In situ synthesis method was used to prepare V8C7–Cr3C2nanocomposite.Ammonium vanadate, ammonium dichromate and nanometer carbon black were used as raw materials.The products were characterized by X-ray diffractometry(XRD), scanning electron microscopy(SEM), transmission electron microscopy(TEM), thermogravimetric and differential scanning calorimetry(TGDSC) and X-ray photoelectron spectroscopy(XPS) techniques.The results show that V8C7–Cr3C2nanocomposite with an average crystallite size of 25.4 nm can be synthesized at 1200 °C for 1 h.The synthesis temperature required by the method is at least 200 °C lower than that required by the conventional approaches for preparing vanadium and chromium carbides.The powders show good dispersion and are mainly composed of spherical or nearly spherical particles with a mean diameter of about 30 nm.The weight loss ratio of the precursor throughout the reaction process reaches 58 wt%.Three exothermic peaks and four endothermic peaks occur during the reaction.The surface of the specimen is mainly composed of V, Cr, C and O elements.
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