Self-assembled materials with an ordered hydrophilic bilayer for high performance inverted Perovskite solar cells
Geping Qu, Letian Zhang, Ying Qiao, Shaokuan Gong, Yuanjia Ding, Yuli Tao, Siyuan Cai, Xiaoyong Chang, Qian Chen, Pengfei Xie, Junyuan Feng, Changqin Gao, Guopeng Li, Hui Xiao, Fei Wang, Hanlin Hu, Jie Yang, Chen Shi, Alex K.‐Y. Jen, Xihan Chen, Zong‐Xiang Xu
Abstract
While self-assembled material based inverted perovskite solar cells have surpassed power conversion efficiencies of 26%, enhancing their performance in large-area configurations remains a significant challenge. In this work, we report a self-assembled material based hole-selective layer 4-(7H-dibenzo[c,g]carbazol-7-yl)phenyl)phosphonic acid, with a π-expanded conjugation. The enhanced intermolecular π–π interactions facilitate the self-assembly of 4-(7H-dibenzo[c,g]carbazol-7-yl)phenyl)phosphonic acid molecules to form an ordered bilayer with a hydrophilic surface, which passivates the buried perovskite interface defect and enables high-quality and large-area perovskite preparation, while simultaneously enhancing interfacial charge extraction and transport. The certified efficiency of 4-(7H-dibenzo[c,g]carbazol-7-yl)phenyl)phosphonic acid based small-area (0.0715 cm2) device is 26.39% with high stability. Furthermore, a certified efficiency of 25.21% is achieved for a 99.12 mm2 large area device. Qu et al. report a self-assembled material with π-expanded conjugation to form hydrophilic ordered bilayer as hole selective layer for inverted perovskite solar cells. The enhanced interfacial charge extraction and transport enable certified efficiency of 26.39% and 25.21% for 7.15 mm2 - and 99.12 mm2 -devices, respectively.