DFT insight into structural, mechanical, electronic, optical and thermal properties of eco-friendly perovskites CuXO3 (X= Al, In)

Abstract

This report aims to investigate the structural, mechanical, optical, thermal, and electronic properties along with hardness of CuXO3 (X = Al, In) perovskites for the first time by using first-principles calculations within the density functional theory (DFT). The geometry of the both structures have been optimized by using Broyden-Fletcher-Goldfarb-Shanno (BFGS) minimization technique and confirmed as the cubic structure with the space group of P m‾ 3 m (No. 221). The studied lattice parameters of CuXO3 (X = Al, In) closely resemble with previous theoretical and experimental results. Both the compounds of CuXO3 (X = Al, In) under investigation are mechanically stable as the calculated elastic constants satisfy the Born stability criteria. The calculated value of Pugh's ratio, Poisson's ratio and Cauchy pressure confirm strong ductility behavior in contrast to brittleness of these compounds. The elastic anisotropy calculations confirm the anisotropic nature in CuAlO3 in contrast to isotropic nature as observed in CuInO3. CuAlO3 is predicted to be harder than that of CuInO3. CuInO3 shows the highest machinability index among studied compounds. The electronic band-structure and density of states ensure semiconducting nature in CuAlO3 whereas, CuInO3 reveals metallic nature. The investigation of optical properties reveals the prospective application of the entitled substances in a wide range of electronic and optoelectronic device uses. The title compounds could be used as thermal barrier coating materials (TBC) for exhibiting low thermal conductivity.