First-Principles Study of Aziridinium Lead Iodide Perovskite for Photovoltaics.

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 (CH2 )2 NH2 PbI3 (AZPbI3 ), which exhibits a much better stability than the popular halide perovskites CH3 NH3 PbI3 and HC(NH2 )2 PbI3 , by using density functional theory (DFT). We find that AZPbI3 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 CH3 NH3 PbI3 and HC(NH2 )2 PbI3 materials in the whole visible-light region. In addition, the conductivity of AZPbI3 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 AZPbI3 according to our calculations. Overall, we suggest that the perovskite AZPbI3 is an excellent candidate as a stable high-performance photovoltaic absorber material.