Suppressing solvent adducts via coordination competition enables scalable perovskite photovoltaics

Scalable coating methods are indispensable for the commercialization of perovskite photovoltaics. However, fundamental divergences in crystallization dynamics hinder the direct adaptation of spin-coating optimization strategies. Furthermore, the limited understanding of crystallization control under scalable conditions constrains the fabrication of high-quality perovskite films. Herein, we identify the solvent-precursor interaction time (τint) as the critical, yet previously overlooked, kinetic parameter governing film quality in scalable processes. We demonstrate the prolonged τint inherent to blade coating stabilizes solvent-adduct phases, increases solvent retention, and ultimately degrades film crystallinity. To resolve this, we introduce a dynamic coordination competition strategy that modulates the precursor coordination equilibrium, thereby effectively shortening τint and yielding high-crystallinity films with enhanced phase purity. Consequently, the blade-coated devices deliver power conversion efficiencies (PCEs) of 26.5% (0.0665 cm2) and 22.9% (728.0 cm2). Our findings provide a kinetic knob for crystallization control and establish a robust protocol for large-area manufacturing of high-quality perovskite films. Scalable fabrication of perovskite films for large-area solar cells remains a critical challenge. Jin et al. identify the solvent-precursor interaction time as a crucial, yet overlooked, kinetic parameter controlling crystallization and propose a protocol for manufacturing high-quality perovskite films.