First‐Principles Study of Aziridinium Lead Iodide Perovskite for Photovoltaics

Abstract The long‐term stability remains one of the main challenges for the commercialization of the rapidly developing hybrid organic‐inorganic perovskite solar cells. Herein, we investigate the electronic and optical properties of the recently reported hybrid halide perovskite (CH 2 ) 2 NH 2 PbI 3 (AZPbI 3 ), which exhibits a much better stability than the popular halide perovskites CH 3 NH 3 PbI 3 and HC(NH 2 ) 2 PbI 3 , by using density functional theory (DFT). We find that AZPbI 3 possesses a band gap of 1.31 eV, ideal for single‐junction solar cells, and its optical absorption is comparable with those of the popular CH 3 NH 3 PbI 3 and HC(NH 2 ) 2 PbI 3 materials in the whole visible‐light region. In addition, the conductivity of AZPbI 3 can be tuned from efficient p ‐type to n ‐type, depending on the growth conditions. Besides, the charge‐carrier mobilities and lifetimes are unlikely hampered by deep transition energy levels, which have higher formation energies in AZPbI 3 according to our calculations. Overall, we suggest that the perovskite AZPbI 3 is an excellent candidate as a stable high‐performance photovoltaic absorber material.