All-perovskite tandem solar cells, which integrate the benefits of high efficiency and low cost, are a significant avenue for the advancement of next-generation photovoltaic technology. The research team, headed by Professor Lin Renxing and Tan Hairen from Nanjing University, has achieved a remarkable breakthrough in this area. Their developed all-perovskite tandem cell has attained a conversion efficiency of up to 30.1%, a figure verified by the internationally recognized JET (which could stand for a specific certification body; if not, you may need to provide the full name for clarity). This achievement represents the inaugural instance where the efficiency of polycrystalline thin-film solar cells has exceeded 30%. The pertinent findings have been incorporated. This research accomplishment has been published online in the leading journal (you may need to specify the journal's name) in the form of a rapid preview. Nanjing University serves as the first author and corresponding institution, with Lin Renxing and others acting as co-first authors and corresponding authors. The paper link is provided below (or "attached" if it's literally attached in some document format).