First-Principles Investigations of Thermoelectric Behavior of RuCrX (X = Si, Ge, Sn).

Abstract

The half-Heusler alloys have not only been recognized for spintronic and memory devices but also for thermoelectric applications. In this research work, the detailed study for thermoelectric parameters of RuCrX (X = Si, Ge, Sn) half-Heusler alloys has been carried out by using the pseudopotential approach alongside the Boltzmann transport theory. The RuCrX (X= Si, Ge, Sn) was reported stable in C1 b -type structure by means of energy-volume optimization, elastic stability criteria, positive phonon frequencies in phonon dispersion curves, and formation energies. The all important thermoelectric properties of these alloys have not yet been explored. The thermoelectric properties such as Seebeck coefficient, electronic part of thermal conductivity, electrical conductivity, and power factor have been discussed within a specific temperature range (300-1200 K). The calculated value of the power factor was found to be 5.11 × 1011 W/(m K2 s) for RuCrSi, 3.42 × 1011 W/(m K2 s) for RuCrGe, and 1.85 × 1011 W/(m K2 s) for RuCrSn at 1200 K.