Ab initio calculations of structural, optical and thermoelectric properties for CoSb 3 and ACo 4Sb 12(A = La, Tl and Y) compounds

Abstract

We present the structural, optical and thermoelectric properties of unfilled and filled CoSb 3. The full potential linearized augmented plane wave (FP-LAPW) method within the generalized gradient approximation (GGA) is used to investigate the optoelectronic properties and for thermoelectric properties we have used the semi-classical Boltzmann transport theory. The calculated fundamental band gap of unfilled CoSb 3 at Γ symmetry point is 0.036 eV. Furthermore, filling of CoSb 3 by A (A = La, Tl and Y) strongly affects the optoelectronic properties and carrier concentration of this compound. The bulk modulus of the unfilled CoSb 3 is smaller than that of filled CoSb 3 with Tl and Y. The results of study predict that the filling of Tl effectively enhances the efficiency of the thermoelectric properties of CoSb 3.