Synthesis of WC nanopowders from novel precursors

Nano-WC powders with granular particle of ~ 20–80 nm were synthesized by a new precursor method, namely carbothermal reduction–carburization of amorphous WO3-C mixture, which was made initially from salt solution containing tungsten and carbon elements by air drying and subsequent calcining at 400 °C for 1 h. The reaction products were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS) techniques. The results show that the synthesizing temperature of WC powders was reduced greatly by the novel precursor method. Thus, the preparation of the single-phase nano-WC powders is at only 1000 °C for 2 h. The lowering of synthesizing temperature is mainly due to the homogeneous chemical composition of the amorphous oxide-carbon mixture.

Research highlights
► Nano-WC powders were successfully synthesized at only 1000 °C for 2 h.
► Simultaneous use of W and C precursors causes amorphous structure of WO3-C mixture.
► The amorphous WO3-C mixture promotes the lowering of synthesizing temperature.