Homogeneity Regulation in Sequential Fabricated Perovskite Film for Industrial‐Scale Deposition of Fully‐Textured Perovskite/Silicon Tandem Cells

Abstract The combination of industrially crystalline silicon with metal halide perovskites in a tandem configuration has been the focus of intense research efforts. Although a hybrid deposition method has been developed to achieve conformal and scalable growth of perovskite film on textured silicon, this dry/wet approach faces problems of incomplete reaction and phase impurities, posing a challenge for up‐scaling fabrication. Herein, a synergistic strategy is demonstrated for homogeneity regulation of penetration of organic salts by employing solvent engineering in slot‐die coating combined with near‐infrared (NIR) irradiation pre‐heating. The use of mixed solvent contributes to a phase‐pure and homogeneous perovskite film by balancing the rate of solvent evaporation and reactant diffusion. Additionally, the NIR energy heats the large‐area perovskite wet film directly and rapidly in the air, and thus controls the solvent volatilization for uniform phase transformation. As a result, this strategy enables the air‐processed perovskite‐silicon tandem device based on an industrial c‐Si cell to achieve an efficiency of 30.95% (certified 30.6%) for an active area of 1.0 cm 2 and obtain an efficiency of 27.1% for an aperture area of 110 cm 2 . Furthermore, the encapsulated large‐area device retains 89% of the initial output after 1100 h of maximum power point tracking.