Volatile, CH₃NH₃⁺-free, [CH(NH₂)₂]_0.9Cs_0.1PbI₃ organic-inorganic perovskite thin films were treated with fluorinated ammonium iodide {4-fluoro-phenethylammonium iodide (4F-PEAI)} solution and thin two-dimensional (4F-PEA)₂PbI₄ films were formed on the surface, resulting in a significant improvement in photoluminescence intensity. When applied to low-temperature-processed PSCs with planar structure, untreated PSCs exhibited PCEs of 18.6% and 17.0% during reverse and forward scanning, respectively. The PSCs treated with 4F-PEAI showed improved open-circuit voltage, fill factor, and PCEs of 20.6% and 18.5% during reverse and forward scanning, respectively.

挥发性无CH ₃ NH ₃ ^+的[CH（NH ₂）₂ ] _0.9 Cs _0.1 PbI ₃有机-无机钙钛矿薄膜用氟化碘化铵{4-氟-苯基乙基碘化铵（4F-PEAI）}溶液处理，并薄二维（4F-PEA）₂ PbI ₄在表面上形成膜，导致光致发光强度显着提高。当应用于具有平面结构的低温处理的PSC时，未经处理的PSC在反向和正向扫描过程中的PCE分别为18.6％和17.0％。用4F-PEAI处理的PSC在反向和正向扫描过程中的开路电压，填充系数和PCE分别提高了20.6％和18.5％。