Morphology-controlled synthesis of CdSe microspheres on graphene oxide sheets and their photocatalytic properties

Abstract

Different morphologies of CdSe microspheres have been synthesized on reduced graphene oxide (rGO) sheets by a simple hydrothermal process using Cadmium nitrate and Se powder as the raw materials. The hybrid CdSe/rGO samples were intensively investigated by XRD, EDS, XPS, SEM and UV–vis absorption spectrum. It was found that the EDTA/Cd2+ molar ratio is crucial for the formation of morphology of CdSe grown on rGO sheets. The results of XRD reveal that the as-prepared CdSe microspheres have zinc blend structure. The results of Raman spectra, EDS, XPS and SEM show that the CdSe microspheres are grown on rGO sheets. In addition, UV–vis absorption spectrum indicates that the CdSe/rGO nanocomposites are believed to serve as photosensitizers to extend the absorption spectrum to visible light region. Superior photocatalytic activity of urchin-like CdSe microspheres grown on rGO sheets relative to those of other CdSe/rGO nanocomposites was observed under visible light irradiation. The growth mechanism for the formation of CdSe microspheres grown on rGO sheets was also described.