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上甲醇的电催化氧化.结果表明,Ni-B非晶态合金纳米粉末微电极表现出很高的甲醇氧化电催化活性,较之高择优取向(220)的镍电极,其氧化起始电位负移了0.04V;氧化电流密度约大2个数量级,根据稳态极化曲线测定,与高择优取向(220)镍电极相比较,在Ni-B非晶态合金纳米粉末微电极上,Ni(Ⅲ)与甲醇反应和Ni(Ⅱ)氧化为Ni(Ⅲ)及其逆反应的速率常数依次约大2个、3个和3个数量级.
Electrocatalytic oxidation of methanol at the nano Ni-B amorphous alloy powder-microelectrode in alkaline media was studied by using cyclic voltammetry.Compared to the highly preferred orientation(220) nickel electrode,The onset potential of methanol electrooxidation at the nano Ni-B microelectrode is negatively shifted about 0.04V,and the current density is increased approximately by 2 orders of magnitude.Thus,the nano Ni-B microelectrode has very strong electrocatalytic activity for the oxidation of methanol.The kinetic parameters were determined with the steady polarization curves.The results show that the rate constants for both the oxidation of Ni(Ⅱ) to Ni(Ⅲ) and the reduction of Ni(Ⅲ) to Ni(Ⅱ) at the nano Ni-B microelectrode are elevated by about the 3 orders of magnitude,while the rate constant for the oxidation of methanol by Ni(Ⅲ) is increased by around the 2 orders of magnitude,in comparison with the highly preferred orientation(220) nickel electrode.
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