Lattice stabilization and strain homogenization in Sn-Pb bottom subcells enable stable all-perovskite tandems solar cells

作者：Yang Bai, Yuanyuan Meng, Ming Yang, Ruijia Tian, Jingnan Wang, Boxin Jiao, Haibin Pan, Jiangwei Gao, Yaohua Wang, Kexuan Sun, Shujing Zhou, Xiaoyi Lü, Zhenhua Song, Chang Liu, Ziyi Ge · 发表于：Nature Communications · 年份：2025 · DOI：10.1038/s41467-025-62661-6 · 被引用次数：26 · 研究领域：Perovskite Materials and Applications、Chalcogenide Semiconductor Thin Films、Organic Electronics and Photovoltaics

All-perovskite tandem solar cells (PTSCs) offer a promising approach to surpass the Shockley-Queisser (SQ) limit, driven by efficiently reducing thermalization and transmission losses. However, the efficiency and stability of the narrow-bandgap (NBG) subcells, which are essential for PTSC performance, remain severely constrained by challenges such as lattice instability, strain accumulation and halide migration under illumination. This study introduces a rigid sulfonate-based molecule, sodium naphthalene-1,3,6-trisulfonate (NTS), into tin-lead (Sn-Pb) perovskites, where it strengthens the Sn-I bond through Sn-trisulfonate coordination and reduces light-induced dynamic lattice distortions via the rigid NTS backbone. These molecular interactions alleviate strain heterogeneity within the lattice and homogenize the Sn-Pb compositional gradient, thereby enhancing the structural integrity and long-term stability of Sn-Pb perovskites under operational conditions. As a result, Sn-Pb single-junction perovskite solar cells (PSCs) achieve a power conversion efficiency (PCE) of 23.2%. When integrated into a tandem configuration, the device attains an impressive PCE of 29.6% (certified PCE of 29.2%, one of the highest certified efficiencies to date), with 93.1% of the initial efficiency retained after 700 h of continuous operation. By stabilizing the lattice structure, this work lays a solid foundation for achieving both high efficiency and long-term durability in next-generation perovski...