Over the years, the efficiency of inorganic perovskite solar cells (PSCs) has increased at an unprecedented pace. However, energy loss in the device has limited a further increase in efficiency and commercialization. In this work, we used (NH₄)₂C₂O₄·H₂O to treat CsPbBrI₂ perovskite film during spin-coating. The CsPbBrI₂ underwent secondary crystallization to form high quality films with micrometer-scale and low trap density. (NH₄)₂C₂O₄·H₂O treatment promoted charge transfer capacity and reduced the ideal factor. It also dropped the energy loss from 0.80 to 0.64 eV. The resulting device delivered a power conversion efficiency (PCE) of 16.55% with an open-circuit voltage (V_oc) of 1.24 V, which are largely improved compared with the reference device which exhibited a PCE of 13.27% and a V_oc of 1.10 V. In addition, the optimized treated device presented a record indoor PCE of 28.48% under a fluorescent lamp of 1000 lux, better than that of the reference device (19.05%).

多年来，无机钙钛矿太阳能电池 (PSC) 的效率以前所未有的速度提高。然而，设备中的能量损失限制了效率和商业化的进一步提高。在这项工作中，我们使用(NH ₄ ) ₂ C ₂ O ₄ ·H ₂ O在旋涂过程中处理CsPbBrI _{2钙钛矿薄膜。}CsPbBrI ₂经过二次结晶形成具有微米级和低陷阱密度的高质量薄膜。(NH ₄ ) ₂ C ₂ O ₄ ·H ₂O 处理提高了电荷转移能力并降低了理想因素。它还将能量损失从 0.80 降低到 0.64 eV。所得器件的功率转换效率 (PCE) 为 16.55%，开路电压 ( V _oc ) 为 1.24 V，与参考器件相比有了很大提高，参考器件的 PCE 为 13.27%，V _oc为 1.10五、此外，经过优化处理的设备在 1000 勒克斯荧光灯下的室内 PCE 达到创纪录的 28.48%，优于参考设备（19.05%）。