Reduced graphene oxide coupled CdS/CoFe2O4 ternary nanohybrid with enhanced photocatalytic activity and stability: a potential role of reduced graphene oxide as a visible light responsive photosensitizer

Abstract

We report the coupling of a CdS/CoFe₂O₄ (CdS/CFO) core/shell nanorod heterostructure onto the 2D platform of reduced graphene oxide (RGO) sheets by a facile soft chemical route. Intimate interfacial contact between CdS, CFO and RGO is achieved in the synthesis. The CdS/CFO/RGO nanohybrid exhibits an enhanced photocatalytic activity for the degradation of methylene blue under visible light irradiation. In addition to enhanced photocatalytic activity, this trio-coupled nanocomposite exhibits enhanced photostability and is magnetically separable from an aqueous solution due to the presence of CFO in the composite nanostructure and thus can be used for repeated operations of the photocatalytic process. A mechanism for the enhanced photocatalytic activity of the CdS/CFO/RGO has been proposed where the RGO in the ternary nanocomposite serves as a visible light responsive photosensitizer. Our present work indicates that the careful choice of a semiconductor core–shell nanostructure and its coupling with reduced graphene oxide has great potential in the design of efficient and stable visible light responsive photocatalytic materials.