前驱体碳热还原法制备纳米V(C_(1-x)N_x)粉体

Preparation of V(C_(1-x)N_x) nanopowder by carbon thermal reduction of the precursor powder

以偏钒酸铵粉末和纳米碳黑为原料，先制成含有钒源和碳源的前驱体粉末，再置入真空碳管炉中，通入氮气进行碳氮化合成V（C1-xNX）粉体，采用TG／DSC热分析、XRD、SEM和TEM等测试方法对不同合成温度下的反应产物进行了表征，结果表明：前驱体粉末可以获得混合充分均匀的反应物原料，并在1050～1100℃之间制备了相组成单一、平均粒径60nm的纳米级V（C1-xNX）粉体；当温度低于1050℃，粉体粒度小于100nm，但反应产物中有v203杂相生成；当温度高于1100℃时，随着温度的升高，粉体的粒度逐渐长大，在1200℃时颗粒之间熔融桥联。在1000～1100℃温度范围内，温度对粉体的x值影响不大，当温度高于1100℃时，z值明显减小，说明V（C1-xNX）粉体中的碳含量显著增多，氮含量明显减少。

Using NH4VO3 and nanometer carbon as raw materials, the precursor powder containing vanadium and carbon source was firstly produced then put it into a graphite vacuum furnace. Nanometer powder V（C1-xNX） was synthesized by carbonitriding at high temperature with nitrogen. The powders produced at different temperatures were characterized by TG/DSC thermal analyzer, X-ray diffraction, SEM and TEM. The results indicate that precursor powder is uniform mixed reacant and between 1 000℃ and 1 100℃ the nanometer V（C1-xNX） powder is synthesized with single phase and average particle size being 60nm. At 1 050℃ , the product contains impurity phase V203 and above 1 100℃ the particles grow bigger as the temperature increases then bridge together at 1 200℃ . Between 1 000℃ and 1 100℃ the effect of synthesis temperature on x value is indistinctive but above 1 100℃ x value decreases obviously which shows carbide content of V（C1-xNX） powder increase and nitride content decrease.