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Title: Determining ideal strength and failure mechanism of thermoelectric CuInTe 2 through quantum mechanics
CuInTe 2 is recognized as a promising thermoelectric material in the moderate temperature range, but its mechanical properties important for engineering applications remain unexplored so far. Herein, we applied quantum mechanics (QM) to investigate such intrinsic mechanical properties such as ideal strength and failure mechanism along with pure shear, uniaxial tension, and biaxial shear deformations. We found that the ideal shear strength of CuInTe 2 is 2.43 GPa along the (221)[11−1] slip system, which is much lower than its ideal tensile strength of 4.88 GPa along [1−10] in tension, suggesting that slipping along (221)[11−1] is the most likely activated failure mode under pressure. Shear induced failure of CuInTe 2 arises from softening and breakage of the covalent In–Te bond. However, tensile failure arises from breakage of the Cu–Te bond. Under biaxial shear load, compression leads to shrinking of the In–Te bond and consequent buckling of the In–Te hexagonal framework. We also found that the ideal strength of CuInTe 2 is relatively low among important thermoelectric materials, indicating that it is necessary to enhance the mechanical properties for commercial applications of CuInTe 2 .  more » « less
Award ID(s):
1727428
PAR ID:
10062473
Author(s) / Creator(s):
; ; ; ; ; ; ;
Date Published:
Journal Name:
Journal of Materials Chemistry A
Volume:
6
Issue:
25
ISSN:
2050-7488
Page Range / eLocation ID:
11743 to 11750
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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