https://en.people.cn/n3/2025/1016/c90000-20378055.html

https://www.nature.com/articles/s41586-025-09724-2

Perovskite solar cells have been hailed as a potential game-changer for their high efficiency and low production costs, but their reliance on toxic lead has raised concerns about large-scale deployment. A team led by Fudan University has now developed a lead-free, tin-based alternative,  that achieved a  power conversion efficiency of 17.7 percent, the highest known level for such cells to date.

Since tin ions oxidize easily and the interface between layers tends to be unstable, early tin-based cells struggled to reach 10 percent efficiency. The team redesigned the buried interface by introducing a molecular film to form a homogeneous interfacial layer with well-matched energy level alignment. This approach helped create a “superwetting” underlayer that guides the growth of uniform, high-quality tin-based perovskite films with reduced defect density.

In terms of material cost, tin-based solar cells are cheaper than their silicon counterparts. It is expected that this green photovoltaic technology is expected to be widely deployed in building-integrated photovoltaics, wearable energy devices, vehicle rooftops, and off-grid clean-power systems.