Abstract CsPbI2Br is one of candidates of the top layer for the all perovskite tandem solar cells. However, the perovskite is prone to change the phase from α (black) to δ (yellow) type. In this research, Cs1-xFAxPbI2Br perovskites were fabricated in an ambient atmosphere, and their properties immediately after the fabrication and the phase stability were investigated. The quality of the perovskite films was enhanced and the trap density was reduced after the incorporation of the FA cations. The phase stability of the Cs1-xFAxPbI2Br perovskite was effectively enhanced. Consequently, the highest power conversion efficiency of 12.28% with open-circuit voltage (Voc) of 1.09 V, current intensity (Jsc) of 15.65 mA cm−2, and fill factor of 72% in the planar solar cell based on Cs0.7FA0.3PbI2Br perovskite is reported. The bandgap was optimized to be about 1.82 eV suitable for all perovskite tandem top layer. Most importantly, all the photovoltaic parameters of Cs0.7FA0.3PbI2Br perovskite solar cells showed ignorable decay after 2 months’ measurement in an ambient atmosphere with the presence of air and humidity without encapsulation.

中文翻译：

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通过掺入甲脒在环境气氛中提高效率和稳定性的倒置 CsPbI2Br 钙钛矿太阳能电池

摘要 CsPbI2Br 是全钙钛矿串联太阳能电池顶层的候选材料之一。然而，钙钛矿容易将相从α（黑色）转变为δ（黄色）型。在这项研究中，Cs1-xFAxPbI2Br 钙钛矿是在环境气氛中制造的，并在制造后立即研究了它们的性质和相稳定性。加入 FA 阳离子后，钙钛矿薄膜的质量得到提高，陷阱密度降低。Cs1-xFAxPbI2Br钙钛矿的相稳定性得到有效增强。因此，在基于 Cs0.7FA0 的平面太阳能电池中，最高功率转换效率为 12.28%，开路电压 (Voc) 为 1.09 V，电流强度 (Jsc) 为 15.65 mA cm-2，填充因子为 72% .3PbI2Br 钙钛矿被报道。带隙被优化为大约 1.82 eV，适用于所有钙钛矿串联顶层。最重要的是，Cs0.7FA0.3PbI2Br 钙钛矿太阳能电池的所有光伏参数在没有封装的情况下在空气和湿度存在的环境气氛中测量 2 个月后显示出可忽略的衰减。