Silver Nanoparticle-Loaded Conjugated Microporous Polymers: A Highly Efficient Photocatalyst for Methylene Blue Degradation.

Abstract

Photocatalytic degradation offers a promising solution for dye wastewater treatment using solar energy, addressing regeneration and secondary pollution issues, and mitigating regeneration and secondary pollution concerns associated with conventional methods. However, polymer-based photocatalysts encounter several challenges, including complex synthesis routes, limited photocatalytic efficiency, and prolonged reaction durations. Herein, we synthesized four functionalized conjugated microporous polymers (CMPs) containing naphthyl, anthryl, phenyl, and n-propyl groups via Sonogashira-Hagihara coupling, and developed a silver nanoparticle-decorated conjugated microporous polymers composite that achieved near-complete (99.99%) degradation of methylene blue within 20 min under visible light, retaining 99.87% efficiency after five cycles. Mechanistic studies revealed the generation of reactive oxygen species (hydroxyl radical (·OH) and superoxide anion (·O₂ ^-)) responsible for efficient dye mineralization to degradation products, including CO₂ and H₂O. This work provides a new strategy for designing high-performance photocatalytic composites for wastewater treatment.