetic properties. Increased

cobalt concentration in the core of CZZ QDs enhances the magnitude of saturation

magnetization. The inherent magnetic field of core/shell QDs coupled with the director field of

the FLC molecules without interfering intrinsic properties of host FLC and dopant QDs.

Remarkably, optimized concentration of QDs does not disturb intrinsic ferroelectric nature of

the host as confirmed by ferroelectric and helical pitch measurements. This work should be

helpful for future liquid crystal display systems based on QDs, which exhibit both electric and

magnetic memory within itself.

Figures

-10 -5 0 5 10

-30

-20

-10

0

10

20

30

0 2 4 6 8 1018

20

22

24

26

28

Ps (

nC

/cm

2)

Conc. of Co in core (%)

Ps

Pure FLC

Po

lari

zati

on

(n

C/c

m2)

Electric Field (kV/cm)

Pure FLC

CZZ-0/FLC

CZZ-2/FLC

CZZ-5/FLC

CZZ-10/FLC

Fig. 1. P-E hysteresis loop

-4000 -2000 0 2000 4000

-1.0

-0.5

0.0

0.5

1.0

-20 -10 0 10 20-0.010

-0.005

0.000

0.005

0.010

Mag

neti

zati

on

, M

(m

em

u/g

)

Applied Magnetic Field, H (Oe)

Pure FLC

CZZ-0/FLC

CZZ-2/FLC

CZZ-5/FLC

CZZ-10/FLC

Fig. 2. M-H hysteresis loop

References

[1] F. Brochard and P.G. de Gennes, J. Phys.31, 691 (1970).

[2] T. Joshi, A. Kumar, J. Prakash, and A.M. Biradar, Appl. Phys. Lett.96, 253109 (2010).

[3] B. Rožič, M. Jagodič, S. Gyergyek, M. Drofenik, S. Kralj, Z. Jagličić, and Z. Kutnjak,

Ferroelectrics431, 150 (2012).

[4] P. Ganguly, A. Kumar, K. Muralidhar, and A.M. Biradar, Appl. Phys. Lett.108, 182905 (2016).

[5] S. Doke, K. Sonawane, V. Reddy, P. Ganguly, and S. Mahamuni, Liq. Cryst.45, 1518 (2018).


25th


42

Dosimetric properties of BaF2:X (X= Gd, Yb and Ce) phosphor for -ray

Kishor H. Gavhane, M. S. Bhadane, V. N. Bhoraskar, S. D. Dhole, and S. S. Dahiwale

Microtron Accelerator Laboratory, Department of Physics, Savitribai Phule Pune University, Pune

411007, India


Abstract:

Now a day’s, lots of research work have been carried out for the development of new dosimetric

materials for detectors, radiation therapy, and medical applications. Thermoluminescence is a method

which used for dose measurements of different ionizing radiations. BaF2 is a well-known phosphor

used for luminescence and photonic applications, due to their superior chemical and thermal

properties. The Zeff of BaF2 is ~ 51; therefore it can be used in high dose measurement systems.

Looking at the suitable properties of BaF2 for dosimeters, we used this material in the present study.

We used different dopant (i.e. Gd, Yb and Ce) to study dosimetric properties of BaF2 phosphor. Cubic

phase of BaF2 synthesized by simple Co-precipitation method and annealed at 300 °C to 700 °C to

optimized dosimetric peak. TL observations show good linear response from 1 Gy to 10 kGy and

negligible fading. The results of trapping parameters, order of kinetics, frequency factor, and optimum

fitting (1.7 %) were calculated through GCD system. Finally, the possible occurrence of a

luminescence phenomenon was discussed briefly for dosimetric applications.

(A) BaF2:Yb (B) BaF2:Gd

Figure: Glow Curve Optimization of BaF2 phosphor irradiated at a dose of 1 kGy gamma rays

Refferences:

1. J. J. Bos, Theory of Thermoluminescence, Rad. Meas. 41 S45-S56(2007)

2. B.C. Bhatt, M.S. Kulkarni, Intern. J. Lumin. Appl. 3, 6 (2013)

3. G. Kitis, J. M. Gomez-Ros, J. W. N. Tuyn, J. Phys. D: Appl. Phys. 31 2636-2641(1998)

4. Numan Salah, P. D. Sahare, Radiation Effects, Vol. 159, pp. 321–334 (2004)

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43

Proliferation of Human Mesenchymal Stem cells on UHMWPE polymer

surface as an effect of plasma processing.

Supriya E. More, Geetanjali B. Tomar, Jay Dev, Prajakta Makar, S. V. Bhoraskar, V. L.

Mathe

Abstract:

The work summarized the study related to the surface modification of UHMWPE by low

pressure plasma for bone tissue engineering. Microwave assisted electron cyclotron

resonance (ECR) plasma was used to generate C-N and C-O related functional groups to be

grafted on the surface along with improving its surface energy for the determination of

proliferation and adhesion of human gingival mesenchymal stem cells (GMSCs). From the

MTT assay (carried out for 24, 48 and 72 h) the rate of proliferation of MSCs was observed

to be higher by 1.6 times for the oxygen terminated surface as compared to nitrogen

terminated functional groups, whereas the cells cultured on untreated surfaces had the lowest

rate of proliferation. Immunofluorescence measurements were further use to visualize the

growth of GMSCs (osteoblast precursors) and PBMNCs (osteoclast precursors) on the

plasma treated surfaces. It was noticed that osteoblast precursor cells grow faster (on 1 min

treatment) as compared to osteoclast. However for prolong plasma treatment (2 min) the cell

density of osteoclast outnumber the growth of osteoblast. Results that indicates the total

plasma fluence is a controlling parameter for obtaining desired ration of osteoblast and

osteoclast. The surface energy was estimated by measuring contact angle measurement and a

maximum surface energy was obtained to be 140 mJ/m2 for HN/O2 plasma treated wherein it

was 69 mJ/m2 for pristine sample. The roughness parameter estimated by atomic force

microscopy was increased from 6 nm for pristine to a value of 17 nm for O2 treated polymer.

Fourier Transform Infrared (FTIR) spectroscopic analysis showed the grafting of N-H/C-N

related groups by HN plasma and C-O/C=O related groups by O2 plasma. The extent of

grafting was assisted by X-ray photoelectron spectroscopy.

25th


44

Development of Antibiotic-Magnetic Carbon Nanovectors Complexes for

Enhancing Efficacy of the Antibiotic

Prachi Ghoderaoa, Anjali A. Kulkarni

b, and Tejashree Bhave

a

aDepartment of Applied Physics, Defence Institute of Advanced Technology, Pune,411025, India..

bDepartment of Botany, Savitribai Phule Pune University, Pune, 411007, India.

*Presenting Author: [email protected]

Abstract

Carbon nanotubes are being extensively explored as drug delivery carriers for intracellular drugs’

transport [1]. Herein we communicate Iron oxide (Fe3O4) nanoparticles (NPs) embellished

multiwalled carbon nanotubes (MWCNTs) as a nanovector for efficacious delivery of Doxycycline

(Doxy) which is a broad-spectrum antibiotic. However, limited drug bioavailability with unacceptable

efficacy and safety profiles are the prime drawbacks of Doxy [2]. To combat these pitfalls, we have

embellished the nanovectors with Fe3O4 NPs followed by loading Doxy onto it. First, we have surface

tailored multiwalled carbon nanotubes (MWCNTs) with strong acids and then these were embellished

with Iron oxide (Fe3O4) nanoparticles (NPs). Further, Doxy was loaded onto MWCNTs/Fe3O4

nanovectors (NVs) in an incubator shaker for 6 h at 37°C.

To study successful embellishment of Fe3O4 NPs on MWCNTs, we have carried out Raman

Spectroscopy and High Resolution Transmission Electron Microscope studies. In the antibacterial

activity studies, it was observed that the conjugates inhibit growth of the Gram-positive bacterium

Staphylococcus Aurius with exhibition of magnet-enticed increased cellular uptake. This substantially

ameliorates the efficacy of Doxy, even at a lower concentration of drug loading.

In detail Raman studies, it was observed, the emergence of prominent RBM at higher 300 cm-1

, with

it’s sharpening has been observed after Fe3O4 NPs embellishment on MWCNTs. Moreover, it shows

the presence of Fe3O4 symmetry state that have been overlapped with RBM at 300 cm-1 [3].

Systematic D peak red shift of D peak by 20 cm-1

and sharpening of G peak split is indicative of

overall enhancement in reactivity of MWCNTs after functionalizing hem with Fe3O4 NPs (Figure 1).

Antibacterial assessment against S. Aureus reflects, 32 % of Doxy loaded on MWCNTs/Fe3O4 in

conjugates have exhibited predominant zone of inhibition in comparison to that of 100% of native

Doxy (Figure 2) even at the lower concentration of the drug. This increased efficacy is statistically

significant both at 95% and 99% level of confidence as per the ANOVA conducted. The increased

efficacy may be attributed to distinct binding sites of cell membrane with cationic receptors which

may facilitate interaction of Doxy-MWCNTs/Fe3O4 conjugates through "adsorptive endocytosis"

pathway [4].

[email protected]

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45

Figure 1 Illustrates display of Prominent shift in RBM. D Shift and inset shows split in D peak. (c)

Details of G shift and inset reflects splits in G band of MWCNTs/Fe3O4 NVs.

Figure 2. Actual photograph of antibacterial assay carried on Gram-positive bacterium, S.Aurius (a)

Neat Doxy and (b) Doxy-MWCNTs/Fe3O4

In conclusion, Doxy-MWCNTs/Fe3O4 conjugates were prepared and studied for their potency as an

encouraging treatment approach. Embellishment of Fe3O4 NPs on MWCNTs followed by loading of

Doxy onto this composite has created a promising nanovector.

References:

1] Bianco, A.; Kostarelos, K.; Prato, M. Expert Opin. Drug Deliv. 5 (2008) 331–342

2] Gencosmanoglu, R.; Kurtkaya-Yapicier, O.; Tiftikci, A.; Avsar, E.; Tozun, N.; Oran, E. Sen. J.

Clin. Gastroenterol., 38 (2004) 484–489.

3] Jang, J.; Yoon, H. Adv. Mater. 15 (2003) 2088–2091.

4] Kalambur, V. S.; Longmire, E. K.; Bischof, J. C. Langmuir 23 (2007)12329–12336.

25th


46

Designing white light emitting phosphors using 2D hybrid perovskites Shrreya Krishnamurthya, Suresh Gosavi

a, Kiran Adhi

a and Satish Ogale b

aDepartment of Physics, Savitribai Phule Pune University, Pune 411 007.

Presenting author: [email protected] bDepartment of Physics, Indian Institute of Science Education and Research (IISER) Pune,

Pune 411007

Abstract:

Development of energy efficient devices such as non-linear optical switches, light emittingdiodes,

resistive switches, and lasing systems has attracted significant attention in recent years dueto the ever-

growing demand for such device systems by multiple application sectors. Amongst thevarious classes

of materials being explored in this context, the organic-inorganic hybrid perovskites(OIHPs) represent

a rapidly growing class ofmaterials with exceptional, intriguing, and highly tunabledevice-worthy

properties, especially for solar cells and other optoelectronic devices. In addition tothe basic 3D

versions of the hybrid perovskites, their low dimensional counterparts have also showninteresting

optoelectronic properties and promise for robust device applications. Two dimensional (2D) hybrid

perovskites are stoichiometric compounds having a periodic arrangement of alternatinginorganic

metal-halide sheets and organic molecules as cationic layers, also referred to as Ruddleson Popper

phases. They are “natural quantum well” structures which can be tailored easily to achievenovel

performing materials.We have synthesized and studied a specific family of disulfide bridge based 2D

organic inorganic hybrid perovskites using the cation, cystamine [2,2- dithiobis(ethylammonium),

abbreviated as SS] in the three lead halide (X = I, Br, and Cl) based systems, and explored their unique

photo-physical properties. Green, blue, and white emissions are noted in I, Br, and Cl based systems,

respectively. The role of the halide ion (X) in the [Pb-X4] cages on the luminescence of the disulfide

bridge based hybrid system is elucidated, and the correspondingsystematics are analyzed.

References: 1. E. R. Dohner, A. Jaffe, L. R. Bradshaw, H. I.Karunadasa, J. Am. Chem. Soc. 2014, 136 (38), 13154–13157

2. L.Mao, Y.Wu, C.C.Stoumpos, M.R.Wasielewski, M.G.Kanatzidis, J. Am. Chem. Soc. 2017, 139 (14), 5210–

5215

3. S.Krishnamurthy, P.Kour, A.Katare, S.Gosavi, S.Chakarvarthy and S.Ogale, APL Mat. , 2018, 6, 114204.

Spin coated Ag nanoparticles as a SERS substrate for trace detection of

food adulterant melamine in the milk powder.

25th


47

Imran M. Shaikh and S. D. Sartale*

Thin Films and Nanomaterials laboratory, Department of Physics, Savitribai Phule Pune University,

Pune-411007, INDIA


ABSTRACT

Ag nanoparticles having different size and coverage were grown by inexpensive and feasible

spin coating and chemical reduction method. Spin coating parameters were tuned to attain the various

size and coverage of Ag nanoparticles. The present study emphasizes on the optimization of spin

coating parameters mainly rpm so as to get large SERS enhancement. The Ag nanoparticles grown at

1000 rpm by spin coating and chemical reduction method shows good enhancement factor (107) with

good sensitive and reproducibility of the SERS signal. The optimized SERS substrate was

successfully employ to detect food adulterant melamine having different concentrations in the milk

powder.


25th


48

Synthesis of Ni nanoparticles by thermal plasma method and their

implementation for hydrogen production from alkaline sodium

borohydride solution

N.P. Ghodkea, S. Rayaprol

b, S.V. Bhoraskar

a, V.L. Mathe

a

aDepartment of Physics, Savitribai Phule Pune University, Pune-411007

bUGC-DAE Consortium for Scientific Research, Mumbai Centre, BARC – Trombay, Mumbai -

400085, India

Abstract:

Sodium borohydride has potential to be opted as fuel source due to its high gravimetric hydrogen

storage capacity (10.8 wt%) [1]. The reaction of NaBH4 with water occurs as

NaBH4 +2H2O NaBO2+4H2+Q

Usually in order to increase the rate of reaction catalyst is used. Non-noble metal catalyst such as

nickel (Ni) and cobalt (Co) as well as their alloys with borides acts as efficient catalyst [2]. Synthesis

method of catalyst plays an important role in modifying the surface structure. Also analysis of

reaction kinetics is important if designing of reactor has to be considered.

Here, we report synthesis of Ni nanoparticles by thermal plasma method and its application as catalyst

for hydrolysis of alkaline sodium borohydride solution. The catalytic activity of Ni nanoparticles was

tested for different concentrations of NaBH4, pH values of solution and temperatures. The reaction

kinetics with respect to NaBH4 concentration was analyzed in the temperature range of 300 -320 K. It

was found that kinetics of reaction was first order with respect to NaBH4 concentration in the

temperature range of 300 – 315 K while at 320 K the kinetics shifted to higher order. Thus, rate

limiting step here is adsorption of BH4- ions on surface of catalyst. It is expected that homogenous

catalyst show zero order kinetic reaction with respect to reactants [3]. However, surface reactivity of

the catalyst, which is prominently decided by the synthesis methodology and parameters, modify the

reaction kinetics. The maximum rate of hydrogen production was found to be 1240

ml/min/gm(catalyst) recorded at 320 K. The Activation energy was found to be 69.76 kJ/mol. The

post characterization of catalyst carried out using FTIR and SEM indicates formation of B-O layer on

surface of catalyst. The catalyst show quite stable and reproducible performance up to 5 cycles at 300

K.

25th


49

Figure 1: Hydrogen volume evolved at different temperature for 9pH 0.661 M NaBH4 solutions using

0.02gm of Ni nanoparticles

References:

[1] U. B. Demirci, “The hydrogen cycle with the hydrolysis of sodium borohydride: A statistical

approach for highlighting the scientific/technical issues to prioritize in the field,” Int. J. Hydrogen

Energy, vol. 40, pp. 2673–2691, 2015.

25th


50

Statistical model analysis of neutron induced reactions on 232

Th from

reaction threshold to 20 MeV for ADSS application.

T.S.Ganesapandy1,2

, S.D.Dhole1, J.J.Jeremiah

2,V.N.Bhoraskar

1

1Microtron Accelerator Laboratory, Department of Physics, Savitribai Phule Pune University,

Pune-411007. 2Department of Physics, Madras Christian College, Chennai-600059.


Abstract :

Excitation functions for (n,γ) and (n,2n) reactions from reaction threshold to 20 MeV on stable

Thorium isotope 232Th were calculated using TALYS-1.9 nuclear code. Hauser-Feshbach

calculations for the above reactions were carried out by invoking suitable options for level densities,

optical model potentials, pre-equilibrium effects and γ-ray strength functions. The effects of nuclear

model calculations on the excitation functions were studied keeping ENDF evaluation as a reference.

In earlier studies theoretical plots for (n,γ) and (n,2n) reaction cross-section to match experimental

data available in the EXFOR were obtained using EMPIRE and TALYS codes with default

parameters however couldn’t match with the corresponding experimental cross-section reported in

EXFOR library at all incident neutron energies. For each reaction a combination of input parameters

for TALYS 1.9 was identified that best reproduces the experimental data. The results of the present

study reveal that the TALYS 1.9 theoretical evaluation of the cross sections favours a higher pre-

equilibrium rate for a harder spectrum and this matches fairly well with the experimental as well as

with the evaluated data files and is important for the validation of nuclear model approaches with

increased predictive power of (n,xn) reactions for application of Thorium-based fuel in Accelerator-

Driven Sub-critical System.

Figure. 1: Excitation functions of (n,2n) and (n,γ) reactions of

232Th

References:

1. Koning, A.J.,Hilaire, S., Duijvestijn, M. 2008. NRG-1755.

2. Koning, A.J. et al., 2007. Nuclear Science and Engineering,156:3, 357-390.

3. Kumar, V., 2007. Pramana. J. Phys. 68, 315-324.

25th


51

Poster

Presentation

25th


52

CdS thin films grown by electrodeposition techniques as a buffer layer for

solar cell application.

Aparna Ukarande a, N.B.Chaure

a, and S.Chaure

b

a Electrochemical Laboratory, Department of Physics, Savitribai Phule Pune University, 411007,

b Department of Physics, College of Engineering, Pune, 411005,


Abstract:

Cadmium sulphide (CdS) is a metal chalcogenide semiconductor with a wide band gap of 2.42 eV at

room temperature (300K) [1]. This material has been widely used in many applications such as

optoelectronic devices, semiconductor lasers, sensors and solar cells. Several techniques have been

used to deposit the CdS thin films. In this work we have used electrodeposition technique to grow the

CdS layers using two electrode systems. The samples were grown at room temperature onto FTO

coated glass substrates. CdSO4 and Na2SO3 were used as Cd and S precursor. The deposition potential

was optimized using cyclic voltammetry technique [1]. The samples were annealed at temperature

420˚C for 20 minutes in muffle furnace. The samples were characterized to study the various

properties. The band gap of the sample was measured 2.4 eV using the UV-VIS Spectroscopy. XRD

data confirm the growth of hexagonal crystal structure of CdS. Nearly stoichiometric thin film were

grown at deposition potential -1.2V with respect to Ag/AgCl reference electrode. The samples were

compact, uniform and void free observed from SEM analysis [2].

Figure: Cyclic

Voltamogram recorded for CdS films.

References:

1. N.A. Abdul-Manaf, A.R. Weerasinghe, O.K. Echendu and I.M. Dharmadasa (2015). Electro-plating

and characterisation of cadmium sulphide thin films using ammonium thiosulphate as the sulphur

source. Journal of Materials Science: Materials in Electronics, 26 (4), 2418-2429.

2. Divya Boosagulla, Sreekanth Mandati, Ramachandraiah Allikayala and Bulusu V. Sarada, ECS J. Solid

State Sci. Technol. 2018 volume 7, issue 8, P440-P446.

http://jss.ecsdl.org/search?author1=Divya+Boosagulla&sortspec=date&submit=Submit

http://jss.ecsdl.org/search?author1=Sreekanth+Mandati&sortspec=date&submit=Submit

http://jss.ecsdl.org/search?author1=Ramachandraiah+Allikayala&sortspec=date&submit=Submit

http://jss.ecsdl.org/search?author1=Bulusu+V.+Sarada&sortspec=date&submit=Submit

25th


53

Coffee-ring Effect assisted, Surface modification Free Paper-based

Colorimetric Glucose Sensor

Prerna Unadkat1, Anurag Kanase

2, Sandip Wadhai

3, Arun G. Banpurkar

3

1Department of Physics, Fergusson College, Pune-India

2Department of Biomedical Engineering, Wayne State University, USA

3Department of Physics, Savitribai Phule Pune University, Pune-India


Abstract:

Paper-based analytical tools are commonly used to estimate various quantities like pH, blood sugar,

blood group and extensively used to diagnose various pathogens [1-3]. Mainly the paper-based device

is loaded with reagents to produce colorimetric response. The colorimetric readout/output generated

by the reagents on this paper provides an accurate readout of the concentration of the

analyte/pathogens. However, the reagent loading has to undergo chemical binding with the substrate

by using crosslinking polymerization method. If the reagents are free dried or drop casted without

using crosslinkers, they diffuse along with the diluent used creating a coffee-ring pattern. Here, we

present an alternative approach to utilize the coffee-ring generated color-gradient by iterating the

geometry of the paper-based substrate. This geometry generates a sharp band necessary for accurate

color intensity readout. We validate the geometry dependent readout in a glucose sensor made using

glucose oxidase, horse radish peroxidase, trehalose/gelatin and potassium iodide/starch. We process

the readout with computer vision for better accuracy. The data is then calibrated in a glucose sensor.

The use of different indicators allows us to study the difference in color intensity suitable in a visual

as well as digital readout. This reading loading approach is suitable to develop low cost colorimetric

sensors at low resource labs. We also identify the benefits and limitation of the geometries and their

mode of application.

Figure:Plot shows colur intensity against glucose concentration.

References:

1. Martinez, A. W., Phillips, S. T., Carrilho, E., Thomas III, S. W., Sindi, H., & Whitesides, G. M. (2008).

Simple telemedicine for developing regions: camera phones and paper-based microfluidic devices for

real-time, off-site diagnosis. Analytical chemistry, 80(10), 3699-3707. 2. Xia, Y., Si, J., & Li, Z. (2016). Fabrication techniques for microfluidic paper-based analytical devices

and their applications for biological testing: A review. Biosensors and Bioelectronics, 77, 774-789. 3. Zhang, D., Gao, B., Chen, Y., & Liu, H. (2018). Converting colour to length based on the coffee-ring

effect for quantitative immunoassays using a ruler as readout. Lab on a Chip, 18(2), 271-275.

25th


54

ArVirInd – A database of Arbo-Viruses from India

Sujay K Kirdavkara, D Hargude

a and Pratip Shil

a*

ICMR - National Institute of Virology,

130/1Sus Road, Pashan, Pune 411021. INDIA

*Corresponding Author: [email protected]


Abstract:

Climate change has resulted in enhanced propagation of Arthropod-borne viruses

(arboviruses like, Dengue Chikungunya, West Nile, Japanese encephalitis, Zika, etc) worldwide [1].

The densely populated Indian subcontinent is particularly vulnerable with a huge disease burden.

Controlling disease necessitates analyses of genome and proteome information for tracing viral

evolution and phylogenetics, identification of effects of mutations in newly emerging strains using

Bioinformatics tools [2,3]. Development or modification of vaccine components are also required.

Though existing bioinformatics databases like NCBI, etc store genome and proteome information

about viruses, but none of the existing databases enlist strains by "country of origin" and "date of

collection". This makes data retrieval from databases cumbersome. Also, none of these databases

provide any information about antigenicity, or epitope information on the antigenic proteins for the

viruses. Hence, development of database dedicated for arbo-viruses (both prevalent and emerging) in

India and the sub-continent is the need of the hour.

To overcome these difficulties we designed and developed a Bioinformatics database

(knowledge-base) that stores information on Arbovirus strains collected from the Indian subcontinent.

Curated and processed data for each protein/gene is available. Users can search the database by by

"country", and/or "year of origin". This unique database will be available from the website:

www.niv.co.in from March 2019. The screenshots of the user-interfaces are given in Figure 1.

Figure 1: Screenshot of the ArVirInd knowledgebase developed. Demo-version operational in

the Bioinformatics Lab, Pashan Campus.

References. 1. P Shil, et al. VirDisease 2018. 29 (1), 46-53.

2. D Pavitrakar, P Shil, et al. Arch. Virol. 2018;163(12):3215.

3. Singh R, P Shil, et al. Virus Res. 2011;158:179-87.

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55

Synthesis of γ-Fe2O3/rGO nanocomposite and its application as

Supercapacitor

Aditi Awatea, Sanjay Apte

b, Sunita Bhagwat

a and Bharat Kale

b

aDepartment of Physics, Abasaheb Garware College, Pune - 411 004

bCentre for Materials for Electronics Technology, Pune.



Abstract:

Supercapacitor devices are emerging as one of the promising energy devices for the future energy

technology. From the literature work we know that the transition metal oxides are suitable electrode

materials for pseudo-capacitors due to different oxidation states and different ions. There are many

metal oxides such as aluminum oxide, zinc oxide, tin oxide etc. Iron oxide (γ-Fe2O3) is the promising

active material in supercapacitors. Correlating with other metal oxides γ-Fe2O3 has relatively high

conductivity but low specific capacitance. Reduced graphene oxide plays a vital role in

supercapacitors as it helps to enhance the capacitance of the devices. In the present work we have

prepared nanocomposite electrode material composed of iron oxide (γ-Fe2O3) and reduced graphene

oxide. We report here with the synthesis of γ-Fe2O3/rGO nano-composites by co-precipitation method

using different concentrations of rGO. The nanocomposite material was characterized using X-ray

diffraction and Raman spectroscopy. The average crystallite size calculated by Debye Scherrer

formula is 3.46 nm. The electrochemical study of the as-synthesized composite material was explored

using cyclic voltammetry and galvanostatic charge/discharge tests. γ-Fe2O3/rGO nano-composites

showed different specific capacitance at 0.5 Ag-1

, 1 Ag-1

, 2 Ag-1

, 3 Ag-1

and 4 Ag-1

. Specific

capacitance varies as per concentration of rGO in γ-Fe2O3 in 1 M KOH electrolytic solution. The

maximum specific capacitance of 82.5 F/g was observed from charge-discharge method at 1 Ag-1

current density for the composition of Fe2O3 with 0.2% rGO. Thus, synthesized γ-Fe2O3/rGO nano-

composite may be a good electrode material for energy storage and supercapacitor applications.

-1.2 -1.0 -0.8 -0.6 -0.4 -0.2 0.0

-0.05

-0.04

-0.03

-0.02

-0.01

0.00

0.01

25 mV/s

Fe2O

3(0.2% rGO)

Fe2O

3

Fe2O

3(0.1% rGO)

Cu

rre

nt D

en

sity (

Ag

-1)

Potential (V)

-1.2 -1.0 -0.8 -0.6 -0.4 -0.2 0.0

-0.06

-0.04

-0.02

0.00

0.02

50 mV/s

Cu

rre

nt (m

A)

Potential (V)

Fe2O

3(0.2% rGO)

Fe2O

3

Fe2O

3(0.1% rGO)

Figure: CV graphs of γ-Fe2O3 with different concentrations of rGO

References:

1. H. E. Ghandoor, H. M. Zidan, M. H. Mostafa, M. I. Khaliland, M. Ismail, Int. J. Electrochem. Sci., 7

(2012) 5734 – 5745.

2. Y.G. Dongling, W. T. Wang, D. J. Wei, X. Yan, L. Y. Cao, Y. T. Liu, Electrochimica Acta, S0013-

4686 (2016) 30071-8.



25th


56

Meteorological parameters modulate Chikungunya and Dengue

occurrences in India (2010- 2016)

Avinash A Patil1, Dilip R Kothawale

2 and Pratip Shil

1*

1 ICMR - National Institute of Virology, 130/1 Sus Road, Pashan, Pune 411021 INDIA

2 Indian Institute of Tropical Meteorology, Homi Bhabha Road, Pashan, Pune 411021. INDIA

Correspondence: [email protected]


Abstract:

Climate change is a reality and along with it came the global surge in mosquito-borne viral

diseases like Zika, Dengue , Chikungunya, etc. India has a huge burden of Dengue and Chikungunya

with more than 10 million individuals affected between 2010 and 2016. This necessitated research to

understand the role of environmental and meteorological parameters in the spread of these diseases. In

the present project, we have compared the all India occurrences (confirmed cases) of dengue and

chikungunya with meteorological factors like Maximum and minimum temperatures, rainfall, etc.

Meteorological data were procured from IMD and IITM. Disease data was obtained from National

Vector Borne Disease Control Programme (NVBDCP) [1] and Infectious Diseases Surveillance

Programme (IDSP) [2] of the Government of India. It was observed that in the states Maharashtra and

Karnataka, most affected by Chikungunya, the number of annual occurrences were modulated by

area-weighted average annual rainfall [3]. The Area weighted average annual rainfall (ARF) was

calculated by Thiessen method:

𝐴𝑅𝐹 = ∑ 𝑋(𝑖) × 𝐴(𝑖)𝑛

𝑖=1

∑ 𝐴(𝑖)𝑛𝑖=1

where X(i) is the average annual rainfall for any (i th) meteorological sub-division and A(i) is the

area in sqKm for the (i th) sub-division and n is the number of sub-divisions covering any particular

state of India [4]. Mathematical analyses and statistical calculations performed in R software at NIV

Pune.

Spatio-temporal analyse revealed the distributions of rural outbreaks of Dengue and

Chikungunya across India. Rainfall was found to be the principal factor that modulated dengue and

chikungunya occurrences across India. Details will be presented in the poster.

25th


57

A B

C)

Figure 1: A) Dengue occurrences in the Indian states. B) Rural outbreaks of Chikungunya over the

years.

References:

1. NVBDCP webpage: www.nvbdcp.gov.in

2. IDSP website. Weekly reports. www.idsp.nic.in

3. P Shil. et al. VirDis 2018, 29(1): 49 - 56.

4. AH Theissen, et al. Mon. Weath. Rev. 1911; 39(7) : 1083.

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58

Study of Cu2O Thin Film Synthesis by Electrochemical Deposition Method

for Solar Cell Application

Pooja Galandea, Maya Dangat

a , Jayashri Dawange

a, Avinash Rokade

a and Sandesh

Jadkarb

aProf. Ramkrishna More Arts, Commerce and Science College, Akurdi, Pune-411044,

bDepartment of Physics, Savitribai Phule Pune University, Ganeshkhind, Pune-411007


Abstract: Cu2O thin films are successfully synthesized on FTO substrate by using electrochemical deposition

method. Electrochemical deposition is one of the best methods adopted for the synthesis of thin film

under ambient conditions. Cu2O is an important P-type semiconductor with wide potential

applications in various technologies such as solar cells, photocatalysis, batteries, sensors and optical

devices[1-4].The electrodeposition of copper oxide onto FTO coated glass substrate was studied in 10

Mm hydrated CuSO4 aqueous solution at various applied voltages from -0.3 V to -0.7 V. The

electrochemical deposition was carried out in an electrochemical cell with FTO as the working

electrode and carbon as the counter electrode. The influence of electrochemical deposition parameters

on the electrical, structural and morphological characteristics of deposited films were studied in detail

using Raman, UV Visible spectroscopy, XRD, Scanning Electronic Microscopy.

Figure: Scanning Electron Micrograph of Cu2O thin films deposited by electrochemical deposition

method.

References:

1. S. Akimoto, K. Ishizuka, M .Yanagita, Y. Nawa, G. Paul, T. Sakurai, Solar cell, 80 (2006)

715.

2. P. Poizot, S. Laruelle, S. Grugeon, L. Dupont, J. MTarascon, 407 (2000) 496.

3. H. Zhang, Q. Zhu, Y. Wang, L.Zhao, B.Yu, 18 (2006) 867.

4. F.Xu, M. Deng, G. Li, S. Chen, L. Wang, Electrochemica Acta 88 (2013) 59. .

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59

Hafnia based gate dielectrics for MOS-FET

Vaibhav Walve and N. B. Chaure

Department of Physics, Savitribai Phule Pune University, Pune, 411 007 Presenting author: [email protected]

Abstract:

Hafnium- dioxide known as hafnia which is one of the most common and stable compounds

of hafnium. It is an electrical insulator with a band gap of 5.3~5.7 eV [1] and high dielectric constant

~25 which makes it useful as high K dielectrics in the emerging electronic industries. It has promising

properties for the use in MOS-FET as gate dielectric such as low leakage current, high-k value and

band offset [2]. Here we have synthesized hafnia powder by using hydrothermal route. The HfCl4

used as starting material and NaOH the pH of the solution was adjusted using NaOH. The product

was centrifuged to remove the byproduct obtained during the chemical reaction. The formed powder

was characterized Hf(OH)4 confirmed by XRD analysis, which agrees well with Wan and Zhou [3].

The obtained sample was dried under IR lamp with intensity ~10 mW/cm2for an hour. The hafnia thin

films were prepared from the solution by adding 100 mg HfO2 powder into 10 ml absolute ethanol.

The sample were annealed for 400 0C in Muffle Furnace for 120 min. the sample were characterized

using uv-vis, X-ray diffraction and scanning electron microscopy to study the optical. Structural and

morphological properties. The XRD reveled the growth of monoclinic crystal structure of Hafnia. The

size of the particles of HfO2 was measured ~100nm by using the SEM. The prepared powder can be

used to blend in the PVA to get the high dielectric thin films onto flexible substrate for flexible

displays.

Figure: A) SEM Images of HfO2 thin films, B) XRD Analysis of HfO2 thin films,

C) Tauc plot for Bandgap determination

Refferences:

1. Bersch and Eric, Band offsets of ultrathin high-k oxide films with Si. Phys. Rev. B. 78,

085114(2008),6-7.

2. J. Robertson, High dielectric constant oxides, Eur. Phys. J. Appl. Phys. 28(2004), 265–291.

3. Yingying Wan and Xingping Zhou, Formation mechanism of hafnium oxide nanoparticles by a

hydrothermal route, RSC Advances, 7(2017), 7763–7773.

20 30 40 50 60 70 80

0

500

1000

1500

2000

2500

3000

3500

Inte

ns

ity

(a

rb. u

nit

)

2 (Degree)

(011)

(111)

(111)(020)

(002)

(120) (112)

(202)

(220)

(022)

(311)(131)(203)

(312)(222)

B

4.0 4.5 5.0 5.5 6.0 6.5

0.00E+000

2.00E+014

4.00E+014

6.00E+014

8.00E+014

1.00E+015

(h)2

(eV

/m)2

h(eV)

Annealed Powder

As Prepared Powder

5.62 5.65

C

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60

Synthesis And Characterization of Graphene Oxide and Reduced

Graphene Oxide for Gas Sensing Study

Aditi Dave, Namrata Bhamre, Amol Vedpathak and Sunita Bhagwat

Department of Physics, Abasaheb Garware College, Karve road, Pune-411004

Presenting Author: [email protected]

Corresponding Author: [email protected]

Abstract:

Graphene is currently under evaluation for a wide range of applications, which will benefit from its

unique combination of excellent mechanical, electronic, optical and chemical properties. GO and rGO

can be used in various material applications including light emitting devices (LED), touch panels,

solar cells etc. rGO is the form of GO that is processed by chemical, thermal and other methods in

order to reduce oxygen content while Graphene Oxide is a material produced by oxidation of graphite

which leads to increased interlayer spacing and fictionalization of the basal planes of graphite. GO

was prepared using improved Hummers method whereas the produced GO was subjected to chemical

reduction with the use of hydrazine hydrate. GO and rGO has different morphologies and functional

groups. SEM study shows wrinkled, layered flakes and thin sheets on GO and rGO surface

respectively. The samples were further characterized by XRD, FTIR techniques for the confirmation

of structural and morphological properties. The gas and humidity sensing characteristics of GO and

rGO were carried out.

Figure: (a) XRD of Graphite, GO and rGO (b) SEM of Graphite (c) GO (d) rGO

References:

1. S.N. Alam, N. Sharma and L. Kumar, Graphene, 6, (2017), 1-18.

2. A.M. Dimiev and J.M. Tour, ACS Nano, 8(3), (2014), 3060–3068.

(a) (b) (c)

(d)

(d)



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Study of structural, electronic and magnetic properties of pure and doped

(Fe2O3) n cluster

Dr. D. L. Lalsare, C. Chavan

H. P. T. Arts & R. Y. K. Science College, Vidyanagar, College Road, Nashik, 422005


Abstract:

In the present work, we report the structural, electronic and magnetic properties of (Fe2O3) n clusters

with its units ranging from 1 to 10, determined using Density functional theory (DFT). The Fe2O3

smaller clusters exhibit drastically different properties than that of the bulk material, due to the

difference in sizes. The changes in minimum structural energy, atomic forces, magnetic moment with

changes in geometries of same units are studied. Also the variations in these properties with

increasing cluster sizes n=1-10, are being observed. The (Fe2O3) n cluster is considered in pure form

and doped form with other transition elements. The results are shown by different cluster geometries,

total and spin charge density plots, density of states (DOS) plots and partial charge density plots.

References:

1. A. Erlebach, C. Hühn, R. Jana, and M. Sierka; Physical chemistry chemical physics, Issue 48,

2014

2. Max C. Holthausen, Wolfram Koch; A Chemist's Guide to Density Functional Theory

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62

Synthesis of Nano-Crystalline CdS thin films by using Hot Injection

method For Harvesting Solar Radiation

Kiran Shindea, Supriya Koyale

a, Bharat Bade

b, Adinath Funde

b, Sandesh Jadkar

b and

Avinash Rokadea




Abstract

In the present work, we have successfully synthesized nano-crystalline CdS thin films by using Hot

Injection method. Cadmium sulfide, whose optical band gap is 2.4 eV, is used as an n-type

semiconducting material.[1] Therefore, its usefulness is found in photovoltaic cells, photo-catalysis &

solid state optics. Here hot injection method was incorporated for the preparation of CdS nano-

crystals, & thereafter, using doctor blade technique, nano-crystalline CdS thin films was deposited on

the glass substrate. The precursors used for cadmium was CdCl2 while that for sulphur was sulphur

powder. The effect of variation in molarity is investigated in this work. Formation of CdS thin films

has been confirmed by XRD, Raman, UV-Visible absorption spectroscopy, and scanning electron

microscopy which characterizes phase, composition quality and optical properties. The overall

improved crystalline structure of CdS thin films at higher sulphur molarities is obtained and it is

revealed from XRD pattern showing the orientation along (002) plane.

Figure: XRD spectra of CdS thin films for various sulphur molarities.

References: 1. N. Bao, L. Shen , T. Takata , K. Domen; Chem. Mater., 20 (2007) 110. 2. C. Li, J. Yuan, B. Han, W. Shangguan, Int. J. Hydrogen Energy 36 (2011) 4271–4279.

3. X. Li, J. Yu, M. Jaroniec, Hierarchical photocatalysts, Chem. Soc. Rev. 45(2016) 2603–2636.

4. Q. Xiang, B. Cheng, J. Yu, Appl. Catal. B—Environ. 138–139 (2013) 299–303.

5. Y. Xu, X. Yin, Y. Huang, P. Du, B. Zhang, Chem.—Eur. J. 21 (2015) 4571–4575.

6. Y. Xu, W. Zhao, R. Xu, Y. Shi, B. Zhang, , Chem. Commun. 49 (2013) 9803–9805.

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Incorporation of Chemically Synthesized Cadmium Sulfide nanoparticles

on ZnO nanorods for to fabricate photoelectrode

Supriya Koyalea, Kiran Shinde

a Bharat Bade

b , Adinath Funde

a, Sandesh Jadkar

a and

Avinash Rokadea




Abstract

The CdS thin films were chemically synthesized by using Hot Injection technique. The CdS

semiconductor narrow band gap (~ 2.4 eV) is utilized as a visible active layer to decorate ZnO

nanorods to form a heterostructure for PEC application. Zinc oxide (ZnO) is an n-type semiconductor

with direct band gap energy of 3.37 eV at room temperature and the nanomaterials of ZnO exhibit

several distinct advantages such as simple tailoring of the structures, because of their suitable band

gaps, higher carrier mobility, facile and low-cost for large-scale manufacturing, stability against photo

corrosion, high photocatalytic activity and so on.[1, 2] Among various sensitizing materials, CdS has

been widely used because of its narrow direct band gap semiconductors and have suitable band

alignment with ZnO. The electrons are injected from conduction band of narrow band gap material to

the conduction band of ZnO leading to easy movement & collection of charge carriers.

CdS (nano-crystals) are synthesized by using the hot injection method and then incorporated for the

fabrication of CdS/ZnO photoelectrode, by using drop casting technique. The precursors used for

cadmium was CdCl2 while that for sulphur was sulphur powder and that of Zinc nitrate and HMT for

ZnO nanorods preparation. The effect of quantity of CdS added on ZnO nanorods is calculated for

better performance of fabricated photoelectrode in this work. The fabricated CdS/ZnO photoelectrode

was investigated from XRD, UV-Visible, Raman, SEM characterization & PEC measurement system.

We found enhanced photoactivity due to the sensitization of ZnO nanorods with CdS narrow band gap

materials.

Fig. 2. Raman spectra of ZnO and ZnO/CdS photoelectode.

References:

1. E. Kaidashev, M. Lorenz, K. Han and M. Grundmann; Appl. Phys. Lett., 82 (2003) 3901.

2. S. Xu, Z. L. Wang; Nano Res., 11 (2011) 1013.

3. Kumar et al. Nanoscale Research Letters 2012, 7:584

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Effect of RTP annealing on CIGS thin film deposited from single-step,

low-cost electrochemical technique

Sachin Desarada, Priyanka U. Londhe and N. B. Chaure

Electrocehemical Laboratory, Department of Physics, Savitribai Phule Pune University, Pune-411007


Abstract:

CuInGaSe2(CIGS) belongs to group I-III-IV have been continuously used as absorber

material towards the development of substrate and superstrate solar cell configuration due to its

various properties, such as direct bandgap, possibility to tune band gap, high optical absorption

coefficient (10-5 cm-1), chemical and electrochemical stability, etc. The highest efficiency reported

for CIGS substrate based solar cell is 22.9% obtained by vacuum deposition technique using various

post deposition treatments [1]. Several techniques have been used to deposit CIGS layers, among all

of them electrodeposition technique is one of the low-cost, easily scalable, high throughput technique

to grow the metal semiconductor and oxide thin films [2]. We have used non-aqueous

electrodeposition technique to deposit the thin films of CIGS and characterized thoroughly to study

the optical, structural, compositional and morphological properties. The cyclic voltammetry was used

to optimize the growth potential of CIGS.

The samples were grown at different potentials ranging from -0.8V to -1.1V and annealed

subsequently using rapid thermal annealing(RTP) Technique. XRD results revealed the three

prominent reflection of CIGS corresponds to (111), (204)/(220) and (116)/(312), SEM images

confirmed the growth of uniform void free and densely packed thin layer of CIGS. It was further

found that the deposition potential plays important role to control the stoichiometry of samples.

Refferences:

1. Wu JL, Hirai Y, Kato T, Sugimoto H, Bermudez V. 7th World Conference on Photovoltaic Energy

Conversion (WCPEC‐ 7), June 10–15, 2018, Waikoloa, HI, USA.

2. Priyanka U. Londhe, Ashwini B. Rohom, Rohan Fernandes, D. C. Kothari, and Nandu Chaure ; ACS

Sustainable Chemistry & Engineering 2018 6 (4), 4987-4995

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Enhanced photoelectrochemical performance of Bi2Se3 thin films: Effect of surfactant

N.D.Desai1, R.M.Mane

1, S.S Patil

1, L.P.Deshmukh

2,P.N.Bhosale

1

1 Materials Research laboratory, Department of Chemistry, Shivaji University, Kolhapur

2 UGC-BSR Faculty Fellow, Department of Electronic Science

Email id of presenting author:[email protected]

Abstract:-

In the present investigation been successfully deposited by using arrested precipitation technique (APT) at room

temperature. The effect of three different surfactants on the optostructural, morphological, compositional and

photoelectrochemic study reveals direct and allowed transition with a band diffraction pattern (XRD) confirms

rhombohedral crystal structure of micrographs shows morphologica topography of Bi2Se3 thin films was

determined by AFM. Compositional ana presence of bismuth and selenium performance with highest efficiency

1.47%. In order to study the stability of Bi four cycles are repeated after gap of one week each. In order to

confirm the charge transport mechanism EIS measurement is also done.

Keywords:- Thin films, APT, Effect of surfactant, 1.47% PEC

Graphical Abstract:

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66

Conductive Polypyrrole as a Ammonia Gas Sensor

Novman Nabeel and Sunita Bhagwat

Department of Physics, Abasaheb Garware College, Karve Road, Pune 411004, India



Abstract:

Polypyrrole (PPy) is a type of organic polymer formed by the polymerization of monomers of pyrrole.

Polypyrrole has excellent thermal stability, good electrical conductivity and environmental stability.

PPy was synthesized by chemical oxidative polymerization method using Ferric chloride (FeCl3) as an

oxidizing agent and surfactant CTAB in aqueous solution. Pyrrole (0.5M) to oxidant (FeCl3) molarity

ratios were varied in different (1, 1.5, 2, and 2.5). It was found that increasing FeCl3 up to 2 M

increases PPy’s conductivity. Therefore, 2M could be an optimum concentration. PPys were

characterized using X-Ray Diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy and

Scanning Electron Microscopy (SEM). XRD studies show a broad peak in the region 2θ = 220-25

0 for

all the samples indicate the amorphous nature of the polymer and intermolecular stacking structure.

The FT-IR spectra of the PPy samples were recorded in the range of 400 to 4500 cm−1

to confirm

polymerization It confirms the polymerization of the monomer to polymer during the synthesis

process. The samples show sponge like morphology in SEM. The conductive natures of PPy were

studied by I-V characteristics. The best conductive polymer is studied for the NH3 gas response.

Figure: SEM of PPy for different ratios of monomer and oxidant

References: 1. Abdirahman Yussuf, Mohammad Al-Saleh, Salah Al-Eneziand Gils Abraham, International Journal of

Polymer Science 2018, 1- 8.

2. Hemant K. Chitte, Narendra V. Bhat, Vasant E. Walunj, Ganesh N. Shinde, Journal of Sensor

Technology, 2011, 1, 47-56.

0.5:1 0.5:1.5

0.5:2 0.5:2.5



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Study of effect of molarity of sulfur source on Cadmium Sulfide

nanoparticles synthesized by using chemical precipitation method Poonam Lawand

a, Nilam Jagtap

a Bharat Bade

b , Adinath Funde

a, Sandesh Jadkar

a

and Avinash Rokadea



Presenting author: 1) [email protected]

2) [email protected]

Abstract Cadmium sulfide (CdS) nanoparticles narrow bandgap (~2.4 eV) were synthesized by

chemical precipitation method using cadmium chloride (CdCl2), sodium sulfide (Na2S) and thiourea

as a solvent by varying temperatures from 160oC for 30 min and sulfur injected temperature between

80 to100oc after sulfur injects 230

oc for 30 minutes. [1] Also the effects of precursor molarity

variations were investigated to fix the optimum deposition conditions. The nanoparticles were

characterized by X-ray diffraction (XRD), Raman spectroscopy, field emission scanning electron

microscopy (FE-SEM), energy dispersive spectroscopy (EDS), High-resolution transmission electron

microscopy (HR-TEM) and UV-Visible spectroscopy. XRD pattern revealed cubic crystal structure

for all the synthesized CdS nano particles. The analysis of characterization techniques confirmed the

formation of nanocrystalline CdS thin film with uniform size of nanoparticles & composition

throughout sample.

Figure: XRD spectra of CdS thin films for various sulfur & thiourea molarities.

References: 1. N. Bao, L. Shen, T. Takata, K. Domen; Chem. Mater., 20 (2007) 110.

2. A. Mercy, K. S. Murugesan, B. M. Boaz, A. J. Anandhi, and R. Kanagadurai, Journal of Alloys and

Compounds 554, 189 (2013).

3. A. Mercy, R. S. Selvaraj, B. M. Boaz, A. J. Anandhi, and R. Kanagadurai, Indian Journal of Pure

Applied Physics 51, 448 (2013).

4. Y. Cao, P. Hu, and D. Jia, Applied Surface Science 265, 771 (2013).

5. V. Singh, P. K. Sharma, and P.Chauhana, Material Characterization 62, 43 (2011).

6. Y. Xu, X. Yin, Y. Huang, P. Du, B. Zhang, Hydrogen production on a hybridphotocatalytic system

composed of ultrathin CdS nanosheets and amolecular nickel complex, Chem.—Eur. J. 21 (2015)

4571–4575.

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68

Structural and Morphological Properties of Electrodeposited Bismuth

Telluride (Bi2Te3) Thin Films

Khairnar V.S.a, Patil S.V.

b, Kulkarni A.N

b, Lonikar V.V.

b, Gite A.B

c, Waghmare R.V.

a

aDepartment of Physics, Vidya Bharti Mahavidalaya, Amravati-444602, India.

bDepartment of Physics, School of Science, Sandip University, Nashik-422002, India.

cDepartment of Physics, SNJB’S Art and Science College, Nashik-422101, India.


Abstract:

Present work deals with the electrodeposition of Bi2Te3 thin films. Structural, elemental and

surface morphological analysis of deposited films have been caused out using XRD and SEM

with EDXs techniques. XRD contributes the formation of Bi2Te3 crystals with crystalline

size in the range of 5nm to 9 nm. EDXs is in agreement with X-ray diffractometer and

confirms the qualitative formation of Bi2Te3 in the stoichiometry of 2:3. Scanning electron

microscope reveals the uniform spherical morphology for the deposited films.

Figure: SEM image of Bi2Te3 thin film at 60 min.

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69

Design and Development of low cost Arduino based Successive Ionic Layer

Adsorption and Reaction (SILAR) Coating System with magnetic stirrer

using discarded Lab Equipments

Suhail A. A. R. Sayyeda,b

, Niyamat I. Beedria, and Habib M. Pathan

a

aAdvanced Physics Laboratory, Department of Physics,

Savitribai Phule Pune University, Pune – 411 007, Maharashtra, India bDepartment of Physics, B.P.H.E. Society’s Ahmednagar College,

Ahmednagar – 414 001, Maharashtra, India Presenting author: [email protected]

Abstract:

The present work deals with design and development of low cost Arduino based Successive

Ionic Layer Adsorption and Reaction (SILAR) coating system using discarded lab equipments such as

spectrometer, travelling microscope, and dc motor of computer cooling fan. Amongst the different

thin film deposition techniques, SILAR method is relatively simple with wide range of advantages

such as; relatively uniform thin films on various substrates of different shapes with controlled

deposition rate and film thickness can be obtained, unlike vacuum deposition systems does not require

costly systems, deposition can be carried out at low temperatures [1-3]. The actual SILAR coating

system is costly. Various researchers have reported low cost Microcontroller / Arduino based SILAR

system [1, 4-7]. In the present work (as shown in Figure) we have used Arduino for controlling two

stepper motors and one dc motor using driver circuits. Using stepper motor with driver 1 the position

of the beakers is controlled. Using stepper motor with driver 2, the dipping time is controlled by

using suitable delay. And dc motor with driver 3 is used to stirrer the solution by changing magnetic

field by moving a small magnet attached to the rotor of dc motor.

Figure: Schematic of SILAR with magnetic stirrer

References:

1. H. M. Pathan and C. D. Lokhande; Bull. Mater. Sci., 27-2 (2004) 85.

2. S. Lindroos, A. Arnold, and M. Leskela; Appl. Surf. Sci., 158 (2000) 75.

3. Y. F. Nicolau, M. Dupuy, and M. Brunel; J. Electrochem. Soc., 137 (1990) 2915.

4. M. S. Patil and S. K. Jathar; Proceedings of 36th

IRF International Conference, 28th

May, 2017,

Bengaluru, India.

5. https://www.youtube.com/watch?v=0hdQSz4PJZo

6. https://www.youtube.com/watch?v=0ecjflo5VPQ

7. https://www.youtube.com/watch?v=fM6EPolQMug


https://www.youtube.com/watch?v=0hdQSz4PJZo

https://www.youtube.com/watch?v=0ecjflo5VPQ

https://www.youtube.com/watch?v=fM6EPolQMug

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Co-deposited Sn-Ag-Cu films for Fine Pitch Surface finishes in PCBs

Varsha Pawane a

Shraddha Rakshe b, Shany Joseph

a and Girish Phatak

a

a Centre for Materials for Electronics Technology, Panchwati, off Pashan Road, Pune-411008

b Department of Electronic science, Savitribai Phule Pune university , Pune- 411007


Abstract:

Surface finishing of PCBs help in protecting the Cu pads till the SMT processes are done to

mount thecomponents on the circuit board. It could take even upto an year before the surface

mount devices are attached. It is therefore important that the Cu pads are protected till the

components are soldered and attached. Hot Air solder levelling (HASL) process is the most

commonly used process for the surface finishing of the PCBs. This process involves dipping

of the patterned PCBs in the molten solder wherein the pads get covered with solder. A well

set up process, HASL has minimal issues and is economical for the commercial applications.

But with the circuits going denser and complex the requirement becomes stringent. HASL

poses some issues as the pitches become finer. Non planarity and solder bridging are the

critical issues [1]. During dip coating of the pads into the molten solder it is observed that the

thickness of the solder deposited on the pads are varying. And sometimes when the pads are

closer ( Fine pitch boards) occurrence of solder bridging is also observed. Electroplating

process provides a solution to these issues. It is possible to control the uniformity and

thickness of the deposit by controlling the deposition parameters like the current density, time

and also the bath composition. Since the patterning of the PCBs are done using

photolithography process it is possible to develop a fine pitch board using electroplating

process for surface finishing. There has been an increasing demand for using lead-free alloys

owing to the health hazards posed by the use of lead. Sn-Pb alloys have been the most sought

after solders and has been a benchmark while selecting and comparing the various lead free

alloys. Sn based alloys with minute addition of elements like Ag, Cu, Bi, Zn Co etc have

been studied. Binary and ternary alloys of Sn with Ag and Cu are the most preferred ones [2].

This paper reports our studies on co-deposition of Sn-Ag-Cu alloys using a single co-

deposition bath containing the three metal ions. Formulation of a co-deposition bath for this

ternary system has challenges of its own. Sn 2+ ions due to their highly reducing tendency

cause precipitation of the nobler Cu 2+ and Ag + ions in the bath itself. Mutually compatible

bath chemicals including chelating agents, additives, brighteners etc have to be identified [3].

The metal salts and their chelatingagents should be chemically compatible with each other in


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71

order to obtain a clear and stable bath. The bath pH also is critical to the stability of the metal

chelates. We have attempted formulation of a ternary Sn-Ag-Cu based co-deposition bath and

their properties are being evaluated. The bath uses citric acid as chelating agent along with

other additives. The bath is found to be stable and the effect of additives and deposition

parameters are being studied. Electrodeposition trials were carried out. One hour of

electroplating at 5mA/cm2 produced the ternary alloy film of Sn-Ag-Cu of 25µm thickness.

The microstructure and elemental analysis of the film was evaluated using SEM-EDAX.

Figure 1 presents the microstructure of the film. The film was found to be crystalline and

compact with a grain size of 1-2µm. Electrochemical studies using cyclic voltametry helps to

identify the reduction mechanism as well as the potential range in which the alloys are

depositing. Cyclic Voltametry (CV) studies were carried out using Potentiostat- Galvanostat.

Figure 2 presents the CV curve for the ternary bath system. As can be seen from the CV

curve, there is only one reduction peak at -188mV which shows that the three metals are

getting deposited in a single step in a very narrow range of potential. We can infer that the

chelating agent is effectively modifying the deposition potentials of Sn, Ag and Cu ions and

bringing them close together such that all the three metals are getting co-deposited in the

films. These chelating agents form complexes with the metal ions and help in multiple ways.

The chelates restrict the concentration of free metal ions in the bath and prevent the bath from

precipitating [4]. By chelation these metal ions are held in reserve and these ions get released

as the deposition progresses. With appropriate selection of chelating agents and other bath

additives [5] the co-deposition bath helps to better control the film composition as compared

to the processes of plating each metal ion separately in individual baths.

Figure1:SEM Microstructure of Sn-Ag-Cu film

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72

Figure 2: Cyclic voltammetry of Sn-Ag-Cu bath

The effect of deposition parameters as well of various bath additives on the microstructure and

composition of the film and the bath stability would be studied and reported. The consistency of the

bath and the repeatability of the results would be studied.

References:

1. Hugh Roberts, Kuldip Johal in lead free Soldering, Springer US, 2007, pp 223

2. Yingxin Goh, A.S.M.A. Haseeb and Mohd Faizul Mohd Sabri, Soldering & Surface

Mount Technology 25/2 (2013) 76– 90

3. Shunfeng Cheng, Chien-Ming Huang, Michael Pecht, Microelectronics Reliability 75

(2017) 77-95

4. Stojan Djokić, Bioinorganic Chemistry and Applications, Hindawi Publishing

Corporation, Volume 008, Article ID 436458 1-7

5. Shany Joseph and Girish Phatak, Materials Science and Engineering B 168 (2010) 219–223

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73

Synthesis and Characterization of L-Histedine modified biocompatible

ZnO Nanoparticles

Priyanka Bhosale and Sunita Bhagwat




Abstract:

Zinc Oxide nanoparticles exhibit antibacterial, antifungal, anti-corrosive and UV-filtering properties.

The synthesis of ZnO nanoparticles in the presence of capping agents with the perspective of

biological applications has attracted widespread attention recently. L-Histedine is a conditionally

essential amino acid. Both plant and animal proteins are good sources of this amino acid, which is a

building block of protein in our body. ZnO nanoparticles capped with the biocompatible amino acid

(L-Histedine) are synthesized by wet chemical method which is cost effective and simple technique.

The procedure was carried out in the presence and absence of 0.0125M, 0.025M, 0.05M L-Histedine.

The structural, morphological and optical properties were further investigated.

Every plant like any organism needs certain components for growth over and above soil, sun, rain,

and air. The basic component of living cell is protein. Proteins are formed by sequence of amino acid.

The effect of L-Histedine (amino acid) modified ZnO nanoparticles were used as a protein for the

germination of seeds and its growth as a function of modified ZnO nanoparticles was observed.

Figure: SEM imagesof (a) ZnO nanoparticle and L-histidine modified ZnO

nanoparticle with different molarities (b) 0.0125M (c) 0.025M(d) 0.05M L-Histedine

doped ZnO nanoparticles

Refrences:

1. V.G. Sreevalsa, P.P. Jeeju, M.S. Augustine, K.M. Anilkumar, S. Jayalekshmi, Journal of Experimental

Nanoscience, 8, 2013, 937 -946.

(b)

0.0125M

M

0.025M 0.05M ZnO


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74

Equivalence of One Loop Feynman Diagrams in Covariant and Light-

Front QED

Deepesh Bhamre, Anuradha Misra

Department of Physics, University of Mumbai, Santacruz (E),Mumbai 400104, India

ABSTRACT:

Dirac, in his 1949 paper, described three forms of relativstic dynamics viz. the instant form,

the point form, and the front form [1]. In the front form of dynamics, the variables x+ = x0 +

x3 and x− = x0 −x3 are defined as the light-front time and longitudinal space variables

respectively along with the transverse space variables that are same as of the instant form, and

the evolution of a dynamical system with x+ can be studied. Correspondingly, k− and k+

become the light-front energy and longitudinal momentum respectively. The framework of

covariant field theory is based on perturbative treatment which is not very effective if bound

state calculations of relativistic systems in the strong interaction regime are to be performed.

However, a Hamiltonian formulation of field theory quantized on the light-front is a

promising candidate for such calculations. Thus, to prove the equivalence of covariant field

theory and Hamiltonian light-front field theory becomes an important step for carrying this

program forward. In Ref.[2], the one loop expressions for self-energy, vacuum polarization

and vertex correction were calculated using old fashioned Hamiltonian perturbation theory

starting with the light-front Hamiltonian P−. In order to prove equivalence of covariant theory

with the

above approach, the authors in Ref.[3], starting with the covariant expressions of the above

three corrections in QED, arrived at the expressions in the LF Hamiltonian approach by

performing k− integration using the method of residues in complex integration. This was

done for the cases of self-energy, vacuum polarization and the 0+0 component of vertex

correction. We, in our work, have established the equivalence between the two approaches (to

one loop Feynman Diagrams) by generalizing to all components of vertex correction [4]. In

order to establish equivalence, the form of gauge boson propagator to be used in the covariant

expressions of loop diagrams is an issue of utmost importance. This matter is being currently

investigated.

References:

[1] P.A.M. Dirac, Rev. Mod. Phys. 21, 392 (1949)

[2] D. Mustaki, S. Pinsky, J. Shigemitsu, and K. Wilson, Perturbative Renormalization of null-plane

QED, Phys. Rev. D, 43, 3411-3427 (1991)

[3] Anuradha Misra and Swati Warawdekar, Equivalence of covariant and light front QED at one

loop level, Phys. Rev. D, 71, 125011, (2005)

[4] Bhamre, D., Misra, A., Singh, V.K. Few-Body Syst (2018) 59: 107.

https://doi.org/10.1007/s00601-018-1431-6

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75

Synthesis and Characterisation of CdTe thin films prepared by

electrochemical technique

Dipmala P. Salia and N. B. Chaure

a

aDepartment of Physics, Savitribai Phule Pune University, Ganeshkhind, Pune, 411007


Abstract:

Cadmium Telluride (CdTe) belonging to group II-VI is direct band gap p-type material of band gap

1.45eV. It is robust material with high chemical stability and high optical absorption coefficient. It has

several applications such as used in radiation detector, infrared and x-ray imaging, Light Emitting

Diode (LED), Switching devices, light absorber material for thin film solar cells. Several deposition

techniques are used to deposit CdTe layers such as Pulsed Laser deposition (PLD)[1],Close-spaced

sublimation (CSS)[2], Magnetron Sputtering[3], Thermal Vacuum Evaporation (TVE)[4][6], Electron

Beam Vacuum Evaporation (EBVE)[5], Molecular Beam Epitaxy (MBE), chemical bath deposition

such as Electrodeposition[6] etc. Here, we have used electrodeposition technique to deposit

polycrystalline CdTe layers as it has several advantages such as to grow the uniform films over large

areas as well as irregularly shaped surfaces, no maintenance of equipment, toxic gaseous precursors

are not involved and low cost. Both aqueous and non-aqueous/organic solvents can be used. CdTe

thin films were electrodeposited using three electrode system on FTO coated glass substrate from

non-aqueous electrolyte. Cyclic voltammetry was used to optimize the growth potential of CdTe. The

samples were grown for -0.625V at temperature 140°C for 1 hour. The above samples were annealed

in muffle furnace at temperature 420°C for 20 minutes to enhance the homogeneity, grain size and

crystallinity of the layer. The samples were characterized using X-ray diffractometer, Raman

Spectroscopy, UV-Vis Spectroscopy, Scanning Electron Microscopy and Energy Dispersive

Spectroscopy to study the structural, optical, morphological and composition properties.

The energy band gap of samples was found to close to 1.45eV. The XRD analysis revealed the growth

of polycrystalline CdTe layer. Three prominent reflections (111), (220) and (311) were observed

around 23.8°, 39.5° and 46.6° respectively. For as- prepared sample the peak associated to metallic Te

was observed around 27.6°, which was further disappeared upon annealing of the sample. Highly

compact, uniform grain growth with globular surface morphology was recorded from SEM images.

Nearly stoichiometric thin films of CdTe were deposited at -0.625V was confirmed by EDS analysis.

These layers can be further used to prepare thin film solar cell devices.

Figure: XRD pattern of CdTe thin films (a) As-prepared, (b) Quenched, (c) Slowly cooled

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76

References:

1. Siying He et al., “Study of CdTe/ZnTe composite absorbing layer deposited by pulsed laser deposition

for CdS/CdTe solar cell”, Materials Science in Semiconductor Processing 67(2017), 41-45.

2. Kai Shen et al., “High efficiency CdTe solar cells with through-thickness polycrystalline CdTe thin

film”, RSC Adv., 2016, 6, 52326-52333.

3. M.A. Islama et al. “Fabrication of high efficiency sputtered CdS:O/CdTe thin film solar cells from

window/absorber layer growth optimization in magnetron sputtering”, Solar Energy Materials and

Solar Cells 172( 2017), 384-39

4. Ziaul Raza Khan et al., “Structural, optical, photoluminescence, dielectric and electrical studies of

vacuum-evaporated CdTe thin films”, Bulletin of Materials Science 35(2012), 169-174

5. Subhash Chander et al., “CdCl2 treatment concentration evolution of physical properties correlation

with surface morphology of CdTe thin films for solar cells”, Materials Research Bulletin 97 (2018),

128-135

6. N.B.Chaure et al., “Cd1−xZnxTe thin films formed by non-aqueous electrochemical route”,

Electrochimica Acta 54(2008), 296-304

https://www.sciencedirect.com/science/article/pii/S1369800117304821#!

https://doi.org/10.1039/2046-2069/2011

https://www.sciencedirect.com/science/journal/09270248


https://www.sciencedirect.com/science/journal/09270248/172/supp/C

https://link.springer.com/journal/12034



https://www.sciencedirect.com/science/journal/00255408/97/supp/C



https://www.sciencedirect.com/science/journal/00134686/54/2

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77

Fabrication of bilayer ZnO Compact/ZnO/In2O3 using SILAR method

Shital D. Satpute, Jyoti Jagtap and Habib M. Pathan*

Advanced Physics Laboratory, Department of Physics,

Savitribai Phule Pune University, Pune-411007


Abstract:

Dye-sensitized solar cell (DSSC) offers an efficient and easily implemented technology for future

energy supply. Compared to conventional silicon solar cells, it provides comparable power conversion

efficiency (PCE) at low cost material and manufacturing costs. DSSCs perform better under lower

light intensities, which make them an excellent choice for indoor applications.

In present work, we have studied structural and morphological properties of ZnO compact/ZnO/In2O3

bilayers considering their applications for 3rd

Generation Solar Cells. Compact layer of ZnO was

deposited on fluorine doped tin oxide using successive ionic layer adsorption and reaction (SILAR)

method whereas porous ZnO and In2O3 layers were deposited on compact ZnO layer by using Doctor

Blade method .XRD pattern depicted structural properties of ZnO and In2O3. XRD for In2O3 and ZnO

also confirmed cubic and hexagonal phase of crystal structures, respectively. Using Scherrer Formula

crystal size of ZnO and In2O3 were 34 and 40 nm, respectively.From UV visible spectrum,we

calculated band gap of ZnO,In2O3 and bilayer.Scanning electron microscope(SEM) image show

surface morphology of bilayer film as shown in figure(a)

Figure: (a)SEM image of bilayer film and (b) UV visible spectrum of ZnO, In2O3 and bilayer film

Acknowledgement: Authors are thankful to Department of Science and technology, New Delhi for

financial support under Solar Energy Research Initiative scheme.


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78

Structural, Optical and Gas Sensing Properties of Spray Deposited

Sn doped MoO3 Thin Films

Hakim Rizwan and Sunita Bhagwat

Department of Physics, Abasaheb Garware College, Karve road, Pune-411004, India



Abstract:

Molybdenum trioxide with an orthorhombic symmetry is one of the most interesting material due to

their optical and electrical properties. This material also has imperative properties such as gas sensor,

as catalyst and electronic devices etc. In this present work Sn doped MoO3 thin films were deposited

on a glass substrate using spray pyrolysis technique with Sn at molar ratios of 0, 0.15, 0.25, 0.5 to

improve the optical, electrical and gas sensing properties of MoO3. In additional to structural

investigation, UV-Vis and SEM measurement were carried out. X-ray diffraction studies show that all

Sn:MoO3 thin films crystallized in an orthorhombic phase with noticeable change in terms of Sn level.

The increase in lattice parameter with Sn doping can be related to the substitution between Mo6+

and

Sn4⁺ at substitutional and interstitial sites as well. SEM results show fiber network, in this fiber

network Sn atoms acquired the positions with increased doping level.

Figure: SEM images of Sn:MoO3 thin films at various molarities of Sn

References:

1. A. Boukhachem, O. Kamoun, C. Mrabet, Mannai. Materials Research Bulletin, 72 (2015) 252–263.

2. J. Kaur, V.D. Vankar, M.C. Bhatnagar, Thin Solid Films, 518 (2016) 3982–3987.

0

0.15

0.25

0.5



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79

Synthesis, characterization & bacterial activity of ZnO and Serine modified

ZnO nanostructures

Shraddha C. Mahakal1#

, Surekha Satpute2, Arun G. Banpurkar

1, Abhay V. Limaye

1,

Kiran P. Adhi1

1 Center for Advanced Studies in Materials Science & Condensed Matter Physics, Department of

Physics, Savitribai Phule Pune University, Pune 411007 India.2 Department of Microbiology,

Savitribai Phule Pune University, Pune 411007 India.


Abstract:

Chemical route was adopted to synthesize both ZnO and Serine incorporated ZnO[1]. For

synthesizing ZnO, which is used as reference, a solution (0.25M) Zn(NO3)2 was prepared in distilled

water. NH4OH was added drop wise till a white precipitate is observed. This solution was stirred

continuously at 1200C for 1 hr and 30 minutes. The precipitate was then centrifuged & washed several

times using distilled water, which was subsequently dried. The same procedure was carried out in the

presence of Serine for the synthesis of Serine incorporated ZnO. Four different concentrations of

Serine were used, ranging from 0.1 mg/mL to 1mg/mL during the synthesis of Serine incorporated

ZnO.

Different techniques have been used for the characterization of the synthesized powders. X-

ray diffraction pattern shows the formation of single phase wurtzite ZnO. No other phases were

observed. The average crystallite size of undoped ZnO & Serine incorporated ZnO was estimated to

be in the range of 40-60nm. The UV-visible spectrograph shows variation in band gap energy in

Serine incorporated ZnO[2]. The undoped and Serine incorporated ZnO were tested for their bacterial

activity. While undoped ZnO, as expected, shows antibacterial activity, Serine incorporated ZnO

interestingly shows pro-bacterial activity. Field emission scanning electron micrographs supports the

reduction in antibacterial activity of Serine incorporated ZnO.

Reference:

[1] U. Ozgur, J. Appl. Phys. 98 (2005), 041301.

[2] A. Brif, G. Ankonina, C. Drathen, B. Pokroy, Advanced Materials, 26(2014), 477-481.

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80

Heart Rate Variability Analysis

Minal Mahadev Kurane1, G. R. Kulkarni

2

1B.G. Bhopal college Pune.

2Department of Physics, Savitribai Phule Pune University, Pune 411007 India

Abstract:

In this industrial and urbanized era, we all are busy and we are not enough aware about our

health. With time, day by day our lifestyle is changing vigorously that we don’t know how

these things impact on our health.so I have specially focused on health of heart. Every

disorder, disease affects the functioning of heart. To check working of heart is going well or

not, the new technique is invented by medical physicist. i.e. ECG,ECG is electrocardiogram.

It measures electrical activities of heart and gives heart rate presents in the form of graph.

Heartrate rate variability is an important aspect because health and environment factors cause

many changes in functioning of heart. In this work, twenty healthy subjects between age

group 20-60 were selected .ECG signals were recorded using lead 2 positions with using

standard procedure. R_R interval of 100, were measured for every subject. Mean R_R

interval, standard deviation, heart rate were estimated. The result shows significant

interpersonal heart rate variability.

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81

Fe3O4/rGO nanocomposite and its Application

Tejal Meharwala, Sanjay Apte

b, Sunita Bhagwat

a and Bharat Kale

b

a Department of Physics, Abasaheb Garware College, Pune- b Centre for Materials for Electronics Technology, Pune.



Abstract:

rGO-based nanocomposite materials have drawn the serious attention of researchers due to their

remarkable applications in the field of energy storage. Many researchers have studied rGO/Fe3O4

nanocomposites for their supercapacitor applications. In their research, Fe3O4 has been added to rGO

to make nanocomposites and the properties have been studied. We are proposing one-step strategy to

prepare Fe3O4/rGO nanocomposites under hydrothermal conditions. Here, in the present work we

have prepared nanocomposite electrode material composed of iron oxide (Fe3O4) and reduced

graphene oxide. We report herewith the synthesis of Fe3O4/rGO nanocomposites by hydrothermal

method using different concentrations of rGO. The nanocomposite material was characterized using

X-ray diffraction and Raman spectroscopy. XRD reveals the formation of phase pure Fe3O4 and

presence of rGO have been confirmed by Raman spectroscopy. The average crystallite size calculated

by Debye Scherrer formula is 14 nm. The electrochemical study of the as-synthesized composite

material was explored using cyclic voltammetry and galvanostatic charge/discharge tests. Fe3O4/rGO

nanocomposites showed different specific capacitance at 0.2 Ag-1

, 0.5 Ag-1

and 1 Ag-1

. Specific

capacitance varies as per concentration of rGO in Fe3O4 in 1 M NaCl electrolytic solution. The

maximum specific capacitance of 20.27 F/g was observed from charge-discharge method at 0.2 A/g

current density for the composition of Fe3O4 with 1% rGO. Thus, synthesized Fe3O4/rGO

nanocomposite may be a good electrode material for energy storage and supercapacitor applications.

0.0 0.2 0.4 0.6 0.8 1.0-0.006

-0.005

-0.004

-0.003

-0.002

-0.001

0.000

0.001

0.002

0.003

0.004

Cu

rren

t (m

A)

Potential (V)

(Fe3O4+0.1 % rGO) (Fe3O4+0.5 % rGO) (Fe3O4) (Fe3O4)+1 % rGO)

20 mv s-1

0.0 0.2 0.4 0.6 0.8 1.0-0.010

-0.008

-0.006

-0.004

-0.002

0.000

0.002

0.004

0.006

(Fe3O4+0.1 % rGO)] (Fe3O4+0.5 % rGO) (Fe3O4) (Fe3O4+1 % rGO)

Cu

rren

t (m

A)

Potential (V)

50 mv s-1

Figure: CV graph of Fe3O4 with different concentration of rGO

References:

1. J. Su, M. Cao, L. Ren , C. Hu, Journal of Physical Chemistry, 115 (2011) 14469–14477.

2. J. Su, M. Cao, L. Ren , C. Hu, Journal of Energy Chemistry, 25 (2016) 354–360.

3. F. Zhu, Y. Wang, Y. Zhang, W. Wang, Int. J. Electrochem. Sci., 12 (2017) 7197 – 7204.



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82

Effect of Photo-initiator Concentration on the Structural Resolution in

Two-Photon Lithography

Arun Jaiswala, Sumit Saxena

a, and Shobha Shukla

a

aIndian Institute of Technology , Bombay, Powai, Mumbai, MH, 494661


Abstract:

Two-photon lithography (TPL) has gained worldwide interest for the fabrication of sub-wavelength

2D & 3D micro/nano structures. TPL is based on two photon absorption (TPA). TPL relies on

specially designed molecules having large TPA cross section. Such molecules mainly include custom

designed two photon absorbing photoinitiators and two photon absorbing dyes. These engineered

molecules have high cost and most of the dyes are toxic. Photoinitiators are non hazardous and

cheaper as compared to dyes so are preffered for TPL. The phtoinitiator photolyzes into free radicals

after two-photon initiation and these radical in turn become responsible for the chain polymerization

of the monomers. By optimizing the concentration of the photo initiator and the laser power, sub-

wavelength features can be written inside polymer matrix. Here we have studied the effect of laser

dosage on the feature size of the fabricated structure and two and three dimensional microstructures

have been fabricated using optimized paramaeters.

.

25th


83

Study of soft (pre) annealing temperature effect on sputtered tri-layer

precursor CZTSthin film absorber for Photovoltaic’s

Ashvini Pundea, MamtaNasane

a, Subhash Pandharkar

a,Sandesh Jadkar

a,b

aDepartment of Physics, Savitribai Phule Pune University, 411 007

bSchool of Energy Studies, Savitribai Phule Pune University, 411 007


Abstract:

Kesterite Cu2ZnSnS4 (CZTS) is a very promising absorber material for low cost and high efficiency

thin film photovoltaic cells due to its direct band gap and to its high absorption coefficient. In the

present work, kesterite-CZTS absorber thin films were successfully synthesized from stacked tri-layer

precursor (ZnS/Sn/Cu) on Mo coated glass substrate through multitarget radio frequency magnetron

sputtering. Subsequently, stacked layers were soft annealed for different temperature from 200 to

350 °C for 1 hr in the atmosphere of argon (Ar) gas in order to improve intermixing of the elements.

Then, sulfurization was completed at 550 °C for 10 min in Ar (95%) + H2S (5%) environment in a

quartz tube furnace. X-ray diffraction and Raman spectroscopy analysis confirmed kesterite structure

of all deposited CZTS thin films. It is observed that, the average crystallite size of the CZTS depends

on the soft annealing temperature. Optical studies of films reveal small shift in band gap energy with

respect to soft annealing temperature. The surface morphology of the samples was examined using

scanning electron microscopy and it found to be dense microstructures. The systematic study on the

improvement in the properties of CZTS films using soft annealing temperature has been studied and

discussed.

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84

Characterization of Hydrothermally Synthesized MoSe2 Nanoparticles

Pratibha Pate and Sunita Bhagwat




Abstract:

Two-dimensional (2D) Transition Metal Dichalcogenides (TMDCs) have been considered as

promising candidates for next generation nanoelectronics, photonics, sensing, energy storage and

opto-elecronics, because of their atomically-thin structure and high surface to volume ratio. MoSe2

nanostructure materials have potential applications in solar energy conversion and nanoscale

electronic and optical devices. MoSe2 also used as photo-thermal agents in tumor therapy.

Ammonium molybdate and sodium selenite were used as starting material and ethylene diammine

(EDI) and distilled water used as solvent for the synthesis of MoSe2 nanoparticles. One-step

hydrothermal synthesis of MoSe2 nanoparticles was carried out at different ratios of EDI (1) to DI

water (1.5, 2.5, 3.5 and 5).

The structural and morphological studies of MoSe2 nanoparticles were carried out. XRD of all MoSe2

nanoparticles show Rhombo-centered Hexagonal structure. SEM images show cauliflower like

structure. On varying the concentration of EDI enhancement in grain size of MoSe2 nanoparticles is

observed.

Figure: SEM images of MoSe2 nanoparticles with EDI to DI water

References:

1. S. K .Balasingam, J. S. Lee and Y. Jun, Dalton Trans, 2015, 44, 15491– 98

2. X. T. Tran, S. Poorahong, M. Siaj, RSC Adv.2017, 7, 52345-52351

1:1.5 1:2.5

1:3.5 1:5


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85

Magnetic force microscopic analysis of the composite film of PLZT and

CZFO synthesized by Sol gel technique

AshwiniDatar@

, Bishakha Ray†, SuwarnaDatar

†, Vikas Mathe

@*,

@Department of Physics, Savitribai Phule Pune University, Ganeshkhind, Pune 411 007,

India. †DIATGirinagar, Khadakwasla, Pune, Maharashtra 411025, India.

Abstract: Understanding and designing the working of new electronic devices which have a coupling

between the magnetic and electric dipoles in multiferroic materials is very promising [1].In the

composite film the knowledge of the domain engineering is a key factor in understanding its magnetic

response [2]. This provokes the analysis of the magnetic force microscopy images with respect to the

variation in the insitu electric field applied to the sample and to explore the domain engineering

associated with it. Magnetic force microscopy is a very unique technique by which the domains can

be observed.

This work aims at analysis of the Magnetic Force Microscopy (MFM) phase images of the

composite films of Pb0.93La0.07Zr0.6Ti0.4O3 (PLZT) and Co0.9Zn0.1Fe2O4 (CZFO)when subjected to an

insitu voltage of 0V, ±2V and ± 5V. The images show that with applied voltage the contrast varies.

This variation seen can be attributed to the electric domain alignment due to the applied voltage. With

increasing voltage more and more domains get aligned along the direction of the field, thus exhibiting

a remarkable contrast in the images.

Keywords: Composite films, Sol gel, spin coating, PLZT, CZFO, MFM

Figure 1(a-f) shows the variation of contrast observed in the phase images for the

applied voltage (a) 0V (b) 2V (c) 5V (d) 0V (e) -2V and (f) -5V

References: [1] Y.Geng et al Nat. Mater. 13(2) 2014 163-167.

[2] Ashwini A Datar and Vikas L Mathe,J. Phys. D: Appl. Phys. 50 (2017) 485004 (11pp)

Acknowledgement:

Author Mrs. Ashwini A. Datar is thankful to the Department of Science and Technology for the support to carry

out this work under the WOS-A scheme (SR/WOS-A/PS-42/2013).

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86

The role of sulfurization temperature on sputtered CZTS thin film

absorber for Photovoltaic’s

Mamta Nasanea, Ashvini Punde

a, Subhash Pandharkar

a, Sandesh Jadkar

a,b

aDepartment of Physics, Savitribai Phule Pune University, 411 007

bSchool of Energy Studies, Savitribai Phule Pune University, 411 007


Abstract:

Copper zinc tin sulfide (CZTS, Cu2ZnSnS4) is a low band gap semiconductor that is attractive for use

in solar cells. Stacked precursors of Cu, Sn, and ZnS were fabricated on Mo coated glass substrates

by multi-target radio frequency magnetron sputtering system. We investigated the dependence of the

structural, optical and morphological properties of CZTS thin films on used sulfurization temperature

between 450 °C to 600 °C. X-ray diffraction and Raman spectroscopic measurements confirmed that

the films were composed of CZTS. At higher sulfurization temperature (600 °C) found secondary

phase of MoS2 which may affect on our solar cell efficiency. The grain size and crystallinity of the

films increased with sulfurization temperature. The films sulfurized at 550 °C showed a prominent

kesterite phase with a nearly stoichiometric composition, dense microstructure with the desired

thickness, and optical band gap energy of 1.5 eV. We have succeeded in obtaining high-quality

polycrystalline CZTS thin films by sulfurization under Ar (95%)+ H2S (5%) higher than atmospheric

pressure. Our results show that control of sulfurization temperature is an important factor in

optimizing the performance of CZTS thin films in solar cells.

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87

Synthesis, Characterisation And Applications of A Versatile Coordination

Complex – Potassium Trioxalato Ferrate (Iii) Trihydrate

Prof. (Dr.) Avinash S. Kumbhara, Dr. Lokesh P. Sharma

b, Siddharth S. Karkhanis

c

aDepartment of Chemistry, S.P. Pune University, Pune, 411007,

bDepartment of Microbiology, H.P.T. Arts & R.Y.K. Science College, Nashik, 422005,

cDepartment of Physics, H.P.T. Arts & R.Y.K. Science College, Nashik, 422005,


Abstract:

The present research includes synthesis, characterization & applications of a homoleptic bidentate

coordination compound, potassium trioxalato ferrate trihydrate by the precursor method[1]

.

Synthesized iron complex was characterized using UV-Visible spectrometry, FTIR Spectroscopy[2,3]

& X-ray diffractometry[4]

for elemental, structural & crystallographic analysis. It is a light sensitive,

polycrystalline complex of an emerald green color which is water soluble at 27°C to 37°C but

insoluble & crystallizes in cold water.

The light sensitivity of the complex refers to the fact that upon exposure to light of an appropriate

wavelength (<400nm) the iron complex undergoes an intermolecular redox reaction in which the

Fe(III) is reduced to Fe(II) while one of the oxalate ligand is oxidized to CO2. Due to the light

sensitivity, photochemistry & elemental composition of the complex we can list numerous

applications[5,6]

of the same in the various disciplines of sciences. During this work the potassium

ferrioxalate was analyzed for a few of applications viz. chemical actinometery, synthesis of Prussian

blue color pigment, antibacterial activity[7]

against the standard species of Gram positive and Gram

negative bacteria & preparation of traditional blueprint paper.

References:

2. Blair JC, Jones EM. H.S. Booth (Ed.) Inorganic Synthesis, vol. 1, McGraw-Hill Book Co. New York

1939; 35

3. Coates J, Interpretation of Infra-Red Spectra: A practical approach. R.A. Meyers (Ed.) John Wiley &

Sons Ltd, Chichester 2000. Encyclopedia of Analytical Chemistry; 10815–10837

4. Nakamoto K, Fujita J, Tanaka S, Kobayashi M. Infrared spectra of metallic complexes.IV. Comparison

of the IR spectra of unidentate & bidentate metallic complexes. JACS. 1957;79(18):4904-4908

5. Saritha A, Raju B, Ramachary M, Raghavaiah P, Hussain KA. Synthesis, crystal structure and

characterization of chiral, three-dimensional anhydrous potassium tris(oxalato)ferrate(III). j. phys. B

2012; 10:1016

6. Spencer HE, Schmidt MW. J. Phys. Chem. 1971; 75:2986

7. Armenatano D, Munno GD, Lioret F, Julve M. Cryst. Eng. Commun. 2005; 7:57

8. Prachayasittikul S, Suksrichavalit T, Isarankura-Na-Ayudhya C, Ruchirawat S, Prachayasittikul V.

Antimicrobial and antioxidative activities of 1-adamantylthio derivatives of 3-substituted pyridines.

Excli J. 2008; 7:63-70

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88

SILAR Deposited ZnO Nanorods for Biomedical Application

S. D. Pawar, Priyanka M., G.R. Kulkarni,

P.V. Baviskar, H. M. Pathan

Department of Physics, Savitribai Phule Pune University, Pune 411-007


Abstract:

Nano structured metal-oxides have been broadly studied to develop biosensors with high

sensitivity, fast response times, and stability for the determination of glucose. Here in this proposed

work, we have deposited ZnO nanorods by simple chemical route and studied as a Glucose biosensor

for biomedical application.

ZnO seed layer were chemically deposited on a pre-cleaned glass substrate using simple and

cost effective Successive Ionic Layer Adsorption and Reaction (SILAR) followed by air annealing at

300 oC. Hexagonal, wurtzite structure of ZnO was confirmed using X-ray diffraction analysis. UV-Vis

Spectrophotometer was used for the measurement of transmittance and absorption spectra, enabling to

deduce the important optical constants. From the optical adsorption spectrum, a band gap of 3.21 eV

was obtained which is comparable with the reported literature for ZnO. The surface morphology

deposited ZnO films were characterized using scanning electron microscopy (SEM). From SEM it

was observed that the deposited film shows the uniform growth over the substrate. SEM revealed the

morphology of ZnO is nanorods. The prepared ZnO nanorods will be used as a biosensor for glucose

detection.

Figure: ZnO Nanorods on pre-cleaned glass substrate using the SILAR method

Reference:

1. Ridhuan N. S.,Razak K. A.,& Lockman Z.,Scientific Reports, (2018)8:13722

2. Nikam P. R. ,Baviskar P. K.,Sali J. V., Gurav K. V. , Kim J. H. ,Sankapal B. R.,J Alloys

and Compounds, (2016)7:295

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89

Design and Development of a Resonator based Bio-sensor for bacteria

detection

Sweta Rath, Chetan Chavan, Vivek Kale, T.M. Bhave, S.N Kale*

Department of Applied Physics, Defence Institute of Advanced Technology, Girinagar, Pune, 411025

*[email protected] Presenting author: [email protected]

Abstract:

A non-invasive microwave based square-shaped complementary split ring resonator (CSRR)

is proposed, through this presentation, to detect gram-positive and gram-negative bacteria,

using a single sensor bed. The CSRR sensor is etched on the ground plane of a micro-strip

line using lithography technology. The sensing mechanism is based on interference of the

electromagnetic field around the resonator, which leads to a shift in the resonance frequency.

This shift depends on the dielectric constant of the material under test [1]. Upon

immobilizing a layer of various bacteria cultures as an antibody layer above CSRR structure,

the CSRR will respond to these bacteria in the form of a change in the resonance frequency

and power of the signal [2]. The CSRR bio-sensor can be made to a compact portable device

for on-site detection by integrating the sensor with an appropriate radio-frequency source and

detector, for which a transmitter-receiver of ~ 434MHz is chosen. The results are interpreted

in terms of the interaction of the electromagnetic radiations with the changing characteristics

of the sensor environment, typically with the antigen-antibody interactions.

References:

9. Boybay, M. S., & Ramahi, O. M. (2012). Material characterization using complementary split-ring

resonators. IEEE Transactions on Instrumentation and Measurement, 61(11), 3039-3046.

10. Rawat, V., Kitture, R., Kumari, D., Rajesh, H., Banerjee, S., & Kale, S. N. (2016). Hazardous materials

sensing: An electrical metamaterial approach. Journal of Magnetism and Magnetic Materials, 415, 77-

81.

25th


90

Raman Investigations on Graphite, Graphene Oxide (GO) and reduced

Graphene Oxide (rGO)

Poonam Borhadea, Nimrodh Ananth

b, Sunita Bhagwat

a and M.Niraj Luwang

b

Department of Physics, AbasahebGarware College, Pune – 411004

Chemical Engineering and Process Development Division, CSIR-NCL, Pune – 411008


Abstract:

Graphite is a 2D atomic thin layers of Graphene stacked in order of ABAB….Ideally, single

layered Graphene is a zero bandgap material because its valence band and conduction band meet at

the Dirac points. In experimental realizations, exfoliating single layer Graphene is a muchtedious task,

involves utilization of high end resource. So oxidizing graphite to graphene

oxide(GO)(semiconductive material) is a common viable process. GO is an oxidized form of

graphene containing few or multi layers of oxidized graphene sheet. One of the advantage of GO is its

easy dispersability in water and other organic solvents due to the presence of oxygen functionality.

Reduction of GO(rGO) means deoxygenation of GO via physical or chemical processes. The main

reason behind oxidation is to exfoliate and produce mono-to-few layer GO by increasing the

interlayer distance between the stacked graphene sheets.

The Raman Spectroscopy is a powerful tool in the structural characterization of graphite

material. The Raman Spectra of graphite and graphene oxide based materials usually show a D band

& a G band. The G band is common for all sp2

carbon forms, and it arises from the C-C bond stretch.

The G band in GO is shifted to a higher wavenumber due to the oxygenation of graphite, which

results in the formation of sp3

carbon atoms. The D band in GO is broadened due to the reduction in

size of the sp2 domains by the creation of defects, vacancies, and distortions during oxidation. This

work attempts to explain the characteristics peak of graphite and it's variations as a result of structural

modifications.

Figure 1: Raman spectra of rGO

25th


91

Reinforced Reduced Graphene Oxide Sheets as Materials for EMI Shielding in Ku Band

Shilpa Ua, Saurabh Parmar

b, Bishakha Ray

b and Suwarna Datar

b

aDepartment of Materials Mysore University

bDepartment of Physics, Defence Institute of Advanced Technology


Abstract:

In the age of electronics, disturbance and damage caused due to electromagnetic waves has

become a serious market concern for every frequency band in use. With this issue in mind,

research towards finding exceptional solutions tailor made for specific problems has picked

up speed. We report reduced graphene oxide (rGO) sheets made by a simple process

reduction of graphene oxide (GO) sheets using a solution of hydrochloric acid. The reduction

of GO to rGO was confirmed using Raman and XRD techniques. The sheets showed high

conductivity for an optimized thickness of 0.05mm. These sheets are supported by a resistive

glue spine for increased flexibility. These thin, flexible and conducting sheets were studied

for their electromagnetic shielding [1] properties in the Ku band (12.4-18 GHz). Variations in

concentration of rGO in the sheets gave shielding efficiency ranging from ~15-35 dB. The

shielding observed was majorly due to absorption (> 90%) of the electromagnetic wave,

which makes these sheets good for commercial application.

Reference:

Joshi, Anupama, et al. "Graphene nanoribbon–PVA composite as EMI shielding

material in the X band." Nanotechnology 24.45 (2013): 455705

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92

Reinforced Reduced Graphene Oxide Sheets as Materials for EMI

Shielding in Ku Band

Shilpa Ua, Saurabh Parmar

b, Bishakha Ray

b and Suwarna Datar

b

aDepartment of Materials Mysore University

bDepartment of Physics, Defence Institute of Advanced Technology


Abstract:

In the age of electronics, disturbance and damage caused due to electromagnetic waves has become a

serious market concern for every frequency band in use. With this issue in mind, research towards

finding exceptional solutions tailor made for specific problems has picked up speed. We report

reduced graphene oxide (rGO) sheets made by a simple process reduction of graphene oxide (GO)

sheets using a solution of hydrochloric acid. The reduction of GO to rGO was confirmed using Raman

and XRD techniques. The sheets showed high conductivity for an optimized thickness of 0.05mm.

These sheets are supported by a resistive glue spine for increased flexibility. These thin, flexible and

conducting sheets were studied for their electromagnetic shielding [1] properties in the Ku band (12.4-

18 GHz). Variations in concentration of rGO in the sheets gave shielding efficiency ranging from

~15-35 dB. The shielding observed was majorly due to absorption (> 90%) of the electromagnetic

wave, which makes these sheets good for commercial application.

Reference:

Joshi, Anupama, et al. "Graphene nanoribbon–PVA composite as EMI shielding material in the X

band." Nanotechnology 24.45 (2013): 455705

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93

To study electronic properties of graphene using Density functional theory

as implemented in Quantum Espresso

Vaishnavi Chothe & Shruti Sabale

Project Guide: Dr.P.B.Shelke Sir.

Department of Physics, Ahmednagar College, Ahmednagar-414001, India Presenting author: [email protected]

[email protected]

Abstract:

In this project we have employed QUANTUM ESPRESSO to study the properties of single

layer of graphene using Density Functional Theory (DFT). In this project we have obtained optimized

structure of grapheme. From this we have calculated density of states (DOS), Band structure, and

Phonon calculations. The results of the work are summarized in the following figure.

Figure: Properties of Graphene

References:

1. QUANTUM ESPRESSO manual

2. Solid state Physics by S. O. Pillai

3. An Introduction to Density Functional Theory, by N. M. Harrison

4. http://en.wikipedia.org/wiki/Graphene



http://en.wikipedia.org/wiki/Graphene

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94

0.4 0.2 0.0 -0.2 -0.4 -0.6 -0.8 -1.0 -1.2

1.5

1.0

0.5

0.0

-0.5

-1.0

-1.5

-2.0

-2.5

Voltage (V)

Anodic scan

Cathodic scan

Cu

rren

t d

en

sit

y (m

A/c

m2 )

Scan rate: 5mV/sec

ZnTe

Deposition and Characterization of Zinc Telluride thin film as Interface

Layer for CdTe Solar cells

Shivaji M Sonawane , N B Chaure

Electrochemical Laboratory, Department of Physics, Savitribai Phule Pune University, Pune-411007,

India.


Abstract:

ZnTe thin films have been synthesized using an electrodeposition process from an acidic aqueous

solution by potentiostatic conditions on FTO substrates. The reaction mechanism has been studied by

cyclic voltammetry with scan rate 5 mV sec−1 to identify the deposition potential. ZnTe thin films

electrodeposited at -0.9 V with respect to Ag/AgCl reference electrode. As deposited films are close

to the stoichiometric composition. The band gap energy of ZnTe thin films is observed at 2.25eV by

Vis– UV spectroscopy. X-ray diffraction, Raman spectra as well as SEM techniques have been

employed to investigate the structure and surface morphology of as-deposited films. As deposited

ZnTe layer has cubic structure with (111) preferential orientation. Globular surface morphology was

observed from SEM micrograph. Zn rich layer are grown at growth potential -0.9V.

Figure: Cyclic voltammogram recorded for ZnTe co-deposition in presence of ZnSO4 and

TeO2 in an aqueous bath at pH 2.5 with scan rate 5mV/sec.

Refferences:

Weng Z P ,Ma S S , Wu H Z ; solar energy materials and solar cells, Volume: 179 (2018)Pages: 276-

282

S. Ulicna , C.A.Wolden; Vacuum, Volume-139, (2017) Pages 159-163

Chaure, N B, Chaure S , Pandey R K ; Journal of Materials Science-Materials in electronics, Volume-

28(16) (2017) Pages: 11823-11831


http://apps.webofknowledge.com/DaisyOneClickSearch.do?product=WOS&search_mode=DaisyOneClickSearch&colName=WOS&SID=C5Zlm2vTqkuileQKeWW&author_name=Wu,%20HZ&dais_id=190514&excludeEventConfig=ExcludeIfFromFullRecPage&cacheurlFromRightClick=no

https://www.sciencedirect.com/science/article/pii/S0042207X17300027#!

http://apps.webofknowledge.com/DaisyOneClickSearch.do?product=WOS&search_mode=DaisyOneClickSearch&colName=WOS&SID=C5Zlm2vTqkuileQKeWW&author_name=Chaure,%20NB&dais_id=380369&excludeEventConfig=ExcludeIfFromFullRecPage&cacheurlFromRightClick=no

http://apps.webofknowledge.com/DaisyOneClickSearch.do?product=WOS&search_mode=DaisyOneClickSearch&colName=WOS&SID=C5Zlm2vTqkuileQKeWW&author_name=Chaure,%20S&dais_id=2993574&excludeEventConfig=ExcludeIfFromFullRecPage

http://apps.webofknowledge.com/DaisyOneClickSearch.do?product=WOS&search_mode=DaisyOneClickSearch&colName=WOS&SID=C5Zlm2vTqkuileQKeWW&author_name=Pandey,%20RK&dais_id=9340&excludeEventConfig=ExcludeIfFromFullRecPage

25th


95

Excellent supercapacitive performance of ZnO@MnO2 nanostructures

Mangesh A. Desai, Shrikrishna D. Sartale

Thin Films and Nanomaterials Laboratory, Department of Physics, Savitribai Phule Pune University, Pune- 411 007, India


Abstract:

Manganese oxides have attracted tremendous attention because of their high

theoretical specific capacitance and energy density compared with carbon based materials.

Moreover, they are available in low cost and possess low toxicity which makes them

attractive material for supercapacitor applications. However, their poor electrical conductivity

limits the charge/discharge rate for high-performance supercapacitors and leads to the real

experimental specific capacitance far from their theoretical value. The most excellent solution

to resolve this issue is insertion of a conductive layer of metal oxide like ZnO below the

electrode material to enhance the conductance and surface area. ZnO has ability to mold in

numerous morphologies which lead to generation of large sets of different nanostructures.

Herein, we have synthesized various polymorphs of ZnO nanostructures like nanoflakes and

nanorod. Such morphologies are uniformly decorated by MnO2 nanostructures by using

SILAR method. Prepared composites were characterized by several techniques to understand

their physicochemical properties. Electrochemical studies revealed excellent supercapacitive

performance of ZnO@MnO2 than pristine MnO2 and ZnO nanostructures. Owing to good

chemical stability, effectively high surface area and high conductance, ZnO nanostructures

provide efficient mechanical support and pathway for electron conduction thereby giving

excellent supercapacitive performance.


25th


96

Synthesis and Characterization of PbO nanostructures by Hydrothermal

Method

Anuja S. Gore, Ashwini B. Ambre, V. N. Suryawanshi, Ashwini S. Varpe, M. D. Deshpande

Department of Physics, H. P. T. Arts and R. Y. K. Science College, Nashik, Maharashtra-

422005, India.

Abstract:

PbO nanoparticles are synthesized by hydrothermal method in presence of various solvents -

water, methanol, propanol and butanol. The nanoparticles are synthesized with the variation

of time i.e. 6, 12, 24 and 48 hrs. X- ray diffraction (XRD) and Scanning Electron Microscopy

(SEM) have been used to study the structural and morphological properties of synthesized

PbO nanoparticles while the optical properties have been studied using UV- visible

spectroscopy. Time and solvent dependent band gap variations are observed. Further we have

prepared thick films of nanoparticles by using screen printing for detection of CO2 gas. We

found that structural variation and particle size influences the response of PbO thick films

towards the CO2 gas.

25th


97

Study of Novel SrDy2O4:Eu phosphor for Thermoluminescence Dosimetry

Supriya P. Moholkar, K. H. Gavhane, M. S. Bhadane, V. N. Bhoraskar, S. S. Dahiwale, and

S. D. Dhole

Microtron Accelerator Laboratory, Department of Physics S. P. Pune University, Pune

411007.


Abstract:

Novel SrDy2O4:Eu phosphor was synthesized by solid state diffusion method and annealed at

1350 oC for the radiation dosimetry using thermoluminescence (TL) method. SrDy2O4:Eu

having Zeff ~ 58, therefore it may useful in high dose measurement. The synthesized powder

of SrDy2O4:Eu phosphor, characterized by X-ray diffraction method which shows

orthorhombic structure with 26.42 nm crystallite size. The morphological study of the

SrDy2O4:Eu phosphor were carried out using SEM where the average particle size found

~2.15 µm. The TL intensity of the SrDy2O4:Eu exposed to 1 kGy gamma rays discussed on

the basis of radiation induced trapping levels and annealing process. The peak position of

glow curve is around 205 °C, which is very favourable for SrDy2O4:Eu phosphor to be used

as gamma dosimeter.

References:

1. B.C. Bhatt and M.S. Kulkarni, Thermoluminescent Phosphors for Radiation Dosimetry,

Defect and Diffusion Forum Vol. 347 (2014) pp 179-227

2. Jyoti Singh et.al. Thermoluminescence studies of solid-state reaction derived and γ-

irradiated SrGd2O4: Eu3+ phosphor, Material research Bulletin (2017), S0025-5408

3. Principle of Thermoluminescence, Munish Kumar, BARC Mumbai.

4. Numan Salah and P. D. Sahare, Rad. Effe. Def. Sol. 159 (2004) 321

25th


98

Thermoluminescence studies of Co-60 - ray irradiated BaB4O7:Ce

Akash S. Bhoir, K. H. Gavhane, M. S. Bhadane, V. N. Bhoraskar, S. S. Dahiwale, and S.

D. Dhole

Microtron Accelerator Laboratory, Department of Physics S. P. Pune University, Pune 411007.


Abstract:

Thermoluminescence (TL) or thermally stimulated luminescence (TSL) is the emission of light from a

wide band gap material called phosphor during heating, which has already been exposed to ionizing

radiations (x, β and γ rays). [1]. In this paper, we synthesized BaB4O7:Ce material via solid state

diffusion method. The materials properties of BaB4O7:Ce was studied by XRD, SEM, and TL. To

study the TL properties, powder of BaB4O7:Ce was prepared and subsequently irradiated with Co-60

-rays in the different doses. Structural pattern of XRD indicates that the monoclinic phase with

crystallite size ~ 28 nm. Moreover, the morphological study of phosphor studied by SEM and particle

size is found ~ 2.1 µm. TL measurements BaB4O7:Ce phosphors shows a strong well resolved solitary

peak at 170 °C. In addition, the TL response curve is observed to be linear. Finally, BaB4O7:Ce

phosphor was successfully studied for structural and morphological properties along with

Thermoluminescence properties for dosimetric applications.

References:


2. B.C. Bhatt and M.S. Kulkarni, Thermoluminescent Phosphors for Radiation

Dosimetry, Defect and Diffusion Forum Vol. 347 (2014) pp 179-227

3. Principle of Thermoluminescence, Munish Kumar, BARC Mumbai


25th


99

Synthesis and characterization of Zinc Oxide nanoparticles by Simple

Precipitation method in aqueous media

Gaikwad Mahesh Bapu, Mergal Shivaji Navnath

Department of Physics Ahmednagar college, Ahmednagar, 414001 India.

[email protected]

[email protected]

Abstract:

Present work demonstrates preparation of Zinc Oxide nanoparticles by simple precipitation

method. Prepared nanoparticles has been calcined at various temperatures. The study of

structural and optical properties of prepared nanoparticles has been done corresponding to

calcined and room temperature prepared zinc oxide nanoparticles.UV analysis gave the band

gap corresponding to actual value. XRD analysis demonstrates the prepared nanoparticles has

belonged to Hexagonal Wurtzite crystal structure. Nanoparticle size measured by UV

Absorbance curve and XRD analysis has been matched.

References:

1. Hamid Reza Ghorbani, ’Synthesis of ZnO nanoparticles by Precipitation method’,

Oriental Journal of Chemistry,1219-1221.

2. SatyanarayanTalam, Srinivas Rao Karumuri and Nagarjuna Gunnam, ‘Synthesis,

characterization and spectroscopic properties of ZnO nanoparticles’, ISRN

nanotechnology Vol 2012, 1-6.

3. Surabhi Siva Kumar, PutchaVenkateswarlu, ‘Synthesis, characterization and optical

properties of Zinc Oxide Nanoparticles’ International Nano Letters 2013, 1-6.

4. R. Suganya, N. Krishnaveni, T.S. Senthil’Synthesis and characterization of ZnO

nanocrystals from chemical and biological methods and its photocatalytic activities’,

Int.J. ChemTech Res. 2015 490-496.


25th


100

Study of growth and properties of Pure and CaCO3 doped Triglycine

Sulphate (TGS) crystal by solution growth method

Pratiksha Lande, Kalyani Annadate

Department of Physics , Ahmednagar College, Ahmednagar 414001, India

[email protected]

[email protected]

Abstract-

Stated work consisted of growth of Triglycine Sulphate (TGS) crystal by solution growth

method [1-3]. Study of Pure and CaCO3 doped TGS crystal has done. It has been found that

growth rate corresponding to CaCO3 doped TGS crystal was maximum in comparison with

pure TGS crystals. Doped TGS crystals were more transparent. The refractive index

calculation has done by Real and Apparent depth method signifies that refractive index of

doped TGS crystal was 1.358 and pure TGS crystal was 1.5265. Dielectric constant study

represents there was no change in Curie temperature of doped and TGS crystal. It was found

that dielectric constant increases up to 500c temperature and then it decreases.

References-

[1] R. B. Lal, A.K. Batra, “Growth and properties of triglycine sulfate (TGS) crystals: Review”,

Journal of Ferroelectrics, 51-82, 2011.

[2] R. B. Lal., M. D. Aggarwal, R. L. Kroes, W. R. Wilcox, “A new technique of solution crystal

growth”, Applications and material science, 547-552, 1983.

[3] M. Senthil Pandian, N. Balamurugan, V. Ganesh, P. V. Shekar, “Growth of TGS single crystal by

conventional and SR method and its analysis on the basis of mechanical, thermal, optical and etching

studies”, Material Letters, 3830-3832, 2008.



25th


101

Facile aqueous route for the synthesis of Cu2SnS3 thin films for

Photoelectrochemical solar cell application

Monika P. Joshia, Suvarta. D. Kharade

a, P. N. Bhosale

*a

aMaterials research Laboratory, Department of Chemistry, Shivaji University, Kolhapur-416004,

India.


Abstract:

In the present investigation, we have synthesized ternary Cu2SnS3 (CTS) thin films by

simple, self organized arrested precipitation technique (APT). The synthesized CTS thin

films were characterized for their optical, structural, morphological, compositional and

photoelectrochemical properties. X-ray diffraction (XRD) technique was used to investigate

the crystal structure and crystalline parameters of the as-synthesized CTS thin films. The

XRD pattern confirms the tetragonal crystal structure of CTS with 42 nm crystallite size.

Further, the crystal structure was confirmed by Raman spectra which showed the formation

of tetragonal crystal phase. The optical band gap of the material evaluated from UV-Vis.

Spectroscopy data and was found to be 1.74 eV [1]. The surface morphological analysis

carried out from Scanning electron microscopy (SEM) depicted the nanospherical formation

of CTS. Energy dispersive X-ray spectroscopy (EDS) and X-ray photoelectron spectroscopy

(XPS) confirms the stoichiometric composition of Cu+, Sn

4+ and S

2- in 2:1:3 proportions

respectively [2]. Finally, the J-V characteristic curve demonstrated the photoelectrochemical

cell applicability of CTS thin films.

Figure: SEM micrograph of Cu2SnS3 thin film.

References:

1. Z. Zhang, Y. Fu, C. Zhou, J. Li, and Y. Lai, Solid State Ionics 269, 62 (2015).

2. H. D. Shelke, A. C. Lokhande, V. S. Raut, A. M. Patil, J. H. Kim, and C. D. Lokhande, J. Mater. Sci.

Mater. Electron. 28, 7912 (2017).


25th


102

Use of TiO2 nanotube arrays with sandwich structure on Nickel for

betavoltaic nuclear battery

Amish Parmar, Ambadas B. Phatangare, Sanjay D. Dhole, Shailendra S. Dahiwale and Vasant N.

Bhoraskar

Microtron Accelerator Laboratory, Department of Physics, Savitribai Phule Pune University, Pune–

411007, India

*Presenting author: [email protected]

Abstract:

Vertically oriented nanotubes of TiO2, a wide gap semiconductor, have been used for the

development of a betavoltaic nuclear battery. A sandwich-type metal/TiO2 nanotubes/metal

structure under build-in contact potential difference was used to investigate beta radiation

effect. The sandwiched structure is integrated by immobilized TiO2 arrays on Ti foil with

radioisotope Sr90

planar source on Ni substrate (Ni–Sr90

/TiO2/Ti). Under irradiation with beta

particles of end point energy 0.546 MeV source with activity of 1.6 Ci, the structure

presents open–circuit voltage of 0.237 V and short–circuits current of 0.01 A. The TiO2

nanotube exhibit a great potential for the development of betavoltaic batteries due to its

excellent property for capturing beta particles and transportation of charge carriers. By

connecting a number such betavoltaic nuclear batteries a voltage upto 2 volts can be buildup

with current limit to 0.1 A. The important role played by the sandwich-type

metal/semiconductor/metal structure (Ni–Sr90

/TiO2/Ti) has been observed under a build-in

electrical field through contact potential difference between Ni and Ti. The enhanced

betavoltaic mechanisms of the metal/semiconductor/metal structure and its optimized design

are presented.

Keywords: Nuclear Battery, TiO2 nanotube Arrays, radioisotope.

References:

1. Dmitry V. Bavykin, Jens M. Friedrich, and Frank C. Walsh, Adv. Mater. 2006, 18, 2807–

2824.

2. M.G. Li and J. Zhang, MEMS 2015, Estoril, PORTUGAL, 18 - 22 January, 2015.

3. Q. Zhang, R. Chen1, H. San, G. Liu, and K. Wang, Transducers 2015, Anchorage, Alaska,

USA, June 21-25, 2015.


25th


103

Pressure dependent ferroelectric properties of LaWN3

Bhakti M. Kshirsagar1;2;a, Namrata Jajkhedkar2;b and Vaishali Shah2;c Department of Physics, S. P. Pune University

2Interdisciplinary School of Scienti_c Computing, S. P. Pune University, Pune 411007

[email protected]

[email protected]

[email protected]

Abstract

First principles electronic structure calculations have been performed on nitride perovskite

LaWN3. The generalized gradient approximation exchange corelation correction was used to

calculate the ground state and it indicates that LaWN3 belongs to R3c space group. Our

results show that the nitride perovskite LaWN3 has a large spontaneous polarization of

around 77_C=m2 as compared to rhombohedral PbZrO3 (39_C=m2) [1] also, LaWN3 has a

narrow bandgap of 1.25 eV as compared

to PbZrO3 (2.96 eV). The large spontaneous polarization indicates that LaWN3 could be

good ferrorlectric semiconductor[2][3]. From a device application perspective the pressure

dependent behaviour of ferroelectric materials is of interest. Towards this aim we are

investigating the pressure dependence of piezoelectric constants and polarization in LaWN3.

References

[1] Jaykhedkar Namrata, Vaishali Shah, and S. Premkumar, AIP Conf. Proc. Vol. 1942. No.

1. AIP Publishing, 2018.

[2] Fang, Yue-Wen, et al. Phys. Rev. B 95.1 (2017): 014111.

[3] Krbel, Sabine, Miguel AL Marques, and Silvana Botti, J. Mater. Chem. C 4.15 (2016):

3157-3167.




25th


104

Studies on ethanol electro-oxidation over metal nanoparticles grown using

successive ionic layer adsorption and reaction method

Akshay Vyas and S. D. Sartale*

Thin films and nanomaterials laboratory, Department of Physics, Savitribai Phule Pune University,

Pune – 411 007

[email protected]

Abstract:

Direct ethanol fuel cells (DEFCs) have emerged as the best option to hydrogen fuel

cells to answer the ever increasing energy demands. DEFCs are easier to handle in

comparison to hydrogen fuel cells, thanks to the ease in storage and transportation of ethanol

which is comparatively easier than hydrogen. Ethanol is non-toxic and can be easily produced

using agricultural waste products. By far the best known catalysts are the platinum group

metals, but they are too expensive to be used commercially on a large scale. Non-noble metal

nanoparticles can be useful in terms of partially replacing the platinum group or noble metal

catalysts.

Mainly researchers are focused to develop low cost catalysts which can act as good

anode materials for ethanol electrooxidation reaction. New and competent methodologies are

explored for designing such catalysts. In this study we have grown nickel and palladium

nanoparticles using a comparatively simpler and efficient method namely successive ionic

layer adsorption and reaction (SILAR) and studied its ethanol electrooxidation. We also tried

to prepare nickel-palladium nanoparticles for ethanol electrooxidation reaction. Observations

through cyclic voltammograms suggest that nickel nanoparticles can partially substitute

palladium nanoparticles and significantly affect the overall ethanol electrooxidation activity

than pure palladium nanoparticles.


25th


105

Comparative study of ZnS thin films grown by MA-CBD and M-CBD

methods

Nishigandha Gunjal, Akshay Sonawane

Department of Physics, Ahmednagar College, Ahmednagar 414001, India

[email protected]

[email protected]

Abstract:

In present investigation a comparative study has been carried out on growth of ZnS layer on

to soda lime glass substrate by Microwave assisted chemical bath deposition (MA-CBD) [1]

and Modified chemical bath deposition methods (M-CBD) [2]. ZnS thin layers with 12 and

14 pH were grown on glass substrate. Tolansky technique has been used to determine the

thickness of the ZnS layers [3]. Grown layers were investigated with the help of UV-Vis

spectroscopy. Tauc plot were deployed to obtain the band gap of thin films which is nearly

equal to 3.8 eV. In addition to this refractive index were obtained with the help of UV-Vis

absorbance which is 2.6which is close to reported value.

References:

[1] Mudi Xin, KunWei Li, Hao Wang, “ Synthesis of CuS thin films by microwave assisted

chemical bath deposition” Applied Surface Science, 1436-1442, 2009.

[2]H. M. Pathan, C. D. Lokhande, D.P. Amalnerkar, T. Seth, “Praparation and

characterization of copper telluride thin films by modified chemical bath deposition (M-

CBD) method”, Applied Surface Science, 291-297, 2003.

[3]A Piegari, E Masetti, “Thickness measurement: A comparison of various techniques”,

Thin solid films, 249-257, 1985.



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Studies on the Influence of RF Power on Al doped ZnO Thin Films

Pankaj K. Bhujbal, Habib M. Pathan and Nandu B. Chaure*

Department of Physics, Savitribai Phule Pune University, Pune - 411007, India.


Abstract:

Al:ZnO is one of the promising alternatives for Indium Tin Oxide for conducting transparent

electrode due to its high conductivity, high transparency, natural abundance and low-cost [1]. The

potential applications of transparent conducting electrodes in flat panel displays, photovoltaic cells,

light emitting diodes and semiconductor lasers and sensors [2].

In present study, the Al:ZnO thin films are grown by using the RF magnetron sputtering

technique onto microscopic glass slides and the effect of RF power onto the optical, electrical,

structural and morphological properties were studied using UV-Visible spectroscopy,

Photoluminescence, Hall measurement system, X-ray diffraction (XRD) and Atomic force

microscopy (AFM) respectively. Transparent and highly conducting Al:ZnO thin films were grown

by RF magnetron sputtering technique for various deposition RF powers. XRD spectra revealed that

the film deposited at 200 W have wurtzite crystal structure with (002) preferred orientation [3].

Optical studies confirmed highly transparent films with energy band gap ranging from 3.5 to 3.3 eV

upon changing the deposition powers from 50 -200 W, which is could be due to the growth of large

particles at higher power. They were found be 95 % transparent. Compact, uniform grain growth and

void free surface of the layer was observed from AFM images. The presence of Zn i, VZn, V0 and V0+

defects were found from PL spectra. Hall measurement data revealed that the film deposited at 200W

RF power has minimum resistivity of 4.2 x 10-3

Ωm.

Acknowledgment: Authors are thankful to Department of Science and technology, New Delhi for

financial support under Solar Energy Research Initiative schemes.

References:

1. Rakesh A. Afre, Nallin Sharma, Maheshwar Sharon and Madhuri Sharon, Rev. Adv. Mater.

Sci., 53, 2018, 79-89.

2. Yi-Cheng Lin, Kun-Hsin Lu, Jhih-Jhong Chen, Chinese Journal of Physics, 54, 2016, 475 –

482.

3. Pankaj K. Bhujbal, Habib M. Pathan and Nandu B. Chaure, ES Energy & Environment, 2019.

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TiO2-Carbon Dot composite for Visible Light Photocatalytic Degradation

of Beta Blocker Propranolol Amruta Ponkshe

a, Pragati Thakur*

aDepartment of Environmental Sciences, Savitribai Phule Pune University, Pune, Maharashtra

411007. *Department of Chemistry, Savitribai Phule Pune University, Pune, Maharashtra 411007.

Author: [email protected]

*Corresponding author: [email protected]

Abstract:

Degradation of pharmaceutical wastewater containing recalcitrant pollutants is emerging

problem of today as these ingredients constitute health risk for humans, terrestrial as well as

aquatic organisms. Conventional biological methods have shown to be insufficient for the

removal of all potentially hazardous constituents of the wastewater. Beta blocker Propranolol

(PR) is one of such pollutants which are difficult to degrade through conventional treatment

methods. Many reports are available on degradation of PR in solar light but only few in

visible light source. Traditional photo-catalyst TiO2 cannot make use of visible light that

accounts for 45% of solar spectrum because of its large bandgap (3.2 eV). Strategies such as

metal doping and doping with carbon materials are used to enhance the properties of TiO2. Here an attempt has been made to extend the light absorption of TiO2 in visible light region

by synthesizing Carbon Dots-TiO2 (CD-TiO2) composite where degradation efficiency of

TiO2 is enhanced by carbon dots which works as photosensitizers. Up converted PL behavior

of C Dots helps transfer energy to TiO2 which generates electron-hole pair. Carbon dots were

prepared by Electrophoretic dissolution method and Sol gel method was used to prepare TiO2

and CD-TiO2 composites. Prepared photo catalysts were characterized by XRD, UV-Vis

Spectrophotometer, PL, SEM and FTIR. Quantity of C dots in the composite was optimized

for enhancement of photocatalytic degradation of PR. 5 mL CD-TiO2 have shown 50 %

increase in degradation of PR as compared to bare TiO2.

Figure: a) (XRD pattern of TiO2, C Dot-TiO2 composites and Carbon Dots)

b) (% Degradation of TiO2 and C Dot-TiO2 composites)

References: (a) Clara, M.; Strenn, B.; Gans, O.; Martinez, E.; Kreuzinger, N.; Kroiss, H. Water Res., 39 (19),

(2005) 4797-4807.

(b) Joss, A.; Keller, E.; Alder, A.; Göbel, A.; McArdell, C.; Ternes, T.; Siegrist, H. Water Res., 39

(14), (2005) 3139-3152.

(c) Suman Raj, D.; Anjaneyulu, Y. Process Biochem., 40 (1), (2005) 165-175).

(d) Giri, R. R.; Ozaki, H.; Ota, S.; Takanami, R.; Taniguchi, S. Int. J. Environ. Sci. Tech., 7 (2),

(2010) 251- 260.

(e) Markad G., Kapoor S., Haram S., Thakur P.; Solar Energy, 144 (2017) 127-133.



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Synthesis and characterization of graphene based hybrids for nonvolatile

memory devices such as RRAM

Chaitali Pawasea, Dhananjay Bodas

c, and Suresh Gosavi

a b

aDeparment of Electronic Science, SPPU, Ganeshkhind, Pune-411007, India.

bDepartment of Physics, SPPU, Ganeshkhind, Pune -411007, India.

cNanobioscience Group, Agharkar Research Institute, Pune-411004,India.


Abstract:

In this work, we discuss the GO‐ based nanocomposites for RRAM devices, which have been

strong demand for novel nonvolatile memory technology for low-cost, large-area, and low-power

flexible electronics applications. Hence, we have synthesized GO/RGO/RGO-ZnO nanocomposite for

nonvolatile memory devices. Graphene oxide (GO) and reduced graphene oxide (RGO) have been

synthesized by modified Hummer’s method. The cost-effective hydrothermal method were employed

to prepare reduced graphene /zinc oxide (RGO/ZnO) Nano composite using zinc

acetate((CH3COO)2Zn·2H2O) precursor. For the structural, morphological and elemental analysis, the

synthesized samples were characterized by X-ray diffraction (XRD), Scanning electron microscopy

(SEM), UV-VIS spectroscopy, FTIR spectroscopy and Raman spectroscopy. X-ray diffraction pattern

was recorded for GO, RGO and RGO/ZnO nano composite and their respective diffraction patterns.

The UV-VIS spectroscopy shows the lambda max at 230 nm and Raman spectroscopy shows 0.78

ID/IG ratio. Morphological analysis of SEM reveals good coverage of composite material on GO and

RGO. The carbon based nanostructure materials such as GO/RGO/RGO-ZnO were successfully

synthesized and characterized. As ZnO hybrids are showing electrochemical behavior we can claim

that it has resistive switching property. In addition, we found that the synthesized ZnO–RGO

composites exhibited improved electrochemical stability. Such ZnO–RGO hybrid materials represent

promising electrochemical sensors with high sensitivity and selectivity, improved stability, and fast

amperometric response. Hence we can do further research for development of resistive nonvolatile

memory using Graphene based nanocomposites.

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Structural Ferroelectric and Dielectric properties of lead free

Ba0.97Ca0.03TiO3 electroceramic

Tulshidas C. Darvade, B. G. Baraskar, P. S. Kadhane, O. A. Ramdasi and Rahul C.

Kambale

Department of Physics, Savitribai Phule Pune University, Pune -411007,

Presenting author: [email protected],

Abstract:

Lead- free Ba0.97Ca0.03TiO3 (BCT) ceramic was synthesized by the solid state reaction route. Their

structure and electrical were analyzed. The obtained XRD pattern of Ba0.97Ca0.03TiO3 showed that

synthesized ceramic crystallized in the tetragonal phase at room temperature and all observed

intensity well matched with Bragg positions. Microstructure analysis of synthesized Ba0.97Ca0.03TiO3

was carried out with scanning electron microscopy which showed the pyramid like microstructure as

shown in Fig. 1. The frequency - temperature dependence permittivity study of Ba0.97Ca0.03TiO3

showed the phase transition from the tetragonal to cubic phase at Tc ~148 oC and dielectric constant

r~4650. The observed Curie temperature for Ba0.97Ca0.03TiO3 is higher than that of pure BaTiO3.

Temperature dependent P-E hysteresis loop shows the stable P-E hysteresis loop from room

temperature to 140 oC. Planer electromechanical coupling factor is kp ~ 0.22 calculated from the

antiresonance (fa = 318200 Hz) and resonance (fr = 311600 Hz) frequencies of polled Ba0.97Ca0.03TiO3

at 500 V at room temperature for 30 minutes.

Figure 1. Shows SEM image of Ba0.97Ca0.03TiO3.


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Synthesis and Characterization of CeO2 nanostructures for the catalytic

degradation of methylene blue

Sandhya Gadgea, Ashif H. Tamboli

a, Kiran P. Adhi

a, Suresh W Gosavi

a*,

aDepartment of Physics, Savitribai Phule Pune University (Formerly University of Pune), Pune 411

007, India.

*Corresponding author. Tel.: Phone: +91-20-25692678, Fax: +91-20-25691684

E-mail address: [email protected]

Abstract

This present work reports a study about the adsorption of methylene blue (MB) by

synthesized CeO2 nanostructure. The characterization techniques like scanning electron

microscopy (SEM), transmission electron microscopy (TEM), Raman spectroscopy and

Fourier Transform Infrared spectroscopy (FTIR) were employed to examine the morphology,

crystal structure and physico-chemical properties of as prepared material. Furthermore, the

catalytic activity of as prepared CeO2 nanostructured was tested towards degradation of

Methylene Blue (MB) dye. The study reveals that CeO2 spindles can be excellent catalyst for

dye degradation and water purification applications owing to their excellent surface

properties and novel morphology.

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Synthesis and Characterization Graphene based Metal oxidenanocomposite

for Energy Storage Application SarikaJadhav, RamchandraKalubarme,V.P.Godbole,B.B.Kale, S.W.Gosavi

Department of Physics, University of Pune, Pune-411007

Centre for Materials for Electronic Technology, Panchawati, Off. Pashan Road, Pune –

411008

Presenting author:[email protected].

Abstract:

Transition metal oxides with multiple reversible oxidation states are normally considered as

potential active materials for supercapacitors. The composite of graphene with

MnO2nanorods is obtained through simple hydrothermal oxidation of the Mn-precursor on a

graphene surface and tested as electrode material in supercapacitor devices. In

microstructural exploration, a fine distribution of MnO2nanorods over the entire graphene

surface is evinced from transmission electron micrograph. The nanocomposite demonstrated

noticeable charge storage activity with small diffusion resistance. The galvanostatic charge-

discharge performance of the composite electrode in a symmetric and asymmetric device

formation displayed a high energy density of 26 Wh kg-1 corresponding to a specific

capacitance of 436 F g-1. These composite electrodes also demonstrated a long cycle life

with better capacity retention. The excellent capacitive features for supercapacitor devices are

attributed to the MnO2/graphene composite structure, which not only provides the passage for

the electrons but also increases the ion transportation during fast charge–discharge reaction.

Figure (a) TEM image of MnO2-rGOnanocomposite (b) CD of MnO2-rGOnanocomposite


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Synthesis and Field Emission Study of MoO3(Molybdenum Trioxide)

Nanostructures

Kalyani Tikotea, M.A. More

b, N.B. Chaure

c

Field Emission Microscopy Laboratory, Department of Physics, S. P. University of Pune, Pune

411007, India


Abstract:

MoO3 nanostructures were synthesized by simple one step hydrothermal method. For synthesis of

MoO3 nanostructures, 1g of ammonium molybdate ((NH4)6Mo7O24,), and 2g of sodium salicylate

(C7H5NaO3) powders were dissolved in 40 ml double distilled water, stirred for 15 min. The prepared

solution was transferred into a Teflon autoclave (100 ml capacity) and reaction performed at different

temperatures 80, 100, and 120 °C for 12 h. The resultant white precipitates were filtrated and washed

several times with distilled water and ethanol. As- obtained products were annealed in furnace at

350°c for 1 h in the ambient. The morphological and structural characterization of the as-synthesized

product was carried out by using scanning electron microscopy (SEM), transmission electron

microscopy (TEM) and X-ray diffraction spectroscopy (XRD). The Field Emission (FE) behaviour of

synthesized MoO3 nanorods was investigated. The turn-on field required to draw an emission current

density of 1 μA/cm2 found to be 6.5 V/μm for MoO3. Furthermore, maximum emission current density

of ~ 587 µA/cm2 was drawn at an applied field of 12 V/μm. Furthermore, the MoO3 emitter exhibits

good emission current stability at the preset value of 5 µA. The observed FE characteristics of the

MoO3 nanorods emitter are attributed to the high aspect ratio and good electrical property.

References:

1. Bin Yan, Zhe Zheng, Hao Gong, Zexiang Shen ; J.phys.chem.c,113 (2012) 02259-20263.

2. Y.B.Li, Y.Bando, K.Kurashima ; phys.Lett.81 (2002) 5048.

3. DongmeiBan, ShaozhiDeng,NingshengXu, JunChen,JuncongShe, andFeiLiu, Journal of Nanomaterials

Volume 2010, Article ID 136860.

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Synthesis and Size Control of Silver Nanoparticles using Low Energy Ar-

Ion Irradiation

Mayuri T. Jagdale, Ashish B. Thorat, Shailendra S. Dahiwale, Sanjay D. Dhole and Vasant N.

Bhoraskar

Microtron Accelerator Laboratory, Department of Physics, Savitribai Phule Pune University, Pune-

411007, India


Abstract: Silver nanoparticles were synthesized using low energy Ar-ion irradiation method. The

Silver Nitrate (AgNO3) solution was drop casted on poly-vinyl alcohol (PVA) thin film and allowed

to dry at room temperature. These drop casted films was then irradiated by Argon ions at energies 10

keV, 20 keV 30 keV and 40keV at room temperature (27-30 0C) in vacuum. During irradiation the ion

current (40uA) and fluence was kept constant. Then samples were characterized by the UV-visible

spectroscopy. The plasmon absorption peaks were observed at 445 nm, 426 nm, 423 nm for 10 keV,

20 keV, 30 keV Ar-ion energies, respectively. However the peak was absent for 40 keV irradiated

samples. The Plasmon absorption peak with ion irradiation confirms the formation of Ag particles due

to the ion irradiation. The result also reveals that with increase in the ion energy particle size of silver

nanoparticles were reduced. The absence of peak at 40 keV irradiated sample may be due the

sputtering process, which could be dominantly happened at this energy for our samples. Further

analysis is in the process.

References:

(i) KABogle, et al 2006 Nanotechnology17 3204–320.

(ii) Porel S, et al 2005 Chem. Mater. 17 9

(iii) Temgire M K et al 2004 Radiat. Phys. Chem. 71 1039

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Excellent supercapacitive performance of marigold like nanostructures of

Manganese dioxide

Aditi R. Kulkarni, Mangesh A. Desai, and S. D. Sartale.

Thin films and nanomaterials laboratory ,

Department of Physics, SavitribaiPhule Pune University, Pune, 411007.


Abstract:

For supercapacitor application transition metal oxides are considered as best alternatives over the

other electrode material due to theirhigh power density. Among all transition materials Manganese

dioxide (MnO2) stands out from other due its abundance, non-toxicity, environmental friendly,

structural flexibility and its high theoretical specific capacitance. MnO2charge storage mechanism

consist of major processes like surface adsorption of electrolyte ions, redox between Mn3+

/Mn4+

and

intercalation/de-intercalation of cations from electrolyte solution.

Herein we have used simple, cost effective and efficient deposition method known as Successive

Ionic Layer Adsorption and Reaction (SILAR) to synthesize MnO2marigold nanostructures. Most

importantly, we have deposited MnO2 thin films over three dimensional substrate of stainless steel

mesh. The facile way of synthesis was carried out at room temperature by using precursors

likestrongoxidizing agent (KMnO4) and mild reducing agent (MnSO4). The capacitive performance of

prepared thin films was characterized by cyclic voltammetry (CV) and galvanostatic charge/

discharge (GCD). The prepared thin films show excellent supercapacitive performance due to its three

dimensional structure and surface area.


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Figure 1.Phonon Dispersion Curve of Cu2ZnSnS4

Inelastic Neutron Scattering and Lattice Dynamics of Cu2ZnSnS4

S. P. Kandarea, Mala N. Rao

b *, S. S. Dahiwale

a, Rekha Rao

b, and S.L. Chaplot

b

aDepartment of Physics, Savitribai Phule Pune University, Pune, India, 411007.

bSolid State Physics Division, Bhabha Atomic Research Centre, Trombay, Mumbai,India,400085.

[email protected]

Abstract:

Kesterite structure Cu2ZnSnS4 belonging to I2-II-IV-VI4 chalcogenide quaternary group is a

compound used in photovoltaic applications. We report inelastic neutron scattering measurements on

Cu2ZnSnS4 synthesized by microwave assist method [1, 2], carried out on triple- axis spectrometer at

Dhruva reactor. These are compared with computations of the phonon density of states. These studies

elucidate the understanding of the vibrational spectrum, leading to the thermal properties. All the

measurements are carried out in the energy loss mode with constant momentum transfer (Q).Lattice

dynamics computations were carried out to determine the phonon frequencies in the entire Brillouin

zone. With the number of atoms in the primitive cell being 8, the number of phonon branches along

each direction is 24.

We have computed the phonon dispersion curves of Cu2ZnSnS4 compound; Fig. 1 shows these along

the direction [100]. Also shown in Fig. 1 is the comparison from Raman scattering measurements (at

the point). The calculated optic branches near the zone centre match well with results from Raman

spectroscopy [3]. The energy range of the acoustic modes is up to 100 cm-1

. The optic modes above

300 cm-1

show a large dispersion, whereas those below 300 cm-1

are almost flat.

Figure 2 shows the results of inelastic neutron scattering measurements on Cu2ZnSnS4 up to an energy

transfer range of 30 meV. The experimental data compares well with the computed spectrum. The

effectiveness of a thermoelectric material is represented by the dimensionless figure of merit

ZT=S2T

-1

-1, where S is the Seebeck coefficient, T is the absolute temperature, is the electrical

resistivity, and is the thermal conductivity [4]. For the purpose of the calculation of ZT, the

temperature dependences of , S are taken from Ref. [5]. The computed temperature dependence of

the lattice thermal conductivity lat is shown in Fig. 3. lat decreases in the temperature range 300-700

K, and due to this, ZT increases with increasing temperature, as shown in Fig. 4.

In conclusion, a lattice dynamical model for Cu2ZnSnS4 has been validated through comparison with

experimental measurement of the phonon density of states as well as the other thermoelectric

properties like thermal conductivity and figure of merit.

Figure 2.Experimental (up to 30 meV) and

computed neutron weighted phonon density of

states of Cu2ZnSnS4

0 10 20 30 40 50 600.000

0.002

0.004

0.006

0.008

0.010

g(n

) (E)m

eV

-1

E (meV)

Computed

Experimental

0.0 0.5 1.00

50

100

150

200

250

300

350

400 Raman data [ours]

Raman data [3]

q[100]

Wav

enum

ber

(cm

-1)

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References:

1. S. P. Kandare, A. B. Thorat, S. D. Dhole and S. S. Dahiwale, Indian Jour. of Pure and App. Physics,

57(2019), 7-13.

2. S. P. Kandare, S. D. Dhole, V. N. Bhoraskar and S. S. Dahiwale, AIP Proceedings, 1731(2016)

050084.

3. D. Dumcenco and Y S Huang, Optical Materials, 35 (2013) 419.

4. L. Choubrac, A. Lafond, C. G. Deudon, Y. Moelo, and S. Jobic , Inorg. Chem. 51 (2012) 3346.

5. H. Yang, L.A. Jauregui, G. Zhang, Y. P. Chen and Y. Wu, Nanoletters 12 (2012) 540.

Figure 3. Temperature dependence of lattice

thermal conductivityof Cu2ZnSnS4. Experimental

data is from [4].

300 400 500 600 7000.5

1.0

1.5

2.0

2.5

3.0

3.5

lat(W

/m-K

)

Temperature (K)

Computed

Experimental

Figure 4. Temperature dependence of the figure

of merit of Cu2ZnSnS4. Experimental data is

from [4].

300 400 500 600 700

0.000

0.005

0.010

0.015

0.020

0.025

0.030

Cu2ZnSnS

4

ZT

Temperature (K)

computed

experimental

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Abstract Book - physics.unipune.ac.inphysics.unipune.ac.in/~rmc/2019/RMC2019_Abstract_book.pdf · PP-6 Pooja Galande Study of Cu2O Thin Film Synthesis by Electrochemical Deposition