碳含量对纳米碳化钒制备的影响

Effect of Carbon Content on Synthesis of Nano-sized Vanadium Carbide

以偏钒酸铵和纳米炭黑为原料,采用水溶液前驱体方法制备纳米碳化钒(V8C7)粉末。采用X射线衍射仪(XRD)、扫描电镜(SEM)和热重—差热分析仪(TG-DTA)对反应产物进行表征和分析。结果表明:在24%～28%配碳量范围内,随着碳含量增加,晶粒尺寸逐渐减小,当配碳量为28%时,相组成为单一的V8C7,晶粒尺寸达到最小值32.6nm;碳含量为28%时,粉末显示出较好的分散性,主要由直径100nm左右的球形颗粒组成。

The nano -sized vanadium carbide （V8C7 ） is prepared by solution -derived precursor method with ammonium vanadate （ NH4VO3 ） and nanometer carbon black as raw material. The product are characterized and analyzed by XRD, SEM and TG - DTA. The result shows that the crystallite sizes decrease with the increasing of carbon content,which is in the range of 24% -28%. The single phase V8C7 and the smallest erystallite size of 32.6 nm can be obtained when the carbon content is 28% , the powders show good dispersion, it is mainly composed of spherical particles with a mean diameter of 100 nm.