关键词: 碳化钨催化剂, 纳米晶薄膜, 电催化, 甲醇电氧化

Abstract: Nano-crystalline tungsten carbide thin films were fabricated on graphite substrates by plasma enhanced chemical vapour deposition in H₂ and Ar atmosphere, using WF₆ and CH₄ as precursors.The crystal phase, structure and chemical components of the films were characterized with X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy-dispersive spectrometer (EDS),respectively.The results showed that the film prepared at CH₄/WF₆ concentration ratio of 20,working pressure of 100Pa and temperature of 800℃ were composed of sphere particles with a diameter of 20—35 nm Electrochemical investigations show that the electrochemical surface area of electrode of the film was large.The electrode of the film exhibited higher electro-catalytic activity in the reaction of methanol oxidation,and its catalytic properties were similar to those of Pt or Pt group catalysts.The constant current of the film catalyst was 123.6 mA·cm^-2 in the mixture solution of H₂SO₄ and CH₃OH at the concentration of 0.5 mol·L^-1 and 2.0 mol·L^-1 respectively at 70 ℃, and its constant potential was only 0.306 V(vs.SCE).

Key words: 碳化钨催化剂, 纳米晶薄膜, 电催化, 甲醇电氧化