Fu Sheng, Sun Nannan, Chen Hao, Liu Cheng, Wang Xiaoming, Li You, Abudulimu Abasi, Xu Yuanze, Ramakrishnan Shipathi, Li Chongwen, Yang Yi, Wan Haoyue, Huang Zixu, Xian Yeming, Yin Yifan, Zhu Tingting, Chen Haoran, Rahimi Amirhossein, Saeed Muhammad Mohsin, Zhang Yugang, Yu Qiuming, Ginger David S, Ellingson Randy J, Chen Bin, Song Zhaoning, Kanatzidis Mercouri G, Sargent Edward H, Yan Yanfa
Department of Physics and Astronomy and Wright Center for Photovoltaics Innovation and Commercialization, University of Toledo, Toledo, OH, USA.
Department of Chemistry, Northwestern University, Evanston, IL, USA.
Nat Nanotechnol. 2025 Apr 17. doi: 10.1038/s41565-025-01900-9.
In the fabrication of FAPbI-based perovskite solar cells, Lewis bases play a crucial role in facilitating the formation of the desired photovoltaic α-phase. However, an inherent contradiction exists in their role: they must strongly bind to stabilize the intermediate δ-phase, yet weakly bind for rapid removal to enable phase transition and grain growth. To resolve this conflict, we introduced an on-demand Lewis base molecule formation strategy. This approach utilized Lewis-acid-containing organic salts as synthesis additives, which deprotonated to generate Lewis bases precisely when needed and could be reprotonated back to salts for rapid removal once their role is fulfilled. This method promoted the optimal crystallization of α-phase FAPbI perovskite films, ensuring the uniform vertical distribution of A-site cations, larger grain sizes and fewer voids at buried interfaces. Perovskite solar cells incorporating semicarbazide hydrochloride achieved an efficiency of 26.1%, with a National Renewable Energy Laboratory-certified quasi-steady-state efficiency of 25.33%. These cells retained 96% of their initial efficiency after 1,000 h of operation at 85 °C under maximum power point tracking. Additionally, mini-modules with an aperture area of 11.52 cm reached an efficiency of 21.47%. This strategy is broadly applicable to all Lewis-acid-containing organic salts with low acid dissociation constants and offers a universal approach to enhance the performance of perovskite solar cells and modules.
在基于FAPbI的钙钛矿太阳能电池制造中，路易斯碱在促进所需光伏α相的形成方面起着关键作用。然而，它们的作用存在一个内在矛盾：它们必须强烈结合以稳定中间δ相，但又要弱结合以便快速去除，从而实现相变和晶粒生长。为了解决这一冲突，我们引入了一种按需形成路易斯碱分子的策略。该方法利用含路易斯酸的有机盐作为合成添加剂，这些添加剂在需要时去质子化生成路易斯碱，一旦其作用完成，又可以重新质子化变回盐以便快速去除。这种方法促进了α相FAPbI钙钛矿薄膜的最佳结晶，确保了A位阳离子的均匀垂直分布、更大的晶粒尺寸以及掩埋界面处更少的空隙。掺入盐酸氨基脲的钙钛矿太阳能电池效率达到26.1%，经美国国家可再生能源实验室认证的准稳态效率为25.33%。这些电池在85°C最大功率点跟踪下运行1000小时后，仍保留其初始效率的96%。此外，孔径面积为11.52平方厘米的微型模块效率达到21.47%。该策略广泛适用于所有酸解离常数低的含路易斯酸有机盐，并提供了一种提高钙钛矿太阳能电池和模块性能的通用方法。
