Electrochemical Oxide Growth on Nickel and Commercial Nickel Alloys: Influence of Chromium and Molybdenum
Electrochemical Oxide Growth on Nickel and Commercial Nickel Alloys: Influence of Chromium and Molybdenum
复制标题
镍和商用镍合金上的电化学氧化物生长：铬和钼的影响
DOI：
10.1149/1945-7111/acd7a6
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发表时间：
2023
影响因子：
3.9
通讯作者：
Stuve, Eric M.
中科院分区：
文献类型：
--
作者：
Kretzmer, Isaac;Stuve, Eric M.
镍-铬-钼（NiCrMo）合金因具有优异的耐腐蚀性而众所周知，但其电催化性能尚未得到广泛研究。本文研究了G35、B3和C276合金在25 ℃碱性电解液中电活性氢氧化镍（NiOOH）相的形成和析氧反应动力学。可再生的氧化物层通过在0.85和1.52 V之间相对于RHE的电位循环生长高达600个循环，并且通过循环伏安法自始至终监测Ni（OH）2和NiOOH之间的转变。在270和390 mV之间的OER超电位下测量起始电位、Tafel斜率和转换频率（TOF）。具有不同Cr的合金：Mo比率具有显著更高的电化学表面积和增加的γ-NiOOH形成，表明更高的金属溶解速率。相等的Cr：Mo浓度合金和纯Ni形成了主要的β-NiOOH表面，并且具有比含有大量γ-NiOOH的那些大1.8-2.0倍的TOF值。NiCrMo合金需要较小的过电位（54-80 mV）来产生10 mA cm− 2的OER电流，并且具有与纯Ni相当的塔菲尔斜率。本文的研究结果表明，β-NiOOOH开发的表面比γ-NiOOOH开发的表面具有更高的OER活性，并表明某些NiCrMo合金具有作为OER电催化剂的前景。
Nickel-chromium-molybdenum (NiCrMo) alloys are well-known for having exceptional corrosion resistance, but their electrocatalytic properties have not been extensively studied. In this paper, the development of electro-active nickel-oxyhydroxide (NiOOH) phases and kinetics of the oxygen evolution reaction (OER) have been examined on alloys G35, B3, and C276 in alkaline electrolyte at 25 C. Reproducible oxide layers were grown by potential cycling between 0.85 and 1.52 V vs RHE up to 600 cycles, and the transition between Ni (OH) 2 and NiOOH was monitored by cyclic voltammetry throughout. Onset potentials, Tafel slopes, and turnover frequencies (TOF) were measured at OER overpotentials between 270 and 390 mV. Alloys with dissimilar Cr: Mo ratios had significantly higher electrochemical surface area and increased γ-NiOOH formation, suggesting higher metal dissolution rates. The equal Cr: Mo concentration alloy and pure Ni developed a primarily β-NiOOH surface, and had 1.8–2.0 times larger TOF values than those containing significant γ-NiOOH. The NiCrMo alloys required smaller overpotentials (54–80 mV) to produce 10 mA cm− 2 of OER current, and had comparable Tafel slopes to pure Ni. The findings here indicate a β-NiOOH-developed surface to be more OER-active than a γ-NiOOH-developed surface, and suggest certain NiCrMo alloys have promise as OER electrocatalysts.