Hui Wei, Kang Xinxin, Wang Baohua, Li Deli, Su Zhenhuang, Bao Yaqi, Gu Lei, Zhang Biao, Gao Xingyu, Song Lin, Huang Wei
Frontiers Science Center for Flexible Electronics (FSCFE), Institute of Flexible Electronics (IFE), Northwestern Polytechnical University, 127 West Youyi Road, Xi'an 710072, P. R. China.
Fujian Cross Strait Institute of Flexible Electronics (Future Technologies), Fujian Normal University, Fuzhou 350117, P. R. China.
Nano Lett. 2023 Mar 22;23(6):2195-2202. doi: 10.1021/acs.nanolett.2c04720. Epub 2023 Mar 13.
Due to their low cost and simplified production process, electron-transport-layer-free (ETL-free) perovskite solar cells (PSCs) have attracted great attention recently. However, the performance of ETL-free PSCs is still at a disadvantage compared to cells with a conventional n-i-p structure due to the severe recombination of charge carriers at the perovskite/anode interface. Here, we report a strategy to fabricate stable ETL-free FAPbI PSCs by in situ formation of a low dimensional perovskite layer between the FTO and the perovskite. This interlayer gives rise to the energy band bending and reduced defect density in the perovskite film and indirect contact and improved energy level alignment between the anode and perovskite, which facilitates charge carrier transport and collection and suppresses charge carrier recombination. As a result, ETL-free PSCs with a power conversion efficiency (PCE) exceeding 22% are achieved under ambient conditions.
由于其低成本和简化的生产工艺，无电子传输层（ETL-free）的钙钛矿太阳能电池（PSC）最近受到了极大关注。然而，由于钙钛矿/阳极界面处电荷载流子的严重复合，无ETL的PSC的性能与具有传统n-i-p结构的电池相比仍处于劣势。在此，我们报告了一种通过在FTO和钙钛矿之间原位形成低维钙钛矿层来制备稳定的无ETL的FAPbI PSC的策略。该中间层导致钙钛矿薄膜中的能带弯曲和缺陷密度降低，以及阳极与钙钛矿之间的间接接触和能级对准改善，这有利于电荷载流子的传输和收集，并抑制电荷载流子复合。结果，在环境条件下实现了功率转换效率（PCE）超过22%的无ETL的PSC。
