Nickel is a promising electrocatalyst of hydrogen electrode reaction in alkaline media. Its electrocatalytic activity for hydrogen oxidation and evolution reactions can be enhanced when its surface is partially covered by Ni (hydr)oxides or by associating Ni with Cu. In this work, the influence of the NaOH concentration on the hydrogen electrode kinetics on various Ni electrodes is investigated. On metallic Ni, the electrocatalytic activity is almost constant between pH 12 and 14, while it decreases by a factor two on partially oxidized Ni and NiCu electrode constant when the pH decreases from 14 to 12. Analyzing the current potential curves with the help of microkinetic modeling reveals that the Had and OHad binding energies on Ni do not depend on the pH while the rate constant of the Volmer and Heyrovsky reactions decrease with the pH. The pH effect on the electron transfer elementary act is briefly discussed in the framework of a quantum mechanical theory.

中文翻译：

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NaOH浓度对Ni和NiCu电极氢电极反应动力学的影响

镍是一种在碱性介质中氢电极反应有希望的电催化剂。当其表面部分被氧化镍（Ni）或与铜缔合时，可增强其对氢氧化和放出反应的电催化活性。在这项工作中，研究了NaOH浓度对各种Ni电极上氢电极动力学的影响。在金属Ni上，电催化活性在pH 12和14之间几乎恒定，而在部分氧化的Ni和NiCu电极上，当pH从14降低到12时，其电催化活性降低了两倍。借助微动力学分析电流势曲线模拟表明，Ni上的Had和OHad结合能不依赖于pH，而Volmer和Heyrovsky反应的速率常数随pH降低。