Theoretical Insights into Photovoltaic Application of a Novel Family of Perovskite‐Inspired Pb‐Free Metal Halide Materials

Abstract

Organic–inorganic halide perovskite have shown great promise for photovoltaic applications due to their unprecedented optoelectronic properties and low manufacturing cost. However, the commercialization of this emerging technology is hampered by its thermal instability and intrinsic Pb‐toxicity. Here, we report first‐principles investigations on stability and optoelectronic properties of a series of all‐inorganic lead‐free metal halide perovskite‐like materials AMX4 (A = Cs, Ag, and Rb; M = In, Sb, and Bi; X = Cl, Br, and I). Our calculations show that AgSbI4 and AgBiI4 have direct bandgaps of 1.63 and 1.44 eV, which possess strong interband optical absorption (≈105 cm−1). Based on these favorable properties, we also simulated the AgSbI4‐ and AgBiI4‐based thin film solar cells with the SCAPS‐1D code and achieve high PCE of 24.19% and 26.70%, respectively. These results reveal that the AMX4 perovskite‐like materials could serve as potential alternatives to Pb‐based halide perovskites in photovoltaic devices.