Strain engineering on the electronic bands, mechanical stability, thermal, vibrational and thermoelectric response of PtScSb half-Heusler semiconductor

Abstract

The noteworthy and dynamic aspects of materials science is to predict an innovative and versatile compounds that enfolds the colossal reaction by the executions of applied stress that imparts the gateway in applied fields. A prompt illustration for enhancement of variability of materials is characteristically established on first principles technique for enlightenment in the variability of compounds. The present manuscript delivers a widespread examination of strain dependent properties including lattice dynamics, thermophysical, mechanical and most significant thermoelectric properties at various levels of PtScSb Heusler material. The impact of applied isotropic strain ranging (−12 % to +4 %) has been keenly scrutinized. From the calculated elastic parameters including Pugh ratio, Young's modulus, Poisson ratio etc., we noticed that a decline trend is observed with the tensile strain and reveals an escalation with the compressive strain. The calculated mechanical parameters (Pugh's and Poisson) validated that the present material is brittle by the application of applied strain. With the intensification in the strain typically up to −12 %, material displays a ductile performance. Additionally, with the escalation of +4 % of tensile strain the present alloy lends towards brittle one. From the examination of bands, the energy band gap drops significantly with intensification in the tensile strength and the escalations of the strain factor. The applied strain effect on lattice dynamics approves the robust stability of PtScSb half Heusler material. The thermoelectric parameters including (lattice thermal conductivity, Seebeck coefficient, electrical conductivity, figure of merit) have been keenly checked at numerous strain levels that approves the material for waste heat recovery systems and as well as technological aspects. The parameters like Debye temperature, Grüneisen parameter etc., have also been predicted at various strain levels to check its thermal stability.