SnO₂ as an electron transport layer (ETL) has recently been used for perovskite solar cells (PSCs) due to high transmittance and electron mobility. However, the mismatched band energy alignment of ETL and perovskite layer result in serious nonradiative recombination limiting the improvement of PSCs performance. Here, 2-(Diphenylphosphino)ethanaminium tetrafluoroborate (DPEBF₄) as buried interface was introduced between ETL and perovskite. The [BF₄]⁻ anion in DPEBF₄ can interact with SnO₂ to reduce the surface defect of SnO₂. While [DPE]⁺ cation is more inclined to interact with Pb²⁺ and I⁻, the terminal strong interaction will promote crystallization of perovskite film quality and passivate buried surface defects. As a result, device performance was significantly improved by introducing DPEBF₄ layer, the power conversion efficiency (PCE) increase from 20.50 % for control devices to 23.84 %. The work provides an interfacial double-tonic strategy for ETL and perovskite crystals to achieve high-performance perovskite photovoltaic devices.

SnO₂ 作为电子传输层 (ETL)，由于具有高透过率和电子，最近被用于钙钛矿太阳能电池 (PSC)流动性。然而，ETL和钙钛矿层的能带能量排列不匹配导致严重的非辐射复合，限制了PSC性能的提高。在此，在 ETL 和钙钛矿之间引入了 2-(二苯基膦)乙胺四氟硼酸盐 (DPEBF₄) 作为掩埋界面。 DPEBF中的[BF₄]⁻阴离子< a i=9>4可以与SnO₂相互作用，减少SnO的表面缺陷₂。而[DPE]⁺阳离子更倾向于与Pb相互作用²⁺和I⁻，终端强相互作用将促进钙钛矿薄膜质量的结晶并钝化埋藏的表面缺陷。结果，通过引入DPEBF₄层，器件性能得到显着提升，功率转换效率（PCE）从控制器件的20.50%提高到23.84% 。该工作为ETL和钙钛矿晶体提供了一种界面双调策略，以实现高性能钙钛矿光伏器件。