High-PerformanceCsPbIBr 2 Perovskite SolarCells: Effectively Promoted Crystal Growth by Antisolvent and OrganicIon Strategies

Growing attention has been paid to CsPbIBr2 perovskite solar cells (PSCs) after balancing the band gap and stability features of the interested full-inorganic perovskites. However, their power-conversion efficiency (PCE) still lags behind that of the PSCs using hybrid halide perovskite and how to increase the corresponding PCE is still a challenge. Herein, antisolvents and organic ion surface passivation strategies were systematically applied to precisely control the growth of CsPbIBr2 crystals for constructing a high-quality full-inorganic perovskite film. Through careful adjustments, a CsPbIBr2 film with a pure phase, full coverage, and high crystallinity with preferable (100) orientation was successfully obtained by introducing diethyl ether as the antisolvent followed by guanidinium surface passivation. The optimal CsPbIBr2 film was composed by a large grain with an average size of 950 nm, few grain boundaries, and higher hydrophobic property. Planer PSC using the optimal CsPbIBr2 film and electron-be...