Sulfonic Surfactant Promises Uniform Wide‐Bandgap Perovskite Solar Modules for All‐Perovskite Tandem Photovoltaics

3-(N, N-Dimethyloctylammonio) propananesulfonate inner salt (DOPS) as an ionic surfactant additive is utilized in large-area wide-bandgap (WBG) perovskite film preparation. The well-designed interaction between DOPS and WBG compositions effectively regulates the crystallization process and passivates the uncoordinated Pb²⁺. These improvements enable champion efficiencies of 16.38% and 23.41% for WBG and all-perovskite tandem solar modules.

Abstract

The development of scalable all-perovskite tandem solar cells offers a promising pathway for perovskite photovoltaic commercialization. However, the certified efficiency of all-perovskite tandem mini-modules still lags much behind their small-area (≈0.1 cm²) counterparts. This performance gap primarily stems from inhomogeneities and inferior crystallinity in wide-bandgap (WBG) perovskite solar cells (PSCs) when scaling up. In this work, we introduced 3-(N, N-Dimethyloctylammonio) propananesulfonate inner salt (DOPS) as an ionic surfactant additive to suppress pinhole formation and enhance the uniformity of large-area perovskite films. The well-designed interaction between DOPS and WBG compositions effectively regulates the crystallization process and passivates the uncoordinated Pb²⁺, resulting in a uniform and high-quality WBG perovskite film with suppressed non-radiative recombination. These improvements enable champion efficiencies of 19.57% and 16.38% for WBG PSCs with aperture areas of 1.0 and 20.07 cm², respectively. Furthermore, when integrating this optimized WBG device into all-perovskite tandem solar cells, it yields impressive PCEs of 27.82% (1.0 cm²) and 23.41% (20.07 cm²). Overall, these findings present an effective strategy for enhancing large-area uniformity via the surfactant synergistic effect of crystallization regulation and defect passivation.