Liu Cheng, Yang Yi, Ding Yong, Xu Jia, Liu Xiaolong, Zhang Bing, Yao Jianxi, Hayat Tasawar, Alsaedi Ahmed, Dai Songyuan
Beijing Key Laboratory of Novel Thin-Film Solar Cells, North China Electric Power University, Beijing, 102206, P. R. China.
NAAM Research Group, Department of Mathematics, Faculty of Science, King Abdulaziz University, Jeddah, 21589, Saudi Arabia.
ChemSusChem. 2018 Apr 9;11(7):1232-1237. doi: 10.1002/cssc.201702248. Epub 2018 Mar 8.
Efficient metal-halide perovskite solar cells (PSCs) with a regular structure typically use high-temperature-processed TiO electron-transport layers (ETLs), which suffer from high electron recombination and inherent UV instability. Herein, we present low-temperature solution-processed lithium bis(trifluoromethanesulfonyl)imide (Li-TFSI)-doped C (Li-C ) ETLs for high-efficiency and UV-stable planar PSCs with an n-i-p architecture. We found that simple Li-TFSI doping ensured a better energy match between the active layer and the cathode, considerably enhanced the electron mobility of the ETL, and even improved CH NH PbI crystallization finally to increase the power conversion efficiency (PCE) from 15.3 to 17.8 % with a minor hysteresis effect. Moreover, it was demonstrated that replacing TiO with Li-C resulted in PSCs that were much more stable under UV light under an air atmosphere with almost no degradation after 3000 h under a nitrogen atmosphere.
具有常规结构的高效金属卤化物钙钛矿太阳能电池（PSC）通常使用经过高温处理的TiO电子传输层（ETL），这种ETL存在高电子复合和固有的紫外线不稳定性问题。在此，我们展示了用于具有n-i-p结构的高效且紫外线稳定的平面PSC的低温溶液处理的双（三氟甲磺酰）亚胺锂（Li-TFSI）掺杂的C（Li-C）ETL。我们发现简单的Li-TFSI掺杂确保了活性层与阴极之间更好的能量匹配，显著提高了ETL的电子迁移率，甚至最终改善了CH₃NH₃PbI₃的结晶，从而将功率转换效率（PCE）从15.3%提高到17.8%，且滞后效应较小。此外，结果表明用Li-C取代TiO会使PSC在空气气氛下的紫外光下更稳定，在氮气气氛下3000小时后几乎没有降解。
