Computational and experimental investigation of TmAgTe 2 and XYZ 2 compounds, a new group of thermoelectric materials identified by first-principles high-throughput screening

Computational and experimental investigation of TmAgTe 2 and XYZ 2 compounds, a new group of thermoelectric materials identified by first-principles high-throughput screening

TitleComputational and experimental investigation of TmAgTe 2 and XYZ 2 compounds, a new group of thermoelectric materials identified by first-principles high-throughput screening
Publication TypeJournal Article
Year of Publication2015
AuthorsHong Zhu, Geoffroy Hautier, Umut Aydemir, Zachary M Gibbs, Guodong Li, Saurabh Bajaj, Jan-Hendrik Pöhls, Danny Broberg, Wei Chen, Anubhav Jain, Mary Anne White, Mark D Asta, G. Jeffrey Snyder, Kristin A Persson, Gerbrand Ceder
JournalJournal of Materials Chemistry C
Volume3
Issue40
Pagination10554 - 10565
Date Published11/2015
ISSN2050-7526
Abstract

A new group of thermoelectric materials, trigonal and tetragonal XYZ2 (X, Y: rare earth or transition metals, Z: group VI elements), the prototype of which is TmAgTe2, is identified by means of high-throughput computational screening and experiment. Based on density functional theory calculations, this group of materials is predicted to attain high zT (i.e. B1.8 for p-type trigonal TmAgTe2 at 600 K). Among approximately 500 chemical variants of XYZ2 explored, many candidates with good stability and favorable electronic band structures (with high band degeneracy leading to high power factor) are presented. Trigonal TmAgTe2 has been synthesized and exhibits an extremely low measured thermal conductivity of 0.2–0.3 W m1 K1 for T 4 600 K. The zT value achieved thus far for p-type trigonal TmAgTe2 is approximately 0.35, and is limited by a low hole concentration (B1017 cm3 at room temperature). Defect calculations indicate that TmAg antisite defects are very likely to form and act as hole killers. Further defect engineering to reduce such XY antisites is deemed important to optimize the zT value of the p-type TmAgTe2

DOI10.1039/C5TC01440A
Short TitleJ. Mater. Chem. C
Refereed DesignationRefereed