Choline chloride as a photosynthesis promoter is important for increasing plant yield, and we have found that it has a similar effect in perovskite solar cells (PSCs). Here, we propose the innovation of using molecular self-assembly methods to produce a choline chloride monolayer on the surface of the SnO₂; this monolayer works as a passivation layer that reduces the surface oxygen vacancies and improves the performance of CH₃NH₃PbI₃ (MAPbI₃) PSCs. The MAPbI₃ PSC based on SnO₂ modified by choline chloride (Chol-SnO₂) electron transport layer (ETL) achieves an optimal power conversion efficiency (PCE) of 18.90% under one solar illumination. The PCE is increased by 10–25% compared to the device without modification, and hysteresis is significantly reduced by eliminating the charge accumulation between the interface of the perovskite and ETL. More importantly, the MAPbI₃ PSC based on Chol-SnO₂ ETL exhibits a higher open-circuit voltage (V_OC) of 1.145 V compared to the control device (1.071 V). This work provides a very simple and effective way to improve PSC performance, which has long-term significance for the sustainable development of energy.

中文翻译：

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胆碱氯化物修饰的SnO _2可在MAPbI ₃钙钛矿太阳能电池中实现高输出电压

氯化胆碱作为光合作用的促进剂对于提高植物的产量很重要，我们发现它在钙钛矿太阳能电池（PSC）中具有类似的作用。在这里，我们提出了利用分子自组装方法在SnO ₂表面上生成氯化胆碱单层的创新方法。这种单层可以作为降低表面的氧空位，提高了CH的性能的钝化层₃ NH ₃碘化铅₃（MAPbI ₃）的PSC。基于氯化胆碱修饰的SnO ₂的MAPbI ₃ PSC （Chol-SnO ₂电子传输层（ETL）在一个太阳光照射下可达到18.90％的最佳功率转换效率（PCE）。与未经修改的设备相比，PCE增加了10–25％，并且通过消除钙钛矿和ETL界面之间的电荷积累，可以显着降低磁滞现象。更重要的是，基于Chol-SnO ₂ ETL的MAPbI ₃ PSC与控制设备（1.071 V）相比，具有更高的1.145 V开路电压（V _OC）。这项工作提供了一种非常简单有效的方法来提高PSC的性能，这对于能源的可持续发展具有长期意义。