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TiO2/WC core-shell nanocomposite was prepared by a new approach of spray drying and reduction-carbonization reaction,using titania nanopowder and ammonium metatungstate as precursors,methane as carbon source and hydrogen as reduction gas.The samples were characterized by X-ray diffraction,scanning electron microscopy,high resolution transmission electron microscopy and X-ray energy dispersion spectroscopy.The results show that the morphology of the particle of the sample is irregular sphere-like,with a diameter smaller than 100 nm; the sample is composed of brookite,tungsten and monotungsten carbide; the chemical components of the sample are titanium,tungsten,carbon and oxygen; titania and monotungsten carbide form a core-shell structure,with monotungsten carbide nanoparticles lie on the surface of titania core and form an incomplete shell around titania core,as shown in fig.1.The electrocatalytic activity of the sample for n-nitrophonel was measured by powder microelectrode of three electrodes system in basic solution.The results show that the sample is electrocatalytic active to n-nitrophonel in basic solution at room temperature; its peak voltage is at -0.988 V,which is more negative than the peak voltage,-0.817 V,of mesoporous monotungsten carbide; its peak current is 8.809 μA,which is higher than the peak current,4.058 μA,of mesoporous monotungsten carbide.The hydrogen generation voltage of the sample is at -1.199 V,which is more negative than that of pure nanosized monotungsten carbide at -1.100 V,as shown in fig.2.These results show that the presence of titania in the sample can lower the peak voltage of nitrophenol electrocatalysis and its hydrogen generation voltage,and increase its peak current of nitrophenol electrocatalysis.This indicates a synergistic effect exists between titania and monotungsten carbide in electrocatalysis.