Effect of PbI2 passivation to grain boundary of perovskite film with cation and anion co-mixing on performance of photovoltaic devices

• Published in: Materials letters Vol. 273; p. 127979
• Main Authors: Li, Guangdong, Zou, Xiaoping, Cheng, Jin, Bai, Xiao, Chen, Dan, Yao, Yujun, Chang, Chuangchuang, Yu, Xing, Zhou, Zixiao, Wang, Junqi, Liu, Baoyu
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 15.08.2020; Elsevier BV
• Subjects: Anions; Cations; Commercialization; Crystal defects; Crystal growth; Grain boundaries; Materials science; Optoelectronic devices; Passivity; Perovskites; Photoelectricity; Photovoltaic cells; Solar cells; Solar energy materials; Thin films; X-ray techniques; Thin films; Grain boundaries; Crystal growth; X-ray techniques; Solar energy materials
• ISSN: 0167-577X; 1873-4979
• DOI: 10.1016/j.matlet.2020.127979

[Display omitted] •The PCE of FA0.3MA0.7PbI2.4Cl0.3Br0.3 perovskite solar cell fabricated by cation and anion co-mixing was improved greatly.•Moderate residual of PbI2 had a good passivation effect on the grain boundaries of FA0.3MA0.7PbI2.4Cl0.3Br0.3 film.•Moderate residual of PbI2 was attributed to the component adjustment of perovskite layer by co-mixing. Perovskite components have tremendous influence on the film quality and device performance. There are obvious impurity defects, holes, etc. in the films of conventional perovskite solar cells (PSCs). In this work, the perovskite component was tuned to [HC(NH2)2]0.3(CH3NH3)0.7PbI2.4Cl0.3Br0.3 (FA0.3MA0.7PbI2.4Cl0.3Br0.3) via cation and anion co-mixing, it was observed that the residual PbI2 at perovskite film had a good passivation effect on the grain boundaries and further ameliorated the quality of the film. The photoelectric conversion efficiency (PCE) of low-cost carbon electrode-based photovoltaic devices we prepared increased from 8.58% to 12.40%. Our work will also be more beneficial to the commercialization of PSCs and the preparation of other optoelectronic devices.