上海交通大学赵一新团队报道了高效钙钛矿子模块的杂质修复界面工程。相关研究成果于2024年9月26日发表于国际顶尖学术期刊《自然》。

一个始终阻碍钙钛矿光伏技术大规模发展的问题是，当扩大器件面积时，效率会显著下降，这是由缺陷位点的不均匀分布引起的。在窄带隙甲脒碘化铅（FAPbI₃）中，PbI₂和δ-FAPbI₃非钙钛矿的天然杂质可能会引起不利的非辐射复合，以及较差的电荷传输和提取。

该文中，研究人员开发了一种杂质修复界面工程策略，以很好地解决小面积太阳能电池和大型子模块中的问题。通过引入功能阳离子2-（1-环己烯基）乙基铵，在FAPbI₃上合理构建了具有高迁移率的二维（2D）钙钛矿，以水平覆盖薄膜表面并垂直渗透到3D钙钛矿的晶界。

这种独特的结构不仅将PbI₂和δ-FAPbI₃杂质全面转化为稳定的二维钙钛矿，实现了均匀的缺陷钝化，还为高效的载流子传输提供了互连通道。因此，基于FAPbI₃的小面积（0.085cm²）太阳能电池实现了超过25.86%的最高效率，填充因子（FF）显著高达86.16%。

更令人鼓舞的是，孔径面积为715.1 cm²的预制子模块获得了22.46%的认证记录效率和81.21%的良好FF，展示了杂质修复界面工程在保持良好光伏性能的情况下，扩大推广的可行性和有效性。

附：英文原文

Title: Impurity-healing interface engineering for efficient perovskite submodules

Author: Wang, Haifei, Su, Shuojian, Chen, Yuetian, Ren, Meng, Wang, Shaowei, Wang, Yao, Zhu, Chen, Miao, Yanfeng, Ouyang, Chuying, Zhao, Yixin

Issue&Volume: 2024-09-26

Abstract: One issue that always strands the scaling-up development of perovskite photovoltaics is the significant efficiency drop when enlarging the device area, which is caused by the inhomogeneous distribution of defected sites1-3. In the narrow band gap formamidinium lead iodide (FAPbI3), the native impurities of PbI2 and δ-FAPbI3 non-perovskite could induce unfavored non-radiative recombination, as well as inferior charge transport and extraction 4,5.Here, we develop an impurity-healing interface engineering strategy to well address the issue both in small-area solar cell and large-scale submodule. With the introduction of a functional cation, 2-(1-cyclohexenyl)ethyl ammonium, two-dimensional (2D) perovskite with high mobility is rationally constructed on FAPbI3 to horizontally cover the film surface and vertically penetrate to the grain boundaries of 3D perovskites. Such unique configuration not only comprehensively transforms the PbI2 and δ-FAPbI3 impurities into stable 2D perovskite and realize a uniform defect passivation, but also provides interconnecting channels for efficient carrier transport. As a result, the FAPbI3-based small-area (0.085 cm2) solar cells achieve a champion efficiency over 25.86% with a notably high fill factor (FF) of 86.16%. More encouragingly, the fabricated submodules with the aperture area of 715.1 cm2 obtain a certified record efficiency of 22.46% with a good FF of 81.21%, showcasing the feasibility and effectualness of the impurity-healing interface engineering for scaling-up promotion with well-preserved photovoltaic performance.

DOI: 10.1038/s41586-024-08073-w

Source: https://www.nature.com/articles/s41586-024-08073-w