Metal ion-containing ionic liquid assisted synthesis and enhanced photoelectrochemical performance of g-C3N4/ZnO composites

The g-C3N4/ZnO composites with various weight percent of g-C3N4 have been successfully synthesised in the presence of metal ion-containing ionic liquid bis(1-octyl-3-methylimidazolium) tetrachlorozincate ([Omim](2)ZnCl4) by a ecofriendly solvothermal method. The results of the XRD, EDS and FT-IR analyses have indicated that the as-prepared composites consist of g-C3N4 and ZnO. The results of photoelectrochemical analysis show that the interaction between the g-C3N4 and ZnO can facilitate the separation of electron-hole pairs and enhance the photocatalytic performance of g-C3N4/ZnO composites. The photocatalytic performance of g-C3N4/ZnO composites has been demonstrated by photodegradation experiments of methylene blue under visible light irradiation. The g-C3N4/ZnO composites exhibit higher photocatalytic performance than that of the pure ZnO. The optimal content of g-C3N4 in the composites is 10 wt-%. A possible mechanism of g-C3N4/ZnO composites for the photocatalytic performance has been proposed.