催化学报

催化学报 ›› 2008, Vol. 29 ›› Issue (7): 607-611.

• 研究论文 • 上一篇    下一篇

碳化钨纳米晶合成及其电化学性能

曾江华,袁定胜,刘应亮,陈景星,谭三香   

  1. 暨南大学化学系纳米化学研究所, 广东广州 510632
  • 收稿日期:2008-07-25 出版日期:2008-07-25 发布日期:2012-06-07

Synthesis of Tungsten Carbide Nanocrystals and Its Electrochemical Properties

ZENG Jianghua, YUAN Dingsheng*, LIU Yingliang, CHEN Jingxing, TAN Sanxiang   

  1. Department of Chemistry, Institute of Nanochemistry, Jinan University, Guangzhou 510632, Guangdong, China
  • Received:2008-07-25 Online:2008-07-25 Published:2012-06-07

PDF

1314

被引次数

16

摘要： 用Mg作还原剂,无水乙醇和WO3分别作为C源和W源,采用简单的溶剂热法合成了碳化钨(WC)纳米晶,并讨论了温度和时间对合成WC的影响,以及其形成的机理. 通过X射线衍射、透射电子显微镜、能量色散谱和电化学方法表征了WC的物相结构、表面形貌、化学组成和电化学性能. 结果表明,合成温度低至500 ℃时也能合成六方WC相. 生成C的量超过W的量,说明纯化后的产物由C和WC组成. WC的粒径大约在40～70 nm,分布于膜状碳上. 将溶剂热法制备出的WC加入Pt/C中,其协同催化氧还原效果非常明显,起峰电势比Pt/C催化剂正移了173 mV.

关键词: 溶剂热法, 纳米晶, 碳化钨, 电催化, 氧还原

Abstract: Tungsten carbide (WC) nanocrystals were prepared by a solvothermal method using Mg as the reductant and WO3 and anhydrous ethanol as the precursors. The effect of time and temperature on the synthesis of WC was investigated and a probable formation mechanism was discussed. The obtained WC crystals were characterized byX-raydiffraction, transmission electron microscopy, energy dispersive spectroscopy, and electrochemical methods. Hexagonal WC was successfully prepared when the temperature was as low as 500 ℃. The content of carbon was more than that of W and the composition of the treated sample was C and WC only. The diameter of WC nanocrystals was ranged from 40 to 70 nm and the crystal was dispersed on C films. The WC nanocrystals promoted the Pt/C electrocatalyst ability obviously for the oxygen reduction reaction with the onset potential over 173 mV, which was more positive compared with that of the traditional Pt/C electrocatalyst.

Key words: solvothermal method, nanocrystal, tungsten carbide, electrocatalysis, oxygen reduction