南京大学谭海仁团队报道了定制的二维钙钛矿实现全钙钛矿叠层均匀化接触。相关研究成果发表在2024年10月14日出版的《自然》。

制造可扩展的全钙钛矿叠层太阳能电池被认为是将钙钛矿光伏模块商业化的一条有吸引力的途径。然而，1-cm²规模的全钙钛矿叠层太阳能电池的认证效率落后于其小面积（~0.1 cm²）的对应产品。这种性能缺陷源于大规模宽带隙（WBG）钙钛矿太阳能电池（PSCs）的不均匀性。已知不均匀性是在底部界面和钙钛矿块体本身引入的。

该文中，研究发现了不均匀性的另一个关键来源——在电子传输层（ETL，C60）沉积过程中形成的顶部界面。同时，糟糕的ETL接口也是设备性能的一个重大限制。

研究人员通过引入4-氟苯乙胺（F-PEA）和4-三氟甲基苯基铵（CF3-PA）的混合物，来创建定制的二维钙钛矿层（TTDL）来解决这个问题，其中F-PEA在表面形成二维钙钛矿，减少了接触损失和不均匀性，CF3-PA增强了电荷提取和传输。因此，研究人员在平方厘米尺度上，证明了1.77-eV WBG PSCs的1.35 V的高开路电压和20.5%的效率。

通过与窄带隙钙钛矿子电池堆叠，报告了1.05 cm²的全钙钛矿串联电池，其效率为28.5%（经认证为28.2%），是迄今为止报告的所有电池中最高的。

研究工作展示了处理顶部钙钛矿/ETL触点对于升级钙钛矿太阳能电池的重要性。

附：英文原文

Title: Homogenized contact in all-perovskite tandems using tailored 2D perovskite

Author: Wang, Yurui, Lin, Renxing, Liu, Chenshuaiyu, Wang, Xiaoyu, Chosy, Cullen, Haruta, Yuki, Bui, Anh Dinh, Li, Minghui, Sun, Hongfei, Zheng, Xuntian, Luo, Haowen, Wu, Pu, Gao, Han, Sun, Wenjie, Nie, Yuefeng, Zhu, Hesheng, Zhou, Kun, Nguyen, Hieu T., Luo, Xin, Li, Ludong, Xiao, Chuanxiao, Saidaminov, Makhsud I., Stranks, Samuel D., Zhang, Lijun, Tan, Hairen

Issue&Volume: 2024-10-14

Abstract: The fabrication of scalable all-perovskite tandem solar cells is considered an attractive route to commercialize perovskite photovoltaic modules1. However, The certified efficiency of 1-cm2 scale all-perovskite tandem solar cells lags behind their small-area (~0.1 cm2) counterparts2,3. This performance deficit originates from inhomogeneity in wide-bandgap (WBG) perovskite solar cells (PSCs) at a large scale. The inhomogeneity is known to be introduced at the bottom interface and within the perovskite bulk itself4,5. Here we uncover another crucial source for the inhomogeneity – the top interface formed during the deposition of the electron transport layer (ETL, C60). Meanwhile, the poor ETL interface is also a significant limitation of device performance. We address this issue by introducing a mixture of 4-fluorophenethylamine (F-PEA) and 4-trifluoromethyl-phenylammonium (CF3-PA) to create a tailored two-dimensional perovskite layer (TTDL), in which F-PEA forms a two-dimensional perovskite at the surface reducing contact losses and inhomogeneity, CF3-PA enhances charge extraction and transport. As a result, we demonstrate a high open-circuit voltage of 1.35 V and an efficiency of 20.5% in 1.77-eV WBG PSCs at a square centimeter scale. By stacking with a narrow-bandgap perovskite sub-cell, we report 1.05 cm2 all-perovskite tandem cells delivering 28.5% (certified 28.2%) efficiency, the highest among all reported so far. Our work showcases the importance of treating the top perovskite/ETL contact for upscaling perovskite solar cells.

DOI: 10.1038/s41586-024-08158-6

Source: https://www.nature.com/articles/s41586-024-08158-6