Doctoral Thesis Defence in Physics and Nanoscience18-07-2017

Praveen PattathilCycle : XXIX

Academic year : 2014 – 2017

Coordinator: Prof. Rosaria Rinaldi Supervisors: Dr. Michele Manca

Dr. Carlo Giansante

“Transparent Conductive Oxides Nanocrystals for Energetically

Self-Consistent Dynamic Windows”

OUTLINE

Introduction: Plasmonic Transparent Conductive Oxides (TCO) and

Application

Chapter 2ITO Nanocrystal Plasmonic Electrochromic Window for Near infrared light

modulation

Chapter 3 High aspect-ratio 1D Tungsten Oxide Nanorod Plasmonic

Electrochromic Windows for Visible and Near infrared modulation.

Conclusion

Chapter 1

• Doped Semiconductors: ITO, IZO, FTO

• Transition Metal Oxides: ZnO, SnO, WO3

Chapter 1. Introduction

High Visible Transparency (e.g > 3.1 eV)

High Electrical Conductivity (10-3 Ωcm)

Burstein Moss shift

Transparent Conductive Oxide (TCO) Materials

TCO - Applications

• Touch panel

• Solar Cells

• F. P. Display

• Flexible electronics

Optical band gap widening effect

Plasmon Resonance in Colloidal TCO Nanocrystals

𝜔𝑝 =𝑛𝑒2

𝜀0𝑚0

𝜔𝐿𝑆𝑃𝑅

=𝜔𝑝2

1 + 2𝜀𝑚− 𝛾2

Plasmon frequency tunability in TCO NCs

S. Lounis et al, J. Phys. Chem. Lett 5, (2014): 1564-1574.S. C. Warren et al Langmuir, 2012, 28 (24), pp 9093–9102

Dynamic Windows : Critical Need

Plasmonic Electrochromic Smart Windows: Controlling Visible Light and Heat

WARM COOL DARK

Working Principle

𝜔𝑝 =𝑛𝑒2

𝜀0𝑚0𝜔

𝐿𝑆𝑃𝑅𝛼

Optical properties of ITO NC films during electrochemical modulation.

ITO-NCs electrode - 500nm thick

1M LiClO4 in Propylenecarbonate

DTmax 53% at 2000 nm

Experimental Design

NC’s Synthesis Thin Film & Device Fabrication

Morphological, Optical and Electrochemical CharaterizationPhase : 1

Optimized EC Device

Phase : 2Optimized EC

DeviceDSSC

Solar Powered EC Dynamic Windows

Phase : 3

Chapter 2: Self-powered NIR-selective dynamic windows based on broad tuning of the

LSPRs in mesoporous ITO electrodes

Mesoporous ITO-NCs Electrode preparation and Device Fabrication

Glass

Electrolyte

Glass

Conductive layer

Pt

ITO mesoporous film

Conductive layer

Lab scale Prototype

• Colloidal ITO NCs of variable size and composition

• Film deposition by screen printing (t =500-1000nm)

• Stripping of the hydrophobic capping layer

• High surface area & easy penetration of the

electrolyte

Colloidal Synthesis of ITO NC ITO NCs Viscous Paste As Deposited NCs Film Thermally Annealed NCs Film

@ 3500 C

Visibly Transparent Thin Film

As deposited film

Annealed Filed

As deposited film

Annealed film

Material and Optical Characterisation

TE

MX

RD

SE

M

Transmission and absorption spectra of an ITO-NCs electrode interfaced with DMPII (a,d), LiI (b, e) and LiClO4 (c,f)

Dynamic modulation of LSPR in ITO-NCs

LiI

Electrochemical Measurements

Cyclic voltammograms

Nyquist plots of ITO/EL/Pt EC cells

Time-responsivity at λLSPRmax; potential: ± 1.4 V

C.E of ITO-NC electrodes in different ELs

Table I. Summary of the most meaningful electrochemical and optical figures experimentally detected on six different ELs

EL CDL@1.4V [mF/cm2] JFar @ 1.4V [mA/cm2] ΔTmax

CE

[cm2/C]

tc/tb

[s]

pure solvent / / 8.6% @ 2150 nm -- --

LiI 1M 8.0 96 61.3% @ 1740 nm 222 3/6

DMPII 0.2 M 3.1 66 40.8% @ 1610 nm 145 4/7

DMPII 1M 5.1 111 52.6% @ 1770 nm 187 3/7

DMPII 1M + I2 0.005M 4.8 418 60.8% @ 1800 nm 157 2/5

LiClO4 1M 5.3 / 81.4% @ 2040 nm 1270 82/34

Transmittance Spectra and J-V Curves of SOLAR POWERED NIR EC DEVICE

High maximum transmittance modulation as 73% at 2000 nm @ 1 Sun Transmission spectra J-V curves of three series-

connected DSCs P. Pattathil, R.Giannuzzi, M. Manca. Nano Energy. 30 (2016) 242-251.

Chpater 3: Near-Infrared Selective Dynamic Windows Controlled by Charge

Transfer Impedance at the Counter Electrode

@ 3

60

0 C

-ai

r

Met

hodolo

gy

Electroly

te

Composition

#1 1M LiClO4 in PC/AcN (70/30)

#2 1M LiClO4 + 0.005M LiI in PC/AcN

(70/30)

#3 0.7M LiClO4 + 0.3M LiI in PC/AcN

(70/30)

Mat

eria

l an

d O

pti

cal

Char

acte

risa

tion

Lab scale Prototype

WARM COOL_Single Band DARK_Dual Band

WO3-NR-based EC

∆TMAX

CE @ 1000

nm

[cm2/C]

MAX

∆TLUM

MAX

∆TSOL

MAX

TLUM /TSOL

MAX

∆TNIR

74.1%

at 1500 nm

160

at 1500 nm

17.7 % 38.6 % 1.68 85.1 %

Warm Cool

Optical Properties

SUN

LIGH

T INTE

NSITY

“cool” “dark”CoolDark

∆TMAX

CE @ 1000

nm

[cm2/C]

MAX

∆TLUM

MAX

∆TSOL

MAX

TLUM /TSOL

MAX

∆TNIR

80.1%

at 1500 nm

127

at 1500 nm

66.4 % 61.0 % 1.96 99.8 %

Electrochemical Measurements

i(V)=k1v+k2v1/2

Cyclic voltammograms Nyquist plots of WO3/EL/Pt EC cells

Surface capacitance vs Diffusion currents Variation of the solar irradiance transmitted

across the three EC devices

P. Praveen, et al. Nanoscale 8.48 (2016): 20056-20065

CONCLUSION

• This study demonstrates two modes of electrochromism (EC) such as plasmonic (at near

infrared region) and polaronic (at visible region) in colloidal ITO and 1D WO3 NCs

mesoporous electrodes.

• ITO mesoporous electrode dynamically filter out the NIR radiation: 38% at 780 - 2400

nm and 35.0% by solar powered plasmonic window under 1 sun illumination .

• The tungsten oxide NRs showed an outstandingly wide modulation of the NIR solar

transmittance 99.0 % at 780-1500 nm and VIS 66.4 % at 350 -750 nm.

• The experimental achievements presented here have the potential for next generation of

dynamic glazed building facades, which are prospected to maximize both thermal and

visual comfort at any climatic condition while reducing the overall energy use and

environmental impact.

1. P. Pattathil, R. Scarfiello, R. Giannuzzi, G. Veramonti, T. Sibillano, A. Qualtieri, C. Giannini, P.D. Cozzoli and M. Manca, Near-

infrared selective dynamic windows controlled by charge transfer impedance at the counter electrode, Nanoscale. 48 (2016)

20056-20065.

2. P. Pattathil, R. Giannuzzi and M. Manca, Self-powered NIR-selective dynamic windows based on broad tuning of the localized

surface plasmon resonance in mesoporous ITO electrodes, Nano Energy 30 (2016) 242-251.

3. R. Giannuzzi, M. Balandeh, A. Mezzetti, L. Meda, P. Pattathil, G. Gigli, F. Di Fonzo and Michele Manca, On the Li Intercalation

Kinetics in Tree‐like WO3 Electrodes and Their Implementation in Fast Switchable Electrochromic Devices, Adv. Opt. Mater. 11

(2015) 1614-1622.

4. A. Paravannoor, S.V. Nair, P. Pattathil, M. Manca and A. Balakrishnan, High voltage supercapacitors based on carbon-grafted

NiO nanowires interfaced with an aprotic ionic liquid, Chem. Commun. 28 (2015) 6092-6095.

List of Publications

1. Mara Serrapede, Praveen Pattathil, Roberto Giannuzzi, Mehrdad Balandeh, Luisa De Marco, Simone Valente, Giuseppe Gigli, Fabio Di

Fonzo, Michele Manca, “Smart modulation of the optical transmittance in dye-sensitized photovoltachromic devices” International

Conference on Photovoltaics: new frontiers and applications 16 -18 October 2014, Lecce, Italy.

2. Praveen Pattathil, Riccardo Scarfiello, Roberto Giannuzzi, Giulia Veramonti, Davide P. Cozzoli and Michele Manca “From Capacitance-

controlled to Diffusion-controlled Electrochromism in Shape-Tailored 1D Tungsten Oxide Nanocrystals” 12th International Meeting on

Electrochromism (IME-12), August 28th to September 01, 2016, Delft University of Technology, Delft, Netherlands.

3. Attended the 2nd International Workshop on Technologies for “Optogenetics” during 16th –17th, December,2015 at Lecce, Italy.

4. Attended International Workshop on “Electrochemistry” held on 16-18 September, 2015 at Electrochemistry Department , University of

Bologna, Italy

Attended Conference, Poster Presentation and Workshops

DYE SOLAR GROUP @ IIT-CBN