A first-principles study of the unsynthesized Indium halide perovskites RbInX₃ (X= F, Cl, Br, I) for photovoltaic and photocatalytic applications

Laboratory of Condensed Matter and Interdisciplinary Sciences, Unité de Recherche labellisée CNRST, URL-CNRST-17, Faculty of Sciences, Mohammed V University of Rabat, Morocco

Abstract

Due to their relevant properties, lead-free halide perovskites have attracted wide attention in the scientific community. This study investigates the structural, mechanical, electronic, optical, and photocatalytic properties of the Indium-based halide perovskites RbInX3 (X= F, Cl, Br, I) based on the density functional theory (DFT) using the WIEN2k package. The results show that RbInI3 exhibits a metallic behavior, while RbInBr₃, RbInCl₃, and RbInF₃ exhibit semiconducting behavior with bandgap energies of 0.67, 1.43, and 2.45 eV, respectively. The high optical absorption and corresponding band gap energies make them good candidates for photovoltaic applications. In addition, the RbInF3 compound exhibits good photocatalytic performance since it satisfies the thermodynamic requirements needed to trigger the water-splitting reaction. This study also allows us to analyze the influence of halogen substitution on the properties of the compound RbInX3. Moreover, it will open the way to the experimental community as it is the first to study the properties of these perovskites.