The article by Tomoya Nakamura et al. reviews the advancements in materials chemistry for improving the performance of metal halide perovskite photovoltaics. The authors highlight the development of high-purity precursor materials and precursor inks, which are crucial for reliable fabrication of high-quality perovskite films. They also discuss the importance of nucleation and crystallization processes, supported by numerical simulations, to achieve dense and flat perovskite films. Additionally, the article covers the introduction of new charge collection materials and surface passivation compounds to enhance solar cell performance. The authors emphasize the role of materials chemistry in advancing perovskite photovoltaics, including the development of lead-free tin-based perovskites and the use of antisolvent treatment to improve film quality. The article concludes with a discussion on the future prospects of perovskite photovoltaics, highlighting the potential for practical applications in a carbon-neutral society.The article by Tomoya Nakamura et al. reviews the advancements in materials chemistry for improving the performance of metal halide perovskite photovoltaics. The authors highlight the development of high-purity precursor materials and precursor inks, which are crucial for reliable fabrication of high-quality perovskite films. They also discuss the importance of nucleation and crystallization processes, supported by numerical simulations, to achieve dense and flat perovskite films. Additionally, the article covers the introduction of new charge collection materials and surface passivation compounds to enhance solar cell performance. The authors emphasize the role of materials chemistry in advancing perovskite photovoltaics, including the development of lead-free tin-based perovskites and the use of antisolvent treatment to improve film quality. The article concludes with a discussion on the future prospects of perovskite photovoltaics, highlighting the potential for practical applications in a carbon-neutral society.