DFT insights via HSE03 functional into the formation energy, electronic, optical, and elastic properties of lead free inorganic halide perovskites for photovoltaic application
摘要
In the family of advanced perovskite materials, inorganic cubic halide perovskites have attracted significant attention because of their flexible chemistry and outstanding ionic conductivity. Herein, density functional theory calculations were performed within the WIEN2k framework using the HSE03 hybrid functional to investigate the structural, optoelectronic, elastic, and mechanical properties of inorganic cubic halide perovskites KNiBr3. The material exhibits band gap of 1.544 eV, which lies within the optimal range for photovoltaic applications. Optical properties reveal strong absorption, high conductivity, and minimal energy loss, indicating significant potential for photovoltaics. The calculated elastic constants (C11, C12, and C44) satisfy the Born stability criteria, suggested that studied material exhibits elastic stability. Furthermore, mechanically derived parameters, including elastic anisotropy, Poisson’s ratio (ʋ), and Pugh’s ratio (B/G), confirmed the anisotropic and ductile, while its thermal behavior is characterized by the Debye temperature (θD). These outcomes indicated that the designed halide perovskite, KNiBr3, as a highly promising material for photovoltaic and related technological applications.