In situ preparation of a nanocomposite comprising graphene and α-Fe2O3 nanospindles for the photo-degradation of antibiotics under visible light

Abstract

Few layer thick graphene sheets are exfoliated in an aqueous medium by using iron containing imidazolium based ionic liquid (IL; [C₁₆mim][FeCl₄]) in high yield exhibiting excellent dispersion stability. Subsequently, IL that stabilizes the graphene sheets is exploited for the in situ preparation of α-Fe₂O₃ nanospindle (NS) decorated graphene sheets, for the first time. The prepared α-Fe₂O₃@graphene nanocomposite (NC) shows enhanced photocatalytic activity for the degradation of an antibiotic, sulfamethoxazole, under visible light. The enhanced photocatalytic activity of the NCs as compared to bare α-Fe₂O₃ NSs is probed using computational simulations, where graphene is observed to sensitize α-Fe₂O₃ NSs in the photoexcitation process. This increases the electron charge density in the conduction band of α-Fe₂O₃ NSs, resulting in enhanced photocatalytic efficiency.