Mei Yantao, Lu Xiayao, Dong Chen, Tan Furui, Cui Minghuan, Haruta Yuki, Yeddu Vishal, Wang Mengyue, Liu Kong, Yue Gentian, Gao Yueyue, Qu Shengchun, Qin Chaochao, Zhang Weifeng, Ding Liming, Saidaminov Makhsud I, Wang Zhijie
Key Laboratory of Photovoltaic Materials, Henan University, Kaifeng 475004, P. R. China.
Henan Key Laboratory of Infrared Materials & Spectrum Measures and Applications, Henan Normal University, Xinxiang 453007, P. R. China.
ACS Appl Mater Interfaces. 2022 Aug 31;14(34):38963-38971. doi: 10.1021/acsami.2c11895. Epub 2022 Aug 17.
Carbon-based all-inorganic CsPbIBr perovskite solar cells offer high stability against heat and humidity and a suitable band gap for tandem and semitransparent photovoltaics. In CsPbIBr perovskite films, the defects at grain boundaries (GBs) cause charge trapping, reducing the efficiency of the cell. Electronic deactivation of GB has been a conventional strategy to suppress the trapping, but at the cost of charge carrier transport through the boundaries. Here, we turn the GBs into benign charge transport pathways with the aid of bipolar charge transport semiconductors, namely, TiCT (MXene) and Spiro-OMeTAD, respectively. Thanks to the synergistic effects of both n- and p-type transport media, the charge transport is improved and balanced at the GBs. As a result, the cells achieve an efficiency of 12.7%, the highest among all low-temperature-processed carbon-based inorganic perovskite solar cells. Benign GBs also lead to enhanced light and aging stabilities. Our work demonstrates a proof-of-concept strategy of benign electronic modulation of GBs for solution-processed perovskite solar cells.
碳基全无机CsPbIBr钙钛矿太阳能电池具有高的耐热和耐湿性，并且具有适合用于串联和半透明光伏的带隙。在CsPbIBr钙钛矿薄膜中，晶界（GBs）处的缺陷会导致电荷俘获，从而降低电池效率。对晶界进行电子钝化一直是抑制俘获的传统策略，但代价是电荷载流子通过晶界的传输。在此，我们分别借助双极电荷传输半导体TiCT（MXene）和Spiro-OMeTAD，将晶界转变为良性电荷传输通道。由于n型和p型传输介质的协同效应，电荷传输在晶界处得到改善并实现平衡。结果，这些电池实现了12.7%的效率，这在所有低温处理的碳基无机钙钛矿太阳能电池中是最高的。良性晶界还导致光稳定性和老化稳定性增强。我们的工作展示了一种用于溶液处理的钙钛矿太阳能电池的晶界良性电子调制的概念验证策略。
