CH3NH3PbI3-xBrx perovskite solar cells via spray assisted two-step deposition: influence of bromide on the device performance

In this study, we demonstrated full conversion of PbI
₂
to perovskite via our spray assisted two-step deposition method and achieved solar cells with 13% efficiency. Moreover, the influence of adding MABr in the PbI
₂
solution in the first step on the resulting solar cells is investigated for the first time. The perovskite solar cells prepared in this manner showed a significant increase in the power conversion efficiency after one-night storage, and a process of Br ions diffusion is proposed.