Fabrication and characterization of Ag/BiOI/GO composites with enhanced photocatalytic activity

A ternary silver/bismuth oxyiodide/graphene oxide (Ag/BiOI/GO) composite photocatalyst was prepared with a facile chemical method; the BiOI modification was performed through noble metal surface sedimentation and nonmetal doping. The morphologies, chemical properties, and photocatalytic performances of the photocatalysts were characterized in detail using SEM, TEM, XRD, XPS, FT-IR, Raman spectroscopy, UV-Vis spectroscopy, EIS and PL. Compared with BiOI, Ag/BiOI, and GO/BiOI, the prepared Ag/BiOI/GO catalyst (doped with 2.0 wt% GO and 1.5 wt% Ag) exhibited the highest photocatalytic activity, with a RhB degradation rate of up to 99.12% within 120 min. The Ag/BiOI/GO catalyst was stable even after being recycled and reused. The photocatalytic mechanism could be that the coexistence of Ag and GO on the BiOI greatly promotes the visible light harvesting ability while inhibiting the recombination of photogenerated electron/hole pairs. This work provides novel insights into the development of new photocatalytic materials for organic compound removal.