Synthesis of vanadium carbonitride nanopowders from solution derived precursor via carbothermal reduction

Abstract

A study on the carbothermal synthesis of nanopowders vanadium carbonitride was conducted by using a solution derived precusor mixture of ammonium vanadate (NH₄VO₃) and nanometre sized carbon black in a vacuum carbon tube furnace with gaseous nitrogen. The effect of isothermal treatment time ranging from 0˙5 to 2 h at a sintering temperature 1373 K was studied. The particles obtained in this work were characterised by X-ray diffraction, scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The results show that VC_1-xN_x particles prepared at 1373 K for 1 h isothermal time are composed of a single phase and distributed homogeneously, exhibiting a spherical shape with an average particle size of ∼90 nm. The x value as a function of [N]/([C]+[N]) of different samples is given by Vegard's law, depending on the precise lattice parameter. The possible mechanism for the process is also discussed.