气候变化领域集成服务门户(CCPortal): Geometric distortions in nickel (oxy)hydroxide electrocatalysts by redox inactive iron ions

CCPortal

DOI	10.1039/c8ee01063c
	Geometric distortions in nickel (oxy)hydroxide electrocatalysts by redox inactive iron ions
	Smith R.D.L.; Pasquini C.; Loos S.; Chernev P.; Klingan K.; Kubella P.; Mohammadi M.R.; González-Flores D.; Dau H.
发表日期	2018
ISSN	17545692
起始页码	2476
结束页码	2485
卷号	11 期号:9
英文摘要	The dramatic change in electrochemical behavior of nickel (oxy)hydroxide films upon incorporation of Fe ions provides an opportunity to establish effective electrocatalyst design principles. We characterize a photochemically deposited series of Fe-Ni (oxy)hydroxides by X-ray absorption spectroscopy and track the voltage- and composition-dependence of structural motifs. We observe a trigonal distortion in di-μ-hydroxo bridged NiII-NiII motifs that is preserved following a symmetric contraction of Ni-O bond lengths when oxidized to di-μ-oxo NiIV-NiIV. Incorporation of Fe ions into the structure generates di-μ-hydroxo NiII-FeIII motifs in which Ni-Fe distances are dependent on nickel oxidation state, but Fe-O bond lengths are not. This asymmetry minimizes the trigonal distortion in di-μ-hydroxo NiII-FeIII motifs and neighboring di-μ-hydroxo NiII-NiII sites in the reduced state, but exacerbates it in the oxidized state. We attribute both the Fe-induced anodic shift in nickel-based redox peaks and the improved ability to catalyze the oxygen evolution reaction to this inversion in geometric distortions. Spectroelectrochemical experiments reveal a previously unreported change in optical absorbance at ca. 1.5 V vs. RHE in Fe-containing samples. We attribute this feature to oxidation of nickel ions in di-μ-hydroxo NiII-FeIII motifs, which we propose is the process relevant to catalytic oxygen evolution. © 2018 The Royal Society of Chemistry.
英文关键词	Binary alloys; Bond length; Catalytic oxidation; Electrocatalysts; Metal ions; Oxidation; Oxygen; Spectroelectrochemistry; X ray absorption spectroscopy; Catalytic oxygen evolution; Composition dependence; Electrochemical behaviors; Geometric distortion; Optical absorbance; Oxygen evolution reaction; Spectroelectrochemical; Trigonal distortion; Nickel compounds
语种	英语
来源期刊	Energy & Environmental Science
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/190125
作者单位	FB Physik, Freie Universität Berlin, Arnimallee 14, Berlin, 14195, Germany; Department of Chemistry, University of Waterloo, 200 University Ave. W, Waterloo, ON N2L 3G1, Canada; Fraunhofer Institute for Manufacturing Technology, Advanced Materials IFAM, Branch Lab Dresden, Winterbergstraße 28, Dresden, 01277, Germany
推荐引用方式 GB/T 7714	Smith R.D.L.,Pasquini C.,Loos S.,et al. Geometric distortions in nickel (oxy)hydroxide electrocatalysts by redox inactive iron ions[J],2018,11(9).
APA	Smith R.D.L..,Pasquini C..,Loos S..,Chernev P..,Klingan K..,...&Dau H..(2018).Geometric distortions in nickel (oxy)hydroxide electrocatalysts by redox inactive iron ions.Energy & Environmental Science,11(9).
MLA	Smith R.D.L.,et al."Geometric distortions in nickel (oxy)hydroxide electrocatalysts by redox inactive iron ions".Energy & Environmental Science 11.9(2018).