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Title: Investigating the Role of Vacancies on the Thermoelectric Properties of EuCuSb‐Eu 2 ZnSb 2 Alloys
Abstract AMXcompounds with the ZrBeSi structure tolerate a vacancy concentration of up to 50 % on theM‐site in the planarMX‐layers. Here, we investigate the impact of vacancies on the thermal and electronic properties across the full EuCu1−xZn0.5xSb solid solution. The transition from a fully‐occupied honeycomb layer (EuCuSb) to one with a quarter of the atoms missing (EuZn0.5Sb) leads to non‐linear bond expansion in the honeycomb layer, increasing atomic displacement parameters on theMand Sb‐sites, and significant lattice softening. This, combined with a rapid increase in point defect scattering, causes the lattice thermal conductivity to decrease from 3 to 0.5 W mK−1at 300 K. The effect of vacancies on the electronic properties is more nuanced; we see a small increase in effective mass, large increase in band gap, and decrease in carrier concentration. Ultimately, the maximumzTincreases from 0.09 to 0.7 as we go from EuCuSb to EuZn0.5Sb.  more » « less
Award ID(s):
2045122
PAR ID:
10496970
Author(s) / Creator(s):
; ; ; ; ; ; ;
Publisher / Repository:
Wiley
Date Published:
Journal Name:
Angewandte Chemie International Edition
Volume:
62
Issue:
29
ISSN:
1433-7851
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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