Lv Yifan, Zhang Hui, Wang Jinpei, Chen Libao, Bian Lifang, An Zhongfu, Qian Zongyao, Ren Guoqi, Wu Jie, Nüesch Frank, Huang Wei
Key Laboratory of Flexible Electronics (KLOFE) and Institute of Advanced Materials (IAM), Jiangsu National Synergetic Innovation Center for Advanced Materials (SICAM), Nanjing Tech University (NanjingTech), 5 Xinmofan Road, Nanjing 210009, China.
Empa, Swiss Federal Institute for Materials Science and Technology, Laboratory for Functional Polymers, Dübendorf CH-8600, Switzerland.
Research (Wash D C). 2020 Oct 14;2020:2763409. doi: 10.34133/2020/2763409. eCollection 2020.
Nonradiative recombination losses originating from crystallographic distortions and issues occurring upon interface formation are detrimental for the photovoltaic performance of perovskite solar cells. Herein, we incorporated a series of carbamide molecules (urea, biuret, or triuret) consisting of both Lewis base (-NH) and Lewis acid (-C=O) groups into the perovskite precursor to simultaneously eliminate the bulk and interface defects. Depending on the different coordination ability with perovskite component, the incorporated molecules can either modify crystallization dynamics allowing for large crystal growth at low temperature (60°C), associate with antisite or undercoordinated ions for defect passivation, or accumulate at the surface as an energy cascade layer to enhance charge transfer, respectively. Synergistic benefits of the above functions can be obtained by rationally optimizing additive combinations in an all-in-one deposition method. As a result, a champion efficiency of 21.6% with prolonged operational stability was achieved in an inverted MAPbI perovskite solar cell by combining biuret and triuret additives. The simplified all-in-one fabrication procedure, adaptable to different types of perovskites in terms of pure MAPbI, mixed perovskite, and all-inorganic perovskite, provides a cost-efficient and reproducible way to obtain high-performance inverted perovskite solar cells.
由晶体学畸变引起的非辐射复合损失以及界面形成时出现的问题对钙钛矿太阳能电池的光伏性能不利。在此，我们将一系列由路易斯碱（-NH）和路易斯酸（-C=O）基团组成的尿素分子（尿素、缩二脲或三聚脲）引入钙钛矿前驱体中，以同时消除体相和界面缺陷。根据与钙钛矿组分不同的配位能力，引入的分子既可以改变结晶动力学，使得在低温（60°C）下能够生长出大晶体，与反位或配位不足的离子结合以钝化缺陷，也可以在表面聚集形成能量级联层以增强电荷转移。通过在一体化沉积方法中合理优化添加剂组合，可以获得上述功能的协同效益。结果，通过组合使用缩二脲和三聚脲添加剂，在倒置的MAPbI钙钛矿太阳能电池中实现了21.6%的最高效率以及延长的运行稳定性。简化的一体化制造工艺适用于纯MAPbI、混合钙钛矿和全无机钙钛矿等不同类型的钙钛矿，为获得高性能倒置钙钛矿太阳能电池提供了一种经济高效且可重复的方法。
