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

Abstract

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.