Green Porphyrin Interface Anchoring Enables >24% Efficiency in n‐i‐p Perovskite Solar Minimodules

Abstract

Abstract Scaling of n‐i‐p perovskite photovoltaics to large‐area modules is impeded by intensified nonradiative recombination at the buried interface of perovskite and electron transport layer, resulting in severe carrier transport losses. Therefore, effective and environmentally benign interfacial modifiers are urgently required. Herein, a solution‐processable tetrasulfonated porphyrin interlayer with a strong dipole moment and multiple coordination sites is designed, which can be vertically anchored at the SnO 2 /perovskite interface via a simple water‐based post‐treatment. Two sulfonic acid groups form robust bonds with Sn atoms in SnO 2 , while the remaining two coordinate with Pb in the perovskite lattice, passivating interfacial defects. Strong electron‐withdrawing character of sulfonic acid groups imparts the porphyrin with a pronounced intrinsic dipole moment (10.12 D), which significantly promotes rapid and efficient electron extraction and transport from perovskite to SnO 2 . Consequently, the treated perovskite modules deliver a power conversion efficiency of 24.49% (certified 23.95%), ranking among the highest reported, while small‐area devices reach 26.66%. Notably, after more than 1500 h of maximum power point tracking, the treated device preserves 90% of its initial efficiency. This study demonstrates an environmentally benign interfacial engineering strategy based on dual‐sided chemical coordination, providing a promising pathway toward scalable fabrication of high‐efficiency perovskite optoelectronic devices.