0 10 20 30 40 50 60

12.9K

13.2K

FC

ZFC

H=10 OeSu

sc

ep

tib

ility

(

ab

r. u

nit

)

T (K)

A new synthesis technique is developed to prepare LiFeAs superconductor at room temperature by using an electrochemical approach which differs from the traditional solid-state reaction at high temperature. Under the electrochemical drive, lithium ions in the solution are inserted into FeAs lattice to directly form LiFeAs on the surface of FeAs substrate at room temperature. The characterization of resulting LiFeAs samples indicate superconducting transition temperature at about 13 K, which is consistent with the reported results. This electrochemical technique offers a promising approach to prepare LiFeAs superconductors as well as thin films. (J. Appl. Phys. 2010)

Main difficulties on synthesis of LiFeAs: (1) LiFeAs is sensitive to moisture and reacts with oxygen and nitrogen. (2) The toxic As-contained compounds should be sealed. (3) The preparation of thin films has not been achieved.

Synthesis of LiFeAs Superconductor at Room TemperatureYang Li, University of Puerto Rico at Mayaguez, DMR 0821284

The motif of synthesis of LiFeAs by inserting Li atoms into FeAs lattice.

Susceptibility of the anode film of LiFeAs (TC 13 K) under initial charging in both ZFC and FC procedure.

FeAs with acetylene black, binder and N-methyl-pyrrolidone were mixed and ground into a jelly

FeAs with acetylene black, binder and N-methyl-pyrrolidone were mixed and ground into a jelly

Painting the jelly onto a clean copper foil(FeAs/Cu-electrode)

Painting the jelly onto a clean copper foil(FeAs/Cu-electrode)

Dried at 60 until N-methyl-pyrrolidone completely evaporated℃Dried at 60 until N-methyl-pyrrolidone completely evaporated℃

Densify FeAs on the surface of copper foil by pressingthen dried in vacuum oven at 120 for 2 hours℃

Densify FeAs on the surface of copper foil by pressingthen dried in vacuum oven at 120 for 2 hours℃

After it cooled down to room temperature, punched the electrode into a certain shape After it cooled down to room temperature,

punched the electrode into a certain shape

The process of preparing the FeAs electrode

The PPMS generates a broader impact on education of pre-college students and their

teachers in underserved Puerto Rico areas.

New materials investigated by using Cryogen-free

Physical Property Measurement System (PPMS) Yang Li, University of Puerto Rico at Mayaguez, DMR 0821284

Pre-existing courses and new developed courses immediately benefit from the instrument.

This instrument immediately support the interdisciplinary research and materials science and engineering training for over 20 undergrads, 20 graduate students, 2 postdoctoral researchers and 7 faculty.

Education activities aim to increase and enhance the education and participation of Hispanics, especially undergraduate and graduate students attending the UPRM.

Research activities requiring PPMS are intimately linked with teaching at UPRM.

Approximately 15% of the instrument operating time is dedicated to education and training.