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

Abstract

Graphene/reduced\ngraphene oxide (rGO) modification has been demonstrated to be an efficient\nroute to improve the photocatalytic performance of various photocatalysts\nby promoting the effective separation of photogenerated electrons\nand holes. It is highly required to develop facile and environmental-friendly\nmethods for the preparation of graphene-based photocatalytic materials.\nIn this study, the Ag/AgCl/rGO heterostructure photocatalyst was fabricated\nby a mild oxidization reaction of hydrothermally prepared Ag/rGO in\nFeCl₃ solution. It was found that the reduction of graphene\noxide (GO) was accompanied with the in situ formation of metallic\nAg in a Ag­[(NH₃)₂]⁺-immobilized GO\nsolution during hydrothermal treatment, while the following in situ\noxidation of metallic Ag by FeCl₃ solution resulted in\nthe formation of strongly coupled Ag/AgCl/rGO heterostructure photocatalyst.\nThe photocatalytic experimental results indicated that all the resultant\nAg/AgCl/rGO nanocomposite photocatalysts exhibited a much higher photocatalytic\nactivity than the Ag/AgCl and physically mixed Ag/AgCl/rGO composite,\nand the Ag/AgCl/rGO (3.2 wt % rGO) showed the highest photocatalytic\nperformance. The enhanced photocatalytic performance of Ag/AgCl/rGO\nheterostructures can be attributed to the cooperation effect of the\neffective separation of photogenerated carriers via strongly coupled\nrGO cocatalyst and the enrichment of organic molecules on the rGO\nnanosheets. Considering the facile preparation and its high photocatalytic\nactivity, it is possible for the present Ag/AgCl/rGO nanocomposites\nto be widely applied in various fields such as air purification and\nwastewater treatment.