Performance promotion strategies for wide bandgap perovskite solar cells

Abstract

Wide bandgap (WBG) perovskites, with an adjustable bandgap and easy solution fabrication process, are prime candidates for top sub-cells in tandem solar cells (TSCs). Their successful integration with narrow bandgap devices has inspired the rapid development of perovskite-based TSCs and has become one of the most promising technologies in photovoltaics. However, several tough issues related to WBG PSCs, such as open-circuit voltage (V_OC) loss and phase separation, impede their further improvement in device efficiency and stability. Hence, through a systematic review on the development of WBG PSCs, the critical problems such as defects, phase segregation, and strain are discussed, and effective solution strategies, including passivation, additive engineering, composition engineering and interface engineering with self-assembled monolayers (SAM) are summarized. This comprehensive review is expected to provide guidance for designing and developing more effective WBG devices.