应用电位扫描法将Pd(II)离子沉积到玻碳电极表面,形成纳米结构的金属钯薄膜电极.然后在酸性溶液中控制适当的阴极电位,使该薄膜电极的钯吸收足量的活性氢,进而以吸收的氢作还原剂将Au(III)离子还原,制得Au-Pd双金属薄膜电极.扫描电镜、循环伏安法等测试表明,该电极Au-Pd沉积层对乙醇的氧化具有很高的电催化活性.
关键词：
金; 钯; 循环伏安法; 乙醇; 电催化
The nanostructured Pd thin films were directly formed on the glassy carbon electrode(GCE) substrates by using potential cycling method.The as-prepared Pd thin films deposited onto the GCE were able to absorb enough amount of hydrogen in acidic solutions at the cathodic potentials more negative than the hydrogen evolution potential.Moreover,the absorbed hydrogen could be used as the reducing agent to reduce gold(III) ions to Au nanoclusters,thereby forming bimetallic Au-Pd thin films on the GCE substrate.SEM and cyclic voltammetry characterization demonstrated that the Au-Pd thin films display much higher catalytic activity towards the electro-oxidation of ethanol than the pure Pd thin films.
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