Acta Phys. -Chim. Sin. ›› 2014, Vol. 30 ›› Issue (5): 891-898.doi: 10.3866/PKU.WHXB201402241

• ELECTROCHEMISTRY AND NEW ENERGY • Previous Articles     Next Articles

Preparation and Electrocatalytic Activity of Tungsten Carbide and Tungsten-Iron Carbide Composite with Core-Shell Structure

CHEN Hui1, CHEN Dan1, XIE Wei-Miao1, ZHENG Xiang1, LI Guo-Hua1,2,3   

  1. 1 School of Chemical Engineering, Zhejiang University of Technology, Hangzhou 310032, P. R. China;
    2 State Key Breeding Base of Green Chemistry Synthesis Technology, Hangzhou 310032, P. R. China;
    3 Research Center of Nanoscience and Engineering Technology, Zhejiang University of Technology, Hangzhou 310032, P. R. China
  • Received:2013-11-07 Revised:2014-02-24 Published:2014-04-25
  • Contact: LI Guo-Hua E-mail:nanozjut@zjut.edu.cn
  • Supported by:

    The project was supported by the National Natural Science Foundation of China (21173193, 21301154) and Science and Technology Project of Zhejiang Province, China (2013C37104, 2009R50002-15).

Abstract:

A tungsten carbide and tungsten-iron carbide composite with a core-shell structure was prepared through a combination of surface coating and in situ reduction-carbonization, using ammonium metatungstate as the tungsten source and iron hydroxide as the iron source. The main crystal phases of the composite were tungsten-iron carbide (Fe3W3C), monotungsten carbide (WC), and bitungsten carbide (W2C). In the core-shell composite, Fe3W3C formed the core, and the shell consisted of WC and W2C. The electrocatalytic activity for methanol oxidation of the composite was measured by cyclic voltammetry with a three-electrode system in acidic, neutral, and alkaline aqueous solutions. The results show that the electrocatalytic activity of the composite is higher than those of tungsten carbide particles and mesoporous hollow microspheres. The activity is affected by the properties of the solution in which the reaction is performed, and is related to the crystal phase and microstructure of the composite. These results indicate that the electrocatalytic activity of tungsten carbide can be adjusted by changing the properties of the reaction solution and controlled by adjusting the crystal phase and microstructure of the composite. Furthermore, the activity can be improved through formation of a core-shell structure; this is an efficient way to improve the electrocatalytic activity of tungsten carbide.

Key words: Tungsten carbide, Tungsten-iron carbide, Core-shell structure, Electrocatalytic activity, Adjusting