Formation of Highly Active NiO(OH) Thin Films from Electrochemically Deposited Ni(OH)2 by a Simple Thermal Treatment at a Moderate Temperature: A Combined Electrochemical and Surface Science Investigation
发布时间：2022-01-12
点击次数：
影响因子：13.08
DOI码：10.1021/acscatal.1c04589
发表刊物：ACS Catalysis
关键字：nickel hydroxides electrocatalysis oxygen evolution reaction Raman spectroscopy X-ray photoelectron spectroscopy
摘要：Electrodeposited α-Ni(OH)2 thin films on Ti substrates were investigated as electrocatalysts for cost-effective water-splitting devices. A facile annealing of the α-Ni(OH)2 films at 150 °C for 1 h is of extreme importance to enhance their electrocatalytic activity for the oxygen evolution reaction (OER). Voltammetric analysis combined with X-ray photoelectron spectroscopy (XPS), Raman spectroscopy, and scanning electron microscopy (SEM) reveals that the induced structural evolution of the α-Ni(OH)2 results in a strong improvement of electrical conductivity, which is a crucial factor for the highly enhanced activity. Moreover, the annealing accelerates the generation of active sites, which can even be further improved easily via electrochemical galvanostatic conditioning. Thus, the α-Ni(OH)2 thin films exhibit an overpotential of 310 mV (at j = 10 mA cm–2) with a Tafel slope of 42.6 mV dec–1 in 1.0 M KOH, which is much better than that for a commercial RuO2/Ti electrode. The active component at the applied electrode potential of 10 mA cm–2 is characterized to be γ-Ni2.63O0.63(OH)1.37 showing an “apparent oxidation state” of +2.63 for the Ni. In addition, the annealed electrocatalyst exhibits only a negligible overpotential increase after 26 h of measurement. The overpotential even decreases to 292 mV in the first 3 h, demonstrating outstanding electrocatalytic activity and long-term stability.
合写作者：Wolfram Jaegermann
第一作者：Shasha Tao
论文类型：期刊论文
通讯作者：Qingbo Wen, Bernhard Kaiser
学科门类：工学
一级学科：材料科学与工程
文献类型：J
卷号：12
页面范围：1508-1519
是否译文：否
发表时间：2022-01-11
收录刊物：SCI
发布期刊链接：https://pubs.acs.org/doi/full/10.1021/acscatal.1c04589