Publication Date: October 15, 2025
On October 15, 2025, Professor Yabing Qi from the Pu Yuan Future Technology Institute/Zhangjiang Advanced Research Institute of Shanghai Jiao Tong University, collaborating with Associate Researcher Jia Liang from the Institute of Intelligent Materials and Future Energy Innovation/State Key Laboratory of Photovoltaic Science and Technology of Fudan University and Professor Bo Xu from the School of Chemistry and Chemical Engineering of Nanjing University of Science and Technology, achieved a major original breakthrough in the field of lead-free perovskite solar cells. The relevant research results were published online in the top international academic journal Nature under the title "Tin-based perovskite solar cells with a homogeneous buried interface", providing a core solution for the industrial development of high-efficiency and stable lead-free photovoltaic devices.
Figure 1. "Dual-Hole Transport Layer" Inducing High-Quality Tin-Based Perovskite Films
The study proposes an ingenious "dual-hole transport layer" structure. This structure uses nickel oxide (NiOx) with excellent stability as the bottom substrate, and a self-assembled monolayer (SAM) is constructed on it, thereby forming a uniform and functionally synergistic composite functional layer. This composite functional layer is like a "tailor-made" growth template for tin-based perovskites: on the one hand, it greatly improves the spreading ability of tin-based perovskite solutions on the surface, guiding the formation of high-quality, low-defect tin-based perovskite films; on the other hand, it possesses excellent hole extraction and interface passivation capabilities, enabling more efficient output of photogenerated current. The research provides a new interface engineering paradigm and universal method for the high-efficiency and stable design of lead-free perovskite solar cells.
Perovskite solar cells have emerged as a research hotspot in the photovoltaic field due to their high conversion efficiency. However, traditional lead-based perovskites pose a risk of heavy metal leakage, which severely restricts their application. Tin-based perovskite solar cells (TPSCs) serve as an ideal lead-free alternative, with a theoretical power conversion efficiency (PCE) of up to 33% and environmentally friendly properties, making them a crucial direction for next-generation photovoltaic technology. Nevertheless, the performance of tin-based perovskite devices has long lagged behind that of lead-based counterparts: on one hand, existing hole transport layers struggle to extract holes efficiently; on the other hand, uneven buried interfaces result in poor crystallization quality, high defect density of perovskite films, and severe non-radiative recombination losses. Previously, the certified efficiency of inverted-structured tin-based perovskites was approximately 16%, and their relatively poor stability, in particular, fails to meet the requirements of practical applications, becoming a key bottleneck hindering their industrialization.
To address the aforementioned challenges, the research team innovatively designed a novel molecule MBP and applied it to the buried interface modification of the NiOx hole transport layer, constructing a dual optimization system consisting of a "uniform interface layer + super-wettable underlayer".
MBP can form an ultra-flat molecular layer on the NiOx surface with a surface roughness of only 1.87 nm, which is much lower than 6.04 nm of the traditional modifying molecule 2PACz. It not only effectively solves the problem of uneven substrate coverage of traditional molecules, but also significantly improves the hole extraction efficiency by optimizing energy level matching. Based on this optimized system, the power conversion efficiency (PCE) of small-area (0.04 cm²) TPSCs reaches 17.89%, with a certified efficiency of 17.71%, setting a new record for the highest efficiency of tin-based perovskite solar cells to date.
The stability of the device has also achieved a significant breakthrough, maintaining over 95% and 94% of its efficiency under 1344 hours of ambient storage and 1550 hours of continuous illumination, respectively. In addition, this technological breakthrough is not confined to the laboratory level; the team simultaneously conducted research on large-area battery fabrication and scalability. The efficiency of 1 cm² large-area TPSCs reached 14.40%, the highest value reported so far, fully demonstrating the excellent scalability and uniformity of this technology.
Figure 2. Photovoltaic conversion performance of the tin-based perovskite solar cells in this research work.
Tianpeng Li, a doctoral student at Fudan University, is the first author of the paper. Professor Qi Yabing from Pu Yuan Future Technology College/Zhangjiang Institute for Advanced Study of Shanghai Jiao Tong University, Young Researcher Liang Jia from Fudan University, and Professor Xu Bo from Nanjing University of Science and Technology are the co-corresponding authors. Other collaborating institutions include Tongji University and Donghua University, etc. This research work was supported by projects from Pu Yuan Future Technology College of Shanghai Jiao Tong University, Zhangjiang Institute for Advanced Study of Shanghai Jiao Tong University, Fudan University, Nanjing University of Science and Technology, and the National Natural Science Foundation of China.
Original Paper Link:https://doi.org/10.1038/s41586-025-09724-2
