Fabricating Perovskite Films for Solar Modules from Small to Large Scale

Abstract Perovskite solar cells (PSCs) have gained significant attention for their high efficiency, low cost, and versatile application possibilities, which are expected to play a critical role in shaping the future of photovoltaics (PV) markets. However, the power conversion efficiency (PCE) and stability of large‐area PSCs still cannot meet the industrialization requirements, which are mainly associated with the unsatisfactory quality of large‐area perovskite films. This review first identifies the factors contributing to the film quality difference between small‐area and large‐area perovskite films, such as the solvent evaporation process, reaction and crystallization kinetics, etc. This results in undesired film quality for large‐area perovskites, e.g. film inhomogeneity in terms of morphology, composition, phase, crystal size, and orientation. Solvent systems are customed for different scalable preparation process based on their volatility, solubility, and coordination ability with perovskite. Furthermore, various additives are incorporated to further regulate surface tension change and intermediate phase evolution. Finally, we transition from the perovskite film level to the device level to explore the current advancements and challenges related to PCE and stability in the commercialization process.