Inorganic and Pb-Free CsBi <sub/>3</sub> I <sub/>10</sub> Thin Film for Photovoltaic Applications

摘要： Computational, thin-film deposition and characterization approaches have been used to investigate the all inorganic lead-free CsBi3I10 as a candidate thin-film photovoltaic absorber. In this paper, CsBi3I10 was firstly predicted with a layer crystal structure of stable hexagonal phase like Cs3Bi2I9 and then prepared by one-step coating also showing the high purity hexagonal phase and crystallinity, very consistent with the theoretical calculation. After solvent annealing, a high absorption coefficient of approximately 105 cm?1 in visible light and a suitable optical bandgap of 1.78 eV were obtained for CsBi3I10 thin film. The solar cell based on CsBi3I10 perovskite thin film exhibited high power conversion efficiency of 1.05%, good reproducibility, hysteresis-freeness, and long-term stability. These results indicate that the performance of all-inorganic Pb-free perovskite solar cells can be further improved.