Spectroscopic ellipsometry study of nickel oxidation in alkaline solution

Souza, L.M.M. de; Kong, Fanping; McLarnon, Frank; Müller, Rolf

doi:10.1016/s0013-4686(96)00298-8

Cited by 60 publications

(46 citation statements)

References 25 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Ni(OH) 2 also forms electrochemically on Ni electrodes in alkaline media, which has importance for the development of Ni-based electrocatalysts [23,105,179,[184][185][186][187]. Consequently, the surface electrochemistry has been extensively studied using atomic force microscopy [188], ellipsometry [181,[189][190][191], IR spectroscopy [192], Raman spectroscopy [166,193,194], UV-Vis spectroscopy [192,195], voltammetry [179,185,[196][197][198][199][200][201], X-ray scattering [176], XPS [179,202] and gravimetry with an electrochemical quartz crystal microbalance [203,204]. During a forward voltammetric sweep, a surface bilayer of α-Ni(OH) 2 underlaid by NiO x forms initially [179].…”

Section: (D) Chemical Ageingmentioning

confidence: 99%

See 1 more Smart Citation

Nickel hydroxides and related materials: a review of their structures, synthesis and properties

et al. 2015

View full text Add to dashboard Cite

This review article summarizes the last few decades of research on nickel hydroxide, an important material in physics and chemistry, that has many applications in engineering including, significantly, batteries. First, the structures of the two known polymorphs, denoted as α-Ni(OH) 2 and β-Ni(OH) 2 , are described. The various types of disorder, which are frequently present in nickel hydroxide materials, are discussed including hydration, stacking fault disorder, mechanical stresses and the incorporation of ionic impurities. Several related materials are discussed, including intercalated α-derivatives and basic nickel salts. Next, a number of methods to prepare, or synthesize, nickel hydroxides are summarized, including chemical precipitation, electrochemical precipitation, sol-gel synthesis, chemical ageing, hydrothermal and solvothermal synthesis, electrochemical oxidation, microwaveassisted synthesis, and sonochemical methods. Finally, the known physical properties of the nickel hydroxides are reviewed, including their magnetic, vibrational, optical, electrical and mechanical properties. The last section in this paper is intended to serve as a summary of both the potentially useful properties of these materials and the methods for the identification and characterization of 'unknown' nickel hydroxide-based samples.

show abstract

Section: (D) Chemical Ageingmentioning

confidence: 99%

“…They found that during a positive scan in 1 M KOH starting at 0 V versus RHE, a thin film of Ni(OH) 2 is formed at E ∼ 0. [189]. Adapted from [189], with permission from Elsevier.…”

Section: (Iv) Ellipsometrymentioning

confidence: 99%

Nickel hydroxides and related materials: a review of their structures, synthesis and properties

et al. 2015

View full text Add to dashboard Cite

show abstract

“…In an ellipsometric study de Souza et al 213 found that the first layer of oxide formed at potentials close to the lower anodic peak A1 consists of NiO. However this becomes covered with a thick film of Ni(OH) 2 upon further increase of potential.…”

Section: Interfacial Redox Chemistry Of Nickel Based Electrodes In Almentioning

confidence: 99%

“…The voltammetric behaviour of polycrystalline Ni electrodes has been studied by a number of authors including Seghiouer and coworkers, 210 Burke et al, 177,211 Visscher and Barendrecht, 212 de Souza et al, 213 and Simpraga and Conway 214 to name but a few. Typical voltammetric profiles in 1.0 M NaOH for a polycrystalline Ni electrode and a polycrystalline Ni electrode which has been subjected to a repetitive potential cycling regime are presented in Fig.…”

Section: Interfacial Redox Chemistry Of Nickel Based Electrodes In Almentioning

confidence: 99%

Redox and electrochemical water splitting catalytic properties of hydrated metal oxide modified electrodes

Doyle

Godwin

Brandon

et al. 2013

Phys. Chem. Chem. Phys.

521

565

View full text Add to dashboard Cite

This paper presents a review of the redox and electrocatalytic properties of transition metal oxide electrodes, paying particular attention to the oxygen evolution reaction. Metal oxide materials may be prepared using a variety of methods, resulting in a diverse range of redox and electrocatalytic properties. Here we describe the most common synthetic routes and the important factors relevant to their preparation. The redox and electrocatalytic properties of the resulting oxide layers are ascribed to the presence of extended networks of hydrated surface bound oxymetal complexes termed surfaquo groups. This interpretation presents a possible unifying concept in water oxidation catalysis -bridging the fields of heterogeneous electrocatalysis and homogeneous molecular catalysis. In contextOver the past 50 years considerable research efforts have been devoted to the realisation of efficient, economical and renewable energy sources. Metal oxide materials have played a large part in this drive with demonstrated applications at both the research and commercial level. Their use in areas such as batteries, fuel cells and water electrolysis has resulted in the development of materials with a diverse range of structural and chemical properties. In all cases, understanding the fundamental electrochemistry of the material can be invaluable for rational design and optimisation. This review focuses on the redox, charge transport and electrocatalytic properties of transition metal oxide electrodes as they pertain to the electrolytic splitting of water. Particular emphasis is placed on the nature of the active surface which is interpreted in terms of hydrated interlinked oxymetal complexes termed surfaquo groups. In this way, the review seeks to bridge the gap between heterogeneous electrocatalysis and homogeneous molecular catalysis for water oxidation, areas of considerable modern interest and activity.

show abstract

“…The true map of phases and their transformations is likely to be more complex [8] based on recent research [8,[14][15][16][17][18][19]. For example, raman spectroscopy suggests that at the onset of oxygen evolution, NiOOH transforms to another phase [15] and similarly our cyclic voltammetry work suggested that after extensive oxygen evolution (at least 40 hours at 50 mA cm -2 ) an additional phase forms [8].…”

Section: Introductionmentioning

confidence: 80%

Electrocatalytic oxygen evolution on nickel oxy-hydroxide anodes: Improvement through rejuvenation

Mellsop

Gardiner

Marshall

2015

Electrochimica Acta

View full text Add to dashboard Cite

The ageing and rejuvenation behaviour of nickel oxy-hydroxide anodes for alkaline water electrolysis is investigated. The anodically formed oxy-hydroxide material is known to age over time causing a decrease in performance. However, this deactivation can be mitigated by temporarily reducing the potential for brief periods. This work looks at continuous rejuvenation of nickel anodes in 30wt.% KOH solution and it is shown that rejuvenation at 0.5 V vs. HgHgO for 10 minutes every 100 minutes can prevent ageing of the anode, thus maintaining a low overpotential during galvanostatic oxygen evolution at 50 mA cm -2 . It is suggested that the short potentiostatic rejuvenation periods at regular intervals prevents the ratio of Ni(IV) to Ni(III) from increasing, thereby maintaining the intrinsic activity of the material. The rejuvenation potential must be above 0.36 V vs. HgHgO to ensure it is effective in obtaining good performance (i.e. the material must not reduce to Ni(II)). These findings suggest that electrolysis systems using nickel anodes could benefit from direct coupling to fluctuating power sources such as solar or wind, where the variability in their power output could facilitate the rejuvenation of the nickel anode. We estimate that by using the rejuvenation steps, an energy saving of 9% is possible in an alkaline water electrolyser using nickel anodes.

show abstract

Spectroscopic ellipsometry study of nickel oxidation in alkaline solution

Cited by 60 publications

References 25 publications

Nickel hydroxides and related materials: a review of their structures, synthesis and properties

Nickel hydroxides and related materials: a review of their structures, synthesis and properties

Redox and electrochemical water splitting catalytic properties of hydrated metal oxide modified electrodes

Electrocatalytic oxygen evolution on nickel oxy-hydroxide anodes: Improvement through rejuvenation

Contact Info

Product

Resources

About