Fabrication of ternary Mn doped ZnO nanoparticles grafted on reduced graphene oxide (RGO) sheet as an efficient solar light driven photocatalyst

Abstract

A simple hydrothermal method is adopted to prepare ternary Mn doped ZnO nanoparticles uniformly grafted on reduced graphene oxide (RGO) sheets. The effect of Mn doping on ZnO/RGO nanocomposite has been investigated using different characterization techniques. Field emission scanning electron microscope (FESEM) images clearly show the uniform distribution of nanoparticles on RGO sheets. The doping of Mn in ZnO/RGO composites have been confirmed by X-ray photoelectron spectroscopy (XPS). Photocatalytic activities of as-prepared samples were examined by the degradation of Rhodamine B (RhB) and Congo red (CR) under sun light. The prepared ternary heterojunction photocatalyst exhibit the excellent photocatalytic activity for degradation of RhB (degradation rate nearly 99% within 140 min) and CR (degradation rate nearly 100% within 160 min) under sunlight irradiation which is higher than that of binary ZnO/RGO heterojunction. The improved photocatalytic performance of the ternary nanocomposite can be ascribed to extend solar light absorption, enhanced adsorption of the composite catalyst surface and efficient charge separation of photo-induced electrons.