First-Principles Studies of Structures and Electronic Properties of Co4Sb12-2xTexGex Skutterudites

Published

February 3, 2016

Author(s)

Winnie K. Wong-Ng, Izaak Williamson, Logan J. Her, Xianli Su, Yonggao Yan, Lan Li

Abstract

The structures and electronic properties of Co4Sb12-2xTexGex compounds (x = 0, 0.5, 1, 2 & 3) have been studied using density functional theory-based structure and electronic structure calculations. As Te/Ge substitution concentration increases, lattice parameters generally decrease. Cell angle γ and Co-Sb/Te/Ge bond distances also vary. The order-disorder transition is observed due to the different configurations of four-member pnicogen rings at x = 3. Structural distortion indicates that the symmetry of the Co4Sb12-2xTexGex compound is not perfectly cubic. Density of states (DOS) exhibits band gap changes, predicting relatively low electrical conductivity at x = 0 with a large band gap and high electrical conductivity at x = 3 with no band gap. In local DOS, orbital hybridization occurs between Co and Te/Ge, resulting in the covalent characteristics of Co-Te/Ge bonds.

Citation

Applied Physics Letters

Volume

119

Pub Type

Journals

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DOI Link

Keywords

Co4Sb12-2xTexGex, Skutterudites, structure and electronic properties, first-principles studies

Citation

Wong-Ng, W. , Williamson, I. , Her, L. , Su, X. , Yan, Y. and Li, L. (2016), First-Principles Studies of Structures and Electronic Properties of Co4Sb12-2xTexGex Skutterudites, Applied Physics Letters, [online], https://doi.org/10.1063/1.4940952 (Accessed April 26, 2024)