Stability and Thermoelectric Properties of Transition Metal Silicides from First Principles Calculations

Abstract

We report an ab-initio study of the stability and electronic properties of transition metal silicides in order to study their potential for high temperature thermoelectric applications. We focus on the family M 5 Si 3 (M = Ta, W) which is stable up to about 2000 °C. We first investigate the structural stability of the two compounds and then determine the thermopower of the equilibrium structure using the electronic density of states and Mott's law. We find that W 5 Si 3 has a relatively large thermopower but probably not sufficient enough for thermoelectric applications.