110225-28-0Relevant articles and documents
Halogen-halogen bonds enable improved long-term operational stability of mixed-halide perovskite photovoltaics
Fu, Xinliang,He, Tingwei,Hsu, Hsien-Yi,Jiang, Yuanzhi,Lei, Xiaojuan,Li, Xiaofang,Sun, Pingchuan,Wang, Di,Wang, Mei,Yuan, Mingjian,Zhang, Shifu,Zhao, Dongbing
supporting information, p. 3131 - 3143 (2021/11/16)
Mixed-halide perovskite provides band-gap tunability, which is essential for tandem solar cell application. However, ion migration inducing phase segregation seriously affects the device's long-term operational stability. The issue thus represents an important challenge for the whole perovskite community and urgently needs effective solutions. We showcase here for the first time that a strong chemical interaction, a halogen-halogen bond, is introduced at the phase interface to suppress the ion migration by increasing the corresponding activation energy. Various characterizations have proved that halogen-halogen bonds form between 2D and 3D phases, which do suppress the halide segregation. As expected, the encapsulated device retains 90% of initial power conversion efficiency (PCE) after maximum power point (MPP) tracking for ~500 h under continuous simulated 1-sun illumination (AM 1.5) in ambient conditions, representing one of the most stable, wide-band-gap, mixed-halide perovskite photovoltaics reported so far.