Fabrication of an Ag/Ag2MoO4 plasmonic photocatalyst with enhanced photocatalytic performance for the degradation of ciprofloxacin

Abstract

A silver/silver molybdate (Ag/Ag₂MoO₄) composite was successfully synthesized through in situ reduction of Ag₂MoO₄ using NaBH₄ at room temperature and characterized by various analytical techniques. The photocatalytic activity of the composite was evaluated by the degradation of the colorless antibiotic agent ciprofloxacin (CIP) under visible light irradiation. The experimental results indicated that the as-fabricated Ag/Ag₂MoO₄ composite showed greatly enhanced photocatalytic performance compared with pure Ag₂MoO₄, and exhibited high photodegradation efficiency with 99.5% removal of CIP in 60 min and excellent stability in five consecutive cycles. The improved photocatalytic performance could be mainly attributed to the surface plasmon resonance (SPR) effect of the Ag nanoparticles in the region of visible light. The active species trapping experiments and ESR analysis suggested that ˙OH and h⁺ were the main active species for the photocatalytic degradation. Eventually, a possible photocatalytic mechanism was proposed.