Mechanical properties of thermoelectric lanthanum telluride from quantum mechanics
Abstract
Lanthanum telluride (La_3Te_4) is an n-type high-performance thermoelectric material in the high temperature range, but its mechanical properties remain unknown. Since we want robust mechanical properties for their integration into industrial applications, we report here quantum mechanics (QM) simulations to determine the ideal strength and deformation mechanisms of La_3Te_4 under pure shear deformations. Among all plausible shear deformation paths, we find that shearing along the (0 0 1)/〈100〉 slip system has the lowest ideal shear strength of 0.99 GPa, making it the most likely slip system to be activated under pressure. We find that the long range La–Te ionic interactions play the predominant role in resisting shear deformation. To enhance the mechanical strength, we suggest improving the long ionic La–Te bond stiffness to strengthen the ionic La–Te framework in La_3Te_4 by a defect-engineering strategy, such as partial substitution of La by Ce or Pr having isotypic crystal structures. This work provides the fundamental information to understand the intrinsic mechanics of La_3Te_4.
Additional Information
© 2017 IOP Publishing Ltd. Received 26 March 2017, revised 18 May 2017; Accepted for publication 31 May 2017; Published 19 June 2017. This work is partially supported by National Basic Research Program of China (973-program) under Project no. 2013CB632505, the 111 Project of China under Project no. B07040, Materials Project by Department of Energy Basic Energy Sciences Program under Grant No. EDCBEE, DOE Contract DE-AC02-05CH11231, and China Postdoctoral Science Foundation (408-32200031). We would like to acknowledge the Jet Propulsion Laboratory, California Institute of Technology, as a funding source under a contract with the National Aeronautics and Space Administration, which was supported by the NASA Science Missions Directorate's Radioisotope Power Systems Technology Advancement Program. Computations were carried out on computer clusters provided by a DURIP grant.Additional details
- Eprint ID
- 78328
- DOI
- 10.1088/1361-6463/aa7625
- Resolver ID
- CaltechAUTHORS:20170619-101554499
- 2013CB632505
- National Basic Research Program of China
- B07040
- 111 Project of China
- DE-AC02-05CH11231
- Department of Energy (DOE)
- 408-32200031
- China Postdoctoral Science Foundation
- NASA/JPL/Caltech
- Army Research Office (ARO)
- Created
-
2017-06-19Created from EPrint's datestamp field
- Updated
-
2022-07-12Created from EPrint's last_modified field
- Other Numbering System Name
- WAG
- Other Numbering System Identifier
- 1228