Flexible perovskite solar cells were prepared using two-step solution-processed SnO₂ layers as electron-transport-material. The first layer was constructed by hydrothermal derived SnO₂ nanoparticles, and the second layer was in-situ formed from hydrolysis and oxidization of SnCl₂. It was observed that the two-step formed SnO₂ layers could efficiently improve the device performance of the flexible perovskite solar cells. Without such layers, no photovoltaic effect was observed due to poor wettability of substrate. After SnO₂ was deposited, power conversion begins due to improved crystallinity of perovskite layer. Compared with one-step processed SnO₂ layer, the two-step processed SnO₂ layers could take the advantages of accelerated charge extraction, lowered contact resistance, as well as reduced charge recombination, which help to upgrade open circuit voltage, short circuit current, fill factor and power conversion efficiency of the flexible devices. Device efficiency of 15.21% (AM 1.5 G, 100 mW/cm²) was obtained for the flexible devices, with prolonged shelf-stability in addition. After being stored in dark for 111 days (relative humidity of 35–55%, no encapsulation was used), device could keep 85% of starting efficiency. Meanwhile, specific power (ratio between power and device weight) of 0.87 kW/kg was obtained, as well as sound fatigue ability against bending. The solution based two-step formation process thus provides a reliable strategy for future application of flexible perovskite solar cells.

使用两步固溶处理的SnO ₂层作为电子传输材料，制备了柔性钙钛矿太阳能电池。第一层由水热衍生的SnO ₂纳米颗粒构成，第二层由SnCl _2的水解和氧化原位形成。观察到两步形成的SnO ₂层可以有效地改善柔性钙钛矿太阳能电池的器件性能。没有这样的层，由于基板的可湿性差而未观察到光伏效应。在SnO ₂沉积之后，由于钙钛矿层结晶度的提高，开始了功率转换。与一步处理的SnO ₂层相比，两步处理的SnO ₂层₂层可以利用加速电荷提取，降低接触电阻以及减少电荷复合的优势，这有助于提高柔性器件的开路电压，短路电流，填充因子和功率转换效率。装置效率为15.21％（AM 1.5 G，100 mW / cm ²获得了用于柔性设备的），此外还具有延长的储存稳定性。在黑暗中存放111天（相对湿度为35–55％，未使用封装）后，设备可以保持85％的启动效率。同时，获得的比功率（功率与设备重量的比）为0.87 kW / kg，并且具有抗弯曲的声音疲劳能力。因此，基于解决方案的两步成型工艺为柔性钙钛矿太阳能电池的未来应用提供了可靠的策略。