Wu Guohua, Li Hua, Cui Jian, Zhang Yaohong, Olthof Selina, Chen Shuai, Liu Zhike, Wang Dapeng, Liu Shengzhong Frank
Key Laboratory of Applied Surface and Colloid Chemistry National Ministry of Education Shaanxi Key Laboratory for Advanced Energy Devices Shaanxi Engineering Laboratory for Advanced Energy Technology School of Materials Science and Engineering Shaanxi Normal University Xi'an 710119 China.
Faculty of Informatics and Engineering The University of Electro-Communications 1-5-1 Chofugaoka, Chofu Tokyo 182-8585 Japan.
Adv Sci (Weinh). 2020 Mar 10;7(10):1903250. doi: 10.1002/advs.201903250. eCollection 2020 May.
A strategy for efficaciously regulating perovskite crystallinity is proposed by using a volatile solid glycolic acid (HOCHCOOH, GA) in an FAMAPbI (FA: HC(NH); MA: CHNH) perovskite precursor solution that is different from the common additive approach. Accompanied with the first dimethyl sulfoxide sublimation process, the subsequent sublimation of GA before 150 °C in the FAMAPbI perovskite film can artfully regulate the perovskite crystallinity without any residual after annealing. The improved film formation upon GA modification induced by the strong interaction between GA and Pb delivers a champion power conversion efficiency (PCE) as high as 21.32%. In order to investigate the role of volatility in perovskite solar cells (PSCs), nonvolatile thioglycolic acid (HSCHCOOH, TGA) with a similar structure to GA is utilized as an additive reference. Large perovskite grains are obtained by TGA modification but with obvious pinholes, which directly leads to an increased defect density accompanied by a decline in PCE. Encouragingly, the champion PCE achieved for GA-based PSC device (21.32%) is almost 13% or 20% higher than those of the control device or TGA-based device. In addition, GA-modified PSCs exhibit the best stability in light-, thermal-, and humidity-based tests due to the improved film formation.
通过在FAMAPbI（FA：HC(NH)；MA：CHNH）钙钛矿前驱体溶液中使用挥发性固体乙醇酸（HOCH₂COOH，GA），提出了一种有效调节钙钛矿结晶度的策略，这与常见的添加剂方法不同。伴随着第一次二甲基亚砜升华过程，GA在150℃之前于FAMAPbI钙钛矿薄膜中随后的升华可以巧妙地调节钙钛矿结晶度，退火后无任何残留。GA与Pb之间的强相互作用诱导的GA修饰后改善的成膜，带来了高达21.32%的冠军功率转换效率（PCE）。为了研究挥发性在钙钛矿太阳能电池（PSC）中的作用，具有与GA相似结构的非挥发性硫代乙醇酸（HSCH₂COOH，TGA）被用作添加剂参考。通过TGA修饰获得了大的钙钛矿晶粒，但有明显的针孔，这直接导致缺陷密度增加，同时PCE下降。令人鼓舞的是，基于GA的PSC器件实现的冠军PCE（21.32%）比对照器件或基于TGA的器件高出近13%或20%。此外，由于成膜得到改善，GA修饰的PSC在基于光、热和湿度的测试中表现出最佳的稳定性。
