Blade-Coated Mixed-Halide Wide-Bandgap Perovskite Photovoltaics: Progress and Challenges

Wide-bandgap (WBG) perovskite solar cells (PSC) have been widely applied in tandem photovoltaics (PV) for various scenarios including indoor, building, and underwater PV. However, the current mainstream WBG PSCs are fabricated by spin-coating, which is inappropriate for scalable production. Blade-coating has demonstrated great potential to realize commercial PV panel size at low cost, while till present, only a few efforts have been devoted to blade-coated WBG PSCs, significantly hampering their efficiency evolvements. Herein, state-of-the-art research progress and major challenges of blade-coated WBG PSCs are reviewed, with their optimization strategies being summarized into four main categories, such as blading parameter, solvent engineering, additive/dopant, and defect passivation. Film homogenization, defect manipulation, optimized blade coating machines, single-halide three-dimensional WBG perovskites, and fabrication on the textured substrate are proposed as five promising directions for future investigations on high-performance blade-coated WBG PSCs.