First principles studies on optoelectronics and transport properties of KSrY (Y = Sb, Bi) for renewable energy application

Abstract

Currently, producing equipment and goods of all kinds that are economical, energy-efficient, and ecologically friendly is the main objective. In this study, an attempt has been made to look into these materials that meet these requirements. The structural, elastic, optoelectronic and transport characteristics of KSrY (Y = Sb,Bi) Half-Heusler were studied employing Full-potential, linearized augmented plane wave programs (FP_LAPW) approach as embedded in WIEN2K. The structural optimization was performed employing generalized gradient approximation (GGA). The computed lattice constants were reasonable in compliance with previous theoretical and experimental findings. The investigated KSrY (Y = Sb,Bi) were mechanically stable and brittle by nature. The KSrY (Y = Sb,Bi) compounds are discovered to have semiconducting nature with direct bandgap. The magnitudes of the bandgap for the KSrBi and KSrSb are 1.749 eV and 2.457 eV, respectively, using the mBJ approximation. The investigated materials on the basis of calculated band gap and optical spectra demonstrate the ability of the compounds to absorb both visible and UV light, henceforth application in optoelectronic devices. The Boltzmann transport theory included in the BoltzTraP package was used to study thermoelectric characteristics. The obtained figures of merit (ZT) values for the KSrY (Y = Bi, Sb) compounds are all close to unity at room temperature, suggesting optimum thermoelectric efficiency can be employed in thermoelectric devices.