Self-assembled encapsulation of graphene oxide/Ag@AgCl as a Z-scheme photocatalytic system for pollutant removal

In this study, we have demonstrated a Z-scheme photocatalytic system using Ag@AgCl encapsulated with graphene oxide (GO) (AEGO) composites, where GO and AgCl act as a highly activated photocatalyst, and metallic Ag shuttles photogenerated electrons from the excited GO and AgCl under visible light irradiation. The electron-hole pairs of the low energy level could be recombined in space by metallic Ag as a solid-state electron mediator, the remaining electron-hole pairs of the high energy level are for two photochemical reactions that operate in parallel. The Z-scheme photocatalytic system from the AEGO composite displays a much higher photocatalytic activity than Ag@AgCl-reduced graphene oxide (RGO) with the same quantitative graphene loading (15 wt%) for the degradation of methylene blue (MB). This work may provide a guide to the design of photocatalysts by the use of GO directly.