Laser-Induced Surface Hydroxylation of Nickel Oxide Boosting Monolayer Assembly for High-Performance Perovskite Solar Modules

Abstract

Self-assembled monolayers (SAMs) are crucial for high-efficiency inverted perovskite solar cells (PSCs) and modules (PSMs), yet their stability and uniformity on magnetron-sputtered NiOx substrates are fundamentally limited by sparse hydroxylation and unstable mono-/bidentate anchoring, leading to interfacial degradation during large-area processing. Conventional hydroxylation strategies suffer from unstable physisorbed groups or environmental concerns, impeding scalable PSM manufacturing. Here, we introduced a green, precise, and scalable laser-induced hydroxylation strategy to overcome these challenges. The high-energy laser irradiation precisely removes surface lattice oxygen from NiOx films by photothermal effect, and induces the generation of abundant oxygen vacancies. Subsequent air annealing activates these vacancies for catalytic water dissociation, constructing hydroxyl-rich NiOx surface with supplementary undercoordinated nickel sites. This surface enables SAM anchoring via direct coordination bonds, upgrading to a robust tridentate configuration. Consequently, dense and stable SAM coverage strengthens interfacial electronic coupling, suppresses non-radiative recombination, and promotes ordered perovskite crystallization. The resulted large-area PSM (65 cm2) attained 22.70% efficiency (certified as 22.01%), which represents one of the highest efficiencies ever reported for large-area PSMs (50-200 cm2). The unencapsulated PSM can maintain >91% initial PCE after 1500 hours aging under 85 oC in N2 (ISOS-D-2). This strategy provides a scalable pathway toward stable, high-performance perovskite photovoltaics.