Chen Liang, Tan Yan-Yan, Chen Zhi-Xin, Wang Tan, Hu Shu, Nan Zi-Ang, Xie Li-Qiang, Hui Yong, Huang Jing-Xin, Zhan Chao, Wang Su-Heng, Zhou Jian-Zhang, Yan Jia-Wei, Mao Bing-Wei, Tian Zhong-Qun
State Key Laboratory of Physical Chemistry of Solid Surfaces, Department of Chemistry, College of Chemistry and Chemical Engineering, and Collaborative Innovation Center of Chemistry for Energy Materials , Xiamen University , Xiamen 361005 , China.
J Am Chem Soc. 2019 Jan 30;141(4):1665-1671. doi: 10.1021/jacs.8b11610. Epub 2019 Jan 16.
Perovskite solar cells are strong competitors for silicon-based ones, but suffer from poor long-term stability, for which the intrinsic stability of perovskite materials is of primary concern. Herein, we prepared a series of well-defined cesium-containing mixed cation and mixed halide perovskite single-crystal alloys, which enabled systematic investigations on their structural stabilities against light, heat, water, and oxygen. Two potential phase separation processes are evidenced for the alloys as the cesium content increases to 10% and/or bromide to 15%. Eventually, a highly stable new composition, (FAPbI)(MAPbBr)(CsPbBr), emerges with a carrier lifetime of 16 μs. It remains stable during at least 10 000 h water-oxygen and 1000 h light stability tests, which is very promising for long-term stable devices with high efficiency. The mechanism for the enhanced stability is elucidated through detailed single-crystal structure analysis. Our work provides a single-crystal-based paradigm for stability investigation, leading to the discovery of stable new perovskite materials.
钙钛矿太阳能电池是硅基太阳能电池的有力竞争者，但长期稳定性较差，因此钙钛矿材料的固有稳定性是首要关注的问题。在此，我们制备了一系列结构明确的含铯混合阳离子和混合卤化物钙钛矿单晶合金，这使得我们能够系统地研究它们在光、热、水和氧气作用下的结构稳定性。随着铯含量增加到10%和/或溴化物含量增加到15%，合金出现了两种潜在的相分离过程。最终，一种高度稳定的新成分(FAPbI)(MAPbBr)(CsPbBr)出现，其载流子寿命为16微秒。在至少10000小时的水氧和1000小时的光稳定性测试中，它保持稳定，这对于高效的长期稳定器件非常有前景。通过详细的单晶结构分析阐明了稳定性增强的机制。我们的工作为稳定性研究提供了一种基于单晶的范例，从而发现了稳定的新型钙钛矿材料。
