A density functional theory study of the structural, mechanical, optoelectronics and thermoelectric properties of InGeX3 (X = F, Cl) perovskites

Abstract

Structural, electronic, lattice dynamics, optical, elastic, and thermoelectric features of Indium based Perovskite InGeX3 (X = F, Cl) are studied by using WIEN2k code within density functional theory DFT. A level of the Boltzmann transport theory is used to derive electronic transport coefficients together with anticipated electronic relaxation times. These compounds exhibit stability and are cubic with the space group Pm-3m 221, according to the structural analysis. The band structure having the 2.15 eV and 1.29 eV band gap and density of state (DOS) are calculated for electronic characteristics, indicating that both compounds are semiconducting. For the analysis of elastic characteristics, elastic constants, bulk modulus (49.99, 22.69), Poisson’s ratio (0.343, 0.261), anisotropy factor (0.52, 0.59), and Pugh’s ratio (2.87, 1.75) are examined. The ductile nature of the compounds is described by Pugh’s ratio, and the ionic nature can be ascertained by evaluating the Cauchy pressure. In the energy range of 0–10 eV, optical features like reflectivity, optical conductivity, refractive index, extinction coefficient and absorption coefficient are computed. These compounds broad-range absorption in the UV spectrum suggests that they could be good optoelectronic device candidates. The transport feature like Seebeck coefficient, thermal and lattice conductivity, power factor, electrical conductivity, and figure of merit zT (0.99, 0.98) can be calculated against temperature. The chemical potential against an excellent thermoelectric property of InGeX3 (X = F, Cl) have high figure of merit due to high Seebeck and electrical conductivity. These predicted outcomes indicated that both compounds are suitable candidates for thermoelectric applications. Such compounds can replace with other renewable energy sources in thermoelectric devices because of their powerful thermoelectric response.