Abstract
Wide-bandgap (WBG) perovskite solar cells possess huge potential for integration into next-generation heterojunction photovoltaic systems. Conversely, their well-known commercialization is presently hindered by several challenges, including considerable open circuit voltage losses and poor long-term stability. Here, we report phenylhydrazinium chloride (PCl) as an effective dopant in WBG CsPbIBr(2) perovskite solar cells, which inhibits halide oxidation and demixing in addition to decreasing defect density, leading to highly crystalline perovskite films. As a result of lower defects, PSCs obtained by PCl WBG CsPbIBr(2) achieved a PCE of 10.83%, possessing a V (oc) of 1.24 and an enhanced stability of more than 300 h. This work may deliver a viable solution toward the fabrication of WBG CsPbIBr(2) PSCs sub-cells for tandem solar cells.