Ni-B非晶态合金电极上乙醇的电氧化及其动力学参数的测定

应用循环伏安法研究了碱性介质中Ni-B非晶态合金纳米粉末微电极和化学镀Ni-B非晶态合金微盘电极上乙醇的电催化氧化. 结果表明, Ni-B非晶态合金纳米粉末微电极和化学镀Ni-B非晶态合金微盘电极对碱性溶液中乙醇的氧化均具有很高的电催化作用, 且前者的电催化氧化活性高于后者. 运用稳态极化曲线测定了Ni-B非晶态合金纳米粉末微电极上乙醇的电催化氧化动力学参数. 与高择优取向(220)镍电极比较, 碱性介质中Ni-B非晶态合金纳米粉末微电极上乙醇的电催化氧化速率显著提高. 采用循环伏安法测定的Ni-B非晶态合金纳米粉末微电极上Ni(OH)2的质子扩散系数高出文献报道的镍纳米线电极和表面化学镀Co的球形Ni(OH)2粉末电极约2个数量级.

Electrooxidation of Ethanol at Ni-B Amorphous Alloy Electrode and Measurements of Kinetic Parameters

Electrocatalytic oxidation of ethanol at the nano Ni-B amorphous alloy powder microelectrode and the electroless Ni-B amorphous alloy microdisk electrode in alkaline media was studied by using cyclic voltammetry. It was found that the nano Ni-B amorphous alloy microelectrode had higher electrocatalytic activity for the oxidation of ethanol than the electroless Ni-B amorphous alloy microdisk electrode. The kinetic parameters were determined with the steady polarization curves. The rates of electrocatalytic oxidation of ethanol at the nano Ni-B amorphous alloy microelectrode in alkaline media were much higher than those at the highly preferred orientation (220) nickel electrode. The proton diffusion coefficient of Ni(OH)2 at the nano Ni-B amorphous alloy powder microelectrode determined by cyclic voltammetry was increased by about 2 orders of magnitude, in comparison with the reported values at Ni nanowire electrode and the spherical Ni(OH)2 microencapsulated by cobalt.