Design and synthesis of surface-controlled CuOx/rGO nanocomposites with unusually high efficiency in catalytic conversion of organic reactants in the presence of NaBH4

Surface-controlled CuOx/rGO nanocomposite has been successfully fabricated in this study using a simple hydrothermal method. In addition to the characterization by X-ray diffraction (XRD), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS) and N2 adsorption/desorption, the catalytic conversions of 4-nitrophenol (4-NP), methylene blue (MB) or rhodamine B by the CuOx/rGO nanocomposite in the presence of NaBH4 were carried out. The results demonstrate that all the selected probe reactants show no adsorption on the as-prepared CuOx/rGO nanocomposite, however, their conversions are close to 100% and can be carried out within several minutes. The excellent catalytic activities may be associated with the multi-valenced copper species and the controlled surface of the CuOx/rGO nanocomposite. In the meantime, the CuOx/rGO nanocomposite has a better stability and can be reused for many times without obvious decrease in activity, suggesting a great potential of the as-prepared CuOx/rGO nanocomposite for catalytic degradation of organic pollutants.