›› 2011, Vol. 19 ›› Issue (1): 145-150.

• PRODUCT ENGINEERING AND CHEMICAL TECHNOLOGY • Previous Articles     Next Articles

Preparation of WC@TiO2 Core-shell Nanocomposite and Its Electrocatalytic Characteristics

LI Guohua, CHEN Dan, YAO Guoxing, SHI Binbin, MA Chun’an   

  1. 1. State Key Laboratory Breeding Base of Green Chemistry-Synthesis Technology, Zhejiang University of Technology, Hangzhou 310032, China;
    2. Research Center of Nano Science&Technology, School of Chemical Engineering&Materials Science, Zhejiang University of Technology, Hangzhou 310032, China
  • Received:2010-06-29 Revised:2010-11-06 Online:2011-02-28 Published:2011-02-28
  • Supported by:
    Supported by the National Natural Science Foundation of China(20476097);the Zhejiang Natural Science Foundation(Y4080209,Y406094);the Science Plan of Zhejiang Province(2007F70039);the Scientific Starting Fund of Zhejiang University of Technology

Preparation of WC@TiO2 Core-shell Nanocomposite and Its Electrocatalytic Characteristics

李国华, 陈丹, 姚国新, 施斌斌, 马淳安   

  1. 1. State Key Laboratory Breeding Base of Green Chemistry-Synthesis Technology, Zhejiang University of Technology, Hangzhou 310032, China;
    2. Research Center of Nano Science&Technology, School of Chemical Engineering&Materials Science, Zhejiang University of Technology, Hangzhou 310032, China
  • 通讯作者: LI Guohua, E-mail: nanozjut@zjut.edu.cn
  • 基金资助:
    Supported by the National Natural Science Foundation of China(20476097);the Zhejiang Natural Science Foundation(Y4080209,Y406094);the Science Plan of Zhejiang Province(2007F70039);the Scientific Starting Fund of Zhejiang University of Technology

Abstract: Monotungsten carbide and titania nanocomposite with core-shell(WC@TiO2)structure was prepared by a new approach of spray drying and reduction-carbonization reaction,with titania nanopowder and ammonium metatungstate as precursors,methane as carbon source,and hydrogen as reduction gas.The sample was characterized by X-ray diffraction,scanning electron microscope,high resolution transmission electron microscope and X-ray energy dispersion spectroscopy.The results show that its crystal phase is composed of brookite,tungsten and monotungsten carbide.The morphology of the sample particle is irregular sphere-like,with a diameter smaller than 100 nm.Its chemical components are titanium,tungsten,carbon and oxygen.Monotungsten carbide nanoparticles lie on the surface of titania core and form an incomplete shell around titania core in the nanocomposite.The measurement with a microelectrode system of three electrodes shows that the sample is electrocatalytic active to nitrophenol in basic solution at room temperature.Its peak potential is at 0.988 V(vs saturated calomel electrode (SCE)),which is more negative than the peak potential,0.817 V(vs SCE),of mesoporous monotungsten carbide, and its peak current is 8.809μA,which is higher than the peak current,4.058μA,of mesoporous monotungsten carbide.The hydrogen generation potential of the sample is at1.199 V(vs SCE),which is more negative than that of pure nanosized monotungsten carbide at 1.100 V(vs SCE).These results show that the presence of titania in the sample can lower the peak potential of nitrophenol electrocatalysis and its hydrogen generation potential,and increase its peak current of nitrophenol electrocatalysis in basic solution at room temperature.This indicates a synergistic effect of titania and monotungsten carbide in electrocatalysis.

Key words: tungsten carbide, titania, nanocomposite, core-shell, electrocatalytic performance

摘要: Monotungsten carbide and titania nanocomposite with core-shell(WC@TiO2)structure was prepared by a new approach of spray drying and reduction-carbonization reaction,with titania nanopowder and ammonium metatungstate as precursors,methane as carbon source,and hydrogen as reduction gas.The sample was characterized by X-ray diffraction,scanning electron microscope,high resolution transmission electron microscope and X-ray energy dispersion spectroscopy.The results show that its crystal phase is composed of brookite,tungsten and monotungsten carbide.The morphology of the sample particle is irregular sphere-like,with a diameter smaller than 100 nm.Its chemical components are titanium,tungsten,carbon and oxygen.Monotungsten carbide nanoparticles lie on the surface of titania core and form an incomplete shell around titania core in the nanocomposite.The measurement with a microelectrode system of three electrodes shows that the sample is electrocatalytic active to nitrophenol in basic solution at room temperature.Its peak potential is at 0.988 V(vs saturated calomel electrode (SCE)),which is more negative than the peak potential,0.817 V(vs SCE),of mesoporous monotungsten carbide, and its peak current is 8.809μA,which is higher than the peak current,4.058μA,of mesoporous monotungsten carbide.The hydrogen generation potential of the sample is at1.199 V(vs SCE),which is more negative than that of pure nanosized monotungsten carbide at 1.100 V(vs SCE).These results show that the presence of titania in the sample can lower the peak potential of nitrophenol electrocatalysis and its hydrogen generation potential,and increase its peak current of nitrophenol electrocatalysis in basic solution at room temperature.This indicates a synergistic effect of titania and monotungsten carbide in electrocatalysis.

关键词: tungsten carbide, titania, nanocomposite, core-shell, electrocatalytic performance