Tungsten carbide (WC) nanopowders synthesized via novel core-shell structured precursors

WC powders with a size in the range of 20-60 nm were prepared through carbothermal reduction of a novel core-shell structured precursor in vacuum. The samples were characterized by X-ray diffraction (XRD), transmission electron microscope (TEM), high-resolution transmission electron microscopy (HRTEM) and X-ray photoelectron spectroscopy (XPS). The thermolysis process of the precursor has been investigated by themogravimetric analysis and differential thermal analysis (TG-DSC). The results revealed that the single phase WC nanopowders were synthesized at 980 °C for 1 h. Spectra of XPS indicate that the surface of the specimen mainly consists of W, C and O three species elements only. The effects of experimental parameters and reaction mechanism have been explored. Mainly due to the homogeneous chemical composition of the precursor, the synthesizing temperature was greatly lower than the conventional method.