A Low‐Temperature, Solution‐Processable, Cu‐Doped Nickel Oxide Hole‐Transporting Layer via the Combustion Method for High‐Performance Thin‐Film Perovskite Solar Cells

Low-temperature, solution-processable Cu-doped NiOX (Cu:NiOx ), prepared via combustion chemistry, is demonstrated as an excellent hole-transporting layer (HTL) for thin-film perovskite solar cells (PVSCs). Its good crystallinity, conductivity, and hole-extraction properties enable the derived PVSC to have a high power conversion efficiency (PCE) of 17.74%. Its general applicability for various elecrode materials is also revealed.