Minimizing Photovoltage Loss for Efficient p–i–n Perovskite Solar Cells via a Dual‐Site Anchoring Bridge
Xiaoyun Wan, Shaobing Xiong, Hao Wang, Kai Jiang, Zhennan Lin, Di Li, Jinyang Yu, Bin Zhao, Jiyuan Chen, Songjie Zhou, Lixuan Kan, Bo Li, Yu‐Ning Wu, Ye‐Feng Yao, Yanbo Wang, Haiming Zhu, Zhenrong Sun, Junhao Chu, Qinye Bao
Abstract
Perovskite solar cells (PSCs) suffer from severe nonradiative recombination-induced photovoltage loss, limiting the device overall performance. To address this key issue, an efficient strategy via a dual-site anchoring bridge is developed to engineer the heterointerface between perovskite and PCBM electron transport layer. The resulting reinforced and homogeneous passivation by forming strong dual-site P─O─Pb covalent bonds, effectively decreases perovskite surface defect density. This simultaneously reconstructs surface energetics of perovskite with upshifted Fermi level and enhanced electric field, promoting electron extraction at the perovskite/PCBM heterointerface. Corresponding nonradiative recombination at such perovskite electron-selective contact is greatly suppressed. An impressive power conversion efficiency of 26.3% is obtained with excellent stability under continuous maximum power point operation, and a supreme photovoltage of 1.215 V in p-i-n PSCs via interfacial engineering reported so far. This work offers a promising strategy for solving the perovskite contact challenge via innovative modifier for further improvement of PSCs.