Ni-S-Co涂层电极的制备及其电化学性能的研究

Preparation and electrochemical properties of Ni-S-Co coating electrode

采用电沉积的方法以泡沫镍为基体制备出非晶Ni-S-Co合金电极。用电化学测试方法分析涂层的电化学行为。结果表明,较好的制备涂层电极条件为:CoSO4.7H2O掺杂浓度为10g/L,电流密度为50mA/cm2,温度为50℃,电沉积时间为40min,pH值为4。当电解电流密度为1200A/m2时,非晶Ni-S-Co合金电极的极化电位较非晶Ni-S合金电极低95mV,较Ni金属电极低405mV;根据Tafel曲线计算出Ni、非晶Ni-S以及非晶Ni-S-Co电极的表面活化能分别为49.5、40.3和38.6kJ/mol。Ni-S-Co电极具有更高的交换电流密度和更低的析氢活化能,因此具有更高的析氢催化活性。

Amorphous Ni-S-Co alloy has been prepared on the foam nickel matrix by chemical electro-deposition method. The optimal conditions for electrodeposition has been determined by electrochemical methods. 10g/L in COSO4 · 7HzO doping content, 50mA/cm^2 in current density, 50℃ in temperature, 40min. in deposition time, 4 in pH value. The HER overpotential of the amorphous Ni-S-Co alloy was 95 and 405mV lower than that of amorphous Ni-S alloy and nickel metal at current density of 1200A/m^2, respectively. The surface activition energy can be calculated from Tafel curves. 49.5kJ/mol for nickel electrode,40. 3kJ/mol for Ni-S amorphous electrode and 38.6kJ/mol for amorphous Ni-S-Co electrode. The Ni-S-Co alloy is more active with lower potential for hydrogen evolution, higher exchange current density and lower activation energy compared with Ni and Ni-S electrode. The hydrogen evolution reaction （HER） is enhanced.