Core Insights - The research team at the Qingdao Institute of Bioenergy and Process Research has developed a new mechanism to control metal ion migration in copper zinc tin sulfur selenium (CZTSSe) photovoltaic materials, leading to a breakthrough in solar cell efficiency [1][2] - The photovoltaic conversion efficiency of CZTSSe solar cells has surpassed 15%, marking a significant advancement in China's research on next-generation solar cells [1] Group 1 - The new mechanism involves introducing a Li2SnS3 interface phase that guides metal ions during the phase transition process, resulting in more uniform and stable crystal structures [1] - The efficiency of the developed CZTSSe solar cells reached 15.45%, with an internationally certified efficiency of 15.04% [2] - The open-circuit voltage has exceeded 600 millivolts under narrow bandgap conditions, providing a new approach to overcoming performance bottlenecks in this type of photovoltaic device [2] Group 2 - CZTSSe materials are gaining attention in the photovoltaic field due to their abundant elemental reserves, low cost, high stability, and non-toxicity [1] - The research findings have significant implications for the industrialization process of CZTSSe solar cells, offering crucial theoretical and technical support [2]