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A novel method to synthesize vanadium carbide (V8C7) nanopowders by thermal processing NH4VO3, C6H12O6 and urea

“…This method can prepare vanadium carbide nanopowders with good dispersion and uniform sizes at a lower temperature in comparison with conventional methods, which have been confirmed in other materials synthesis [5,23]. As we know, it was seldom reported that vanadium carbide nanopowders were synthesized by the solution-derived precursor method using NH 4 VO 3 , C 6 H 12 O 6 and urea as starting materials.…”

“…Such methods have a number of potential advantages [5,20]: (i) a high homogeneity of reactants can be achieved, (ii) the required composition for the ceramic formation can be adjusted by solution processes, and (iii) the polymer or precursor can undergo low-temperature decomposition, enabling ceramic formation under milder conditions than those used in conventional techniques. Examples for group VIb elements are the pyrolysis of chromium salicylate [21], electrochemically prepared chromium polymer precursors [22] and solution-derived molybdenum and tungsten precursors [23].…”

Synthesis of VN nanopowders by thermal nitridation of the precursor and their characterization

“…Ammonium vanadate (NH 4 VO 3 ) was used as vanadium source because it can easily dissolve in hot water [21] and it is much cheaper than vanadium oxides such as V 2 O 5 , V 2 O 3 , VO 2 , and VO. Besides, this method can prepare vanadium nitride nanopowders with good dispersion and uniform sizes at a lower temperature in comparison with conventional methods, which have been confirmed in other materials synthesis [22,23]. As we know, it was seldom reported that VN nanopowders were synthesized by the solution-derived precursor method using ammonium vanadate (NH 4 VO 3 ) and nanometer carbon black as materials of the precursor.…”

MoC x species embedded in ordered mesoporous silica framework with hierarchical structure for hydrogenation of naphthalene

“…The transformation of metastable ␣ phase carbide into stable ␤ phase carbide was observed with elevated temperature during the pyrolysis of Mo VI -melamine hybrids [14]. However, the metastable ␣ phase MoC x could be stabilized in a carbon-rich environment [26], which in the present case was created by the thermal decomposition of the P123 micelles. The DTA curve of the MoC x @OMSF preform also indicated the transformation of the carbide phase (Fig.…”