Resonance‐Hybridized Molecule Driven Perovskite Surface Sulfidation and Electron‐Transport Bridging for Efficient and Stable Inverted Perovskite Solar Cells

ABSTRACT Interfacial and bulk issues in inverted perovskite solar cells (PSCs) limit their performance and stability, and simultaneous regulation to address these issues remains challenging. Here, a simple multifunctional bulk/interface regulation strategy based on a resonance‐hybridized thiourea derivative (1‐(3‐(1H‐imidazol‐1‐yl)propyl)‐3‐(3,4‐dimethoxyphenyl)thiourea, HP3T) is proposed to simultaneously address these issues. This strategy leverages HP3T resonance rearrangement and energy levels to realize mature perovskite surface sulfidation, forming stable Pb–S passivation on the perovskite surface/grain boundaries while constructing a molecular bridge channel for photogenerated carrier transport between the perovskite and (6,6)‐phenyl‐C 61 butyric acid methyl ester (PCBM). Meanwhile, this post‐treatment improves perovskite film quality/hydrophobicity, constructs an n–n junction on it, enhances PCBM's film‐forming quality, and alleviates residual stress in the perovskite film. Benefiting from HP3T's multifunctional regulation, the carrier transport dynamics of the device improved, greatly enhancing the performance. As a result, 25.97% and 24.67% efficiencies for rigid and flexible devices were achieved, respectively, ranking these devices among the best‐performing inverted PSCs fabricated using thiourea‐derived or simple interface‐passivation strategies. Furthermore, HP3T significantly enhanced the mechanical stability of the device. After aging (3840 h in N 2 , 1200 h in air, and 565 h under maximum power‐point tracking), the device retained ∼90% of its initial efficiency.