The formation of visible light-driven Ag/Ag₂O photocatalyst with excellent property of photocatalytic activity and photocorrosion inhibition

Ag/Ag₂O composites were prepared via an extremely simple solvent-free chemical technique. The obtained Ag/Ag₂O samples exhibited superior visible-light degradation efficiency for methyl orange removal. The degradation rate constant of as-obtained composite is almost 2 times as that of commercial Ag₂O, and has only little change after five cycles of utilization. The excellent photocatalytic properties of Ag/Ag₂O materials could be ascribed to desirable absorption property and surface plasmon resonance of metal silver on the surface of semiconductor Ag₂O. Meanwhile, the unstable and photo-sensitive disadvantages of commercial Ag₂O due to the photocorrosion could be largely suppressed in the presence of metallic Ag for Ag/Ag₂O composites, which plays an important role as an electron sink to receive the photo-generated electrons from Ag₂O, accordingly restraining the reduction of Ag⁺ in Ag₂O and improving the recyclability of Ag₂O. With the assistance of scavengers and ESR technique, the h⁺ and O₂^- were proved to be crucial reactive species in the pathways of photocatalytic degradation reaction.