Fabricating electron transport layers at low temperatures is challenging but highly desired in the field of flexible perovskite solar cells (f-PSCs). In this study, highly uniform cerium oxide (CeO_x) films prepared by the UV–O₃ treatment have been successfully applied as the electron transport layer (ETL) in methylammonium lead halide (CH₃NH₃PbI₃) perovskite-based f-PSCs. Under AM 1.5 G sunlight with 100 mW cm⁻², these cells exhibited an open-circuit voltage (V_oc) of 0.98 V, a short-circuit current density (J_sc) of 19.42 mA cm⁻², a fill factor (FF) of 0.72 and power conversion efficiency (PCE) of 14.63%. The PCE was much higher than that of the control planar CeO_x ETL (PCE ∼ 9.08%) prepared at a low temperature (80 °C) without the UV–O₃ treatment, and this was ascribed to the improved CeO_x film, enhanced light absorption and suppressed charge recombination. The cells that bend at 15 mm of radius showed excellent stability with less than 10% reduction in PCE after 500 cycles of repeated bending at ambient temperature. The charge-transmission kinetic parameters and long-term stability of the CeO_x-based f-PSCs were analyzed as well.

中文翻译：

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UV-O3 处理的无退火氧化铈作为柔性平面钙钛矿太阳能电池中的电子传输层

在低温下制造电子传输层具有挑战性，但在柔性钙钛矿太阳能电池（f-PSC）领域非常需要。在这项研究中，通过 UV-O ₃处理制备的高度均匀的氧化铈 (CeO _x ) 薄膜已成功应用于甲基铵卤化铅 (CH ₃ NH ₃ PbI ₃ ) 钙钛矿基 f-中的电子传输层 (ETL)。 PSC。在 100 mW cm ^-2的 AM 1.5 G 阳光下，这些电池的开路电压 ( V _oc ) 为 0.98 V，短路电流密度 ( J _sc ) 为 19.42 mA cm ^-2，填充因子 (FF) 为 0.72，功率转换效率 (PCE) 为 14.63%。PCE 远高于未经 UV-O ₃处理的低温（80 °C）制备的对照平面 CeO _x ETL（PCE ∼ 9.08%） ，这归因于改进的 CeO _x薄膜，增强了光吸收和抑制电荷复合。在环境温度下重复弯曲 500 次后，以 15 mm 半径弯曲的电池表现出出色的稳定性，PCE 降低不到 10%。_{还分析了基于 CeO x}的 f-PSC的电荷传输动力学参数和长期稳定性。