Assessment of thermoelectric performance of Cu2ZnSnX4, X=S, Se, and Te

Abstract

A recent experiment on In-doped Cu 2 ZnSnSe 4 [X. Y. Shi et al., Appl. Phys. Lett.94, 122103 (2009)] has shown promising thermoelectric performance characteristics. In this letter, we analyze relevant electronic and transport properties of Cu 2 ZnSnSe 4 and similar compounds, Cu 2 ZnSnS 4 and Cu 2 ZnSnTe 4 , to assess their potential as thermoelectric materials. Using density functional theory and Boltzmann transport equations, we determine Seebeck coefficients, conductivities, and power factors of closely related polymorphs with space groups, I 4 ¯ , I 4 ¯ 2 m , and P 4 ¯ 2 m for each compound. Based on their electronic structure and transport properties, we conclude that other two compounds could have similar potential as thermoelectric materials.