Structural, vibrational, electronic, thermodynamic and thermoelectric properties of CaCdSi Half Heusler compound: A first-principles study

Abstract

The new half-Heusler CaCdSi alloy, as a new crucial nonmagnetic thermoelectric candidate, is desired to be understood in terms of its potential physical properties and stability in both experimental and theoretical studies. Here we investigate the thermal properties of half-Heusler CaCdSi using the plane-wave pseudopotential approach based on the density functional theory within the generalized gradient approximation (GGA). Firstly, dynamical and mechanical stability was assured in its cubic phase. These results also elucidate the stable and brittle nature of the compound. Furthermore, electronic band structure calculation shows that the CaCdSi alloy has semiconductor behavior with a direct band gap of 0.59 eV. Lastly, the Seebeck coefficient, electronic conductivity, electronic thermal conductivity, the power factor, and figure of merit have been investigated using the semi-classical Boltzmann transport theory. The high value of ZT of the CaCdSi alloy makes it a potential candidate material for thermoelectric applications. Our research not only enriches the family of thermoelectric materials but also provides a good platform for further experimental investigations.