Interfacial modification is crucial to fully develop the potential of semiconductor devices, including the revolutionary halide perovskite-based optoelectronics, such as photovoltaics, light-emitting diodes, and photodetectors. The all-inorganic halide perovskites, which are potential long-term stable photovoltaic materials, are suffering from poor interfacial contact with metal oxide charge-selective layer, severely limiting the power conversion efficiency and stability of inorganic perovskite solar cells. Here, we propose an intermediate-phase engineering strategy to improve the inorganic perovskite/metal oxide interface by utilizing volatile salts. The introduction of organic cations (such as methylammonium and formamidinium), which can be doped into the perovskite lattice, leads to the formation of an organic-inorganic hybrid perovskite intermediate phase, promoting a robust interfacial contact through hydrogen bonding. A champion CsPb(I_0.75Br_0.25)₃-based device with a power conversion efficiency of 17.0% and an open-circuit voltage of 1.34 V was realized, implying that a record of over 65% of the Shockley-Queisser efficiency limit is achieved.

界面改性对于充分开发半导体器件的潜力至关重要，包括革命性的基于卤化钙钛矿的光电器件，例如光伏器件，发光二极管和光电探测器。全无机卤化物钙钛矿是潜在的长期稳定的光伏材料，与金属氧化物电荷选择层的界面接触不良，严重限制了无机钙钛矿太阳能电池的功率转换效率和稳定性。在这里，我们提出了一种中间阶段工程策略，以通过利用挥发性盐来改善无机钙钛矿/金属氧化物的界面。引入可以掺入钙钛矿晶格中的有机阳离子（例如甲基铵和甲ami），导致形成有机-无机杂化钙钛矿中间相，并通过氢键促进牢固的界面接触。冠军CsPb（I基于_0.75 Br _0.25）₃的器件，实现了17.0％的功率转换效率和1.34 V的开路电压，这意味着创下了Shockley-Queisser效率极限的65％以上的记录。