Facile Fabrication and Enhanced Photocatalytic Performance of Ag/AgCl/rGO Heterostructure Photocatalyst

Graphene/reduced graphene oxide (rGO) modification has been demonstrated to be an efficient route to improve the photocatalytic performance of various photocatalysts by promoting the effective separation of photogenerated electrons and holes. It is highly required to develop facile and environmental-friendly methods for the preparation of graphene-based photocatalytic materials. In this study, the Ag/AgCl/rGO heterostructure photocatalyst was fabricated by a mild oxidization reaction of hydrothermally prepared Ag/rGO in FeCl3 solution. It was found that the reduction of graphene oxide (GO) was accompanied with the in situ formation of metallic Ag in a Ag[(NH3)2]+-immobilized GO solution during hydrothermal treatment, while the following in situ oxidation of metallic Ag by FeCl3 solution resulted in the formation of strongly coupled Ag/AgCl/rGO heterostructure photocatalyst. The photocatalytic experimental results indicated that all the resultant Ag/AgCl/rGO nanocomposite photocatalysts exhibited a much higher photocatalytic activity than the Ag/AgCl and physically mixed Ag/AgCl/rGO composite, and the Ag/AgCl/rGO (3.2 wt % rGO) showed the highest photocatalytic performance. The enhanced photocatalytic performance of Ag/AgCl/rGO heterostructures can be attributed to the cooperation effect of the effective separation of photogenerated carriers via strongly coupled rGO cocatalyst and the enrichment of organic molecules on the rGO nanosheets. Considering the facile preparation and its high photocatalytic activity, it is possible for the present Ag/AgCl/rGO nanocomposites to be widely applied in various fields such as air purification and wastewater treatment.