Facile route to prepare TaC, NbC and WC nanoparticles

Abstract

By a novel solid-state reaction process using amorphous C₃N₄ (a-C₃N₄) and transition metal oxides as starting reagents, cubic TaC, NbC and hexagonal WC nanoparticles were successfully synthesized at 1150 °C. The products were characterized by power X-ray diffraction (XRD), field-emission scanning electron microscope (FE-SEM), energy-dispersive X-ray spectroscopy (EDX), transmission electron microscopy (TEM) and high-resolution TEM (HRTEM). The experimental results show that a-C₃N₄ obtained by the reaction between C₃N₃Cl₃ and Li₃N is a highly efficient carburation reagent and the transition metal oxides are completely transformed into the corresponding metal carbide nanoparticles at 1150 °, respectively, which is significantly lower than that reported for the traditional preparation of carbides, typically >1600 °. The TaC, NbC and WC nanoparticles are found to have an average particle size of 10 nm, 15 nm and 8 nm by TEM observation, respectively.

Keywords

a-C₃N₄ / TaC / NbC / WC / nanoparticles

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