Chen Zicong, Yang Zhenyu, Du Shijie, Lin Dabin, Zhang Fangteng, Zeng Youjun, Liu Guanyu, Nie Zhaogang, Ma Lin
School of Physics and Optoelectronic Engineering, Guangdong University of Technology, Guangzhou 510006, China.
School of Physical Science and Information Technology, Liaocheng University, Liaocheng 252059, China.
Phys Chem Chem Phys. 2023 Dec 13;25(48):32966-32971. doi: 10.1039/d3cp03704e.
Organic-inorganic halide perovskites (OIHPs) have emerged as one of the most efficient photovoltaic materials due to their superior properties. However, improving their stability remains a key challenge. Herein, we investigate the thermal decomposition properties of OIHP FAMAPbI with mixed cations of formamidinium (FA) and methylammonium (MA). Using thermogravimetric analysis together with Fourier transform infrared spectroscopy, we identify and monitor the gaseous decomposition products as a function of temperature and cation composition. Thermal decomposition products of both MA and FA cations were observed at all stages of the thermal decomposition process, contrary to previous expectations. The yield, release sequence and kinetics of the organic gaseous products were found to depend strongly on the ratio between FA and MA cations. Furthermore, cesium ion doping was investigated as a potential strategy to improve the thermal stability of mixed cation perovskites. These results provide new insights into the effect of cation mixing on perovskite stability, suggesting that optimizing the cation ratios and decomposition pathways can guide approaches to boost the stability and performance of mixed cation perovskites.
有机-无机卤化物钙钛矿（OIHPs）因其优异的性能已成为最有效的光伏材料之一。然而，提高其稳定性仍然是一个关键挑战。在此，我们研究了具有甲脒（FA）和甲基铵（MA）混合阳离子的OIHP FAMAPbI的热分解特性。通过热重分析结合傅里叶变换红外光谱，我们识别并监测了气态分解产物随温度和阳离子组成的变化。与先前的预期相反，在热分解过程的所有阶段都观察到了MA和FA阳离子的热分解产物。发现有机气态产物的产率、释放顺序和动力学强烈依赖于FA和MA阳离子之间的比例。此外，研究了铯离子掺杂作为提高混合阳离子钙钛矿热稳定性的潜在策略。这些结果为阳离子混合对钙钛矿稳定性的影响提供了新的见解，表明优化阳离子比例和分解途径可以指导提高混合阳离子钙钛矿稳定性和性能的方法。
