Comprehensive study of Sr2VInO6 and Sr2VTlO6: Structural, mechanical, optoelectronic and thermoelectric properties

Abstract

The structural, mechanical, optoelectronic, and thermoelectric properties of Sr${}_2$VInO${}_6$ and Sr${}_2$VTlO${}_6$ were investigated using the full potential linearized augmented plane wave (FP-LAPW) method. The structural and thermodynamic stability were confirmed by calculating their tolerance factors of 0.92 and 0.90 and negative formation energies of $-0.86$ eV/atom and $-0.78$ eV/atom, respectively. Both compounds are p-type indirect band gap semiconductors with gaps of 2.30 eV and 2.15 eV. Mechanical characterization using Pugh’s and Poisson’s ratios indicates the ductile nature of the compounds. A large absorption coefficient and conductivity in both the visible and ultraviolet regions ensure the potential of the studied compounds for renewable energy applications in ultraviolet–visible regions. Thermoelectric assessment shows low lattice thermal vibration at room temperature and figure of merit values of 0.63 (Sr${}_2$VInO6) and 0.73 (Sr${}_2$VTlO${}_6$) at 1000K, highlighting their efficiency for optoelectronic and thermoelectric applications with Sr${}_2$VTlO${}_6$ demonstrating higher optical and thermal activity compared to Sr${}_2$VInO${}_6$.