Characteristics of NiO present in solids obtained from hydrotalcites based on Ni/Al and Ni-Zn/Al

NiO has a variety of applications, mainly in the production of electrochemical sensors and of metallic nickel. In addition, it is widely used as catalysts to produce hydrogen from natural gas. In this work, hydrotalcites based on nickel-aluminum and nickel-zinc-aluminum were synthesized, calcined at 500 °C and studied by different techniques. It was observed that nickel-aluminum hydrotalcites are thermally more stable, collapsing at higher temperatures than hydrotalcites containing zinc. During calcination, aluminum is incorporated into NiO lattice, leading to a decrease in crystallographic parameters. However, zinc decreases this effect, favoring the formation of NiO with lattice parameters close to pure nickel oxide. Zinc also contributes to the formation of smaller NiO particles, which is very useful for its use as a catalyst. In addition, aluminum led to a distortion in NiO lattice, an effect that is minimized by zinc, showing that it hinders the incorporation of Al3+ in the NiO lattice.

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HREM observation of NiO growth on submicron spheres of pure nickel

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100154718 ◽

1989 ◽

Vol 47 ◽

pp. 548-549

Author(s):

C.M. Teng ◽

T.F. Kelly ◽

J.P. Zhang ◽

H.M. Lin ◽

Y.W. Kim

Keyword(s):

Nickel Oxide ◽

Grain Boundaries ◽

Pure Nickel ◽

Submicron Particles ◽

Crystal Formation ◽

Nickel Wire ◽

Liquid Droplets ◽

Oxide Interface ◽

Nickel Chromium ◽

Chromium Alloys

Spherical submicron particles of materials produced by electrohydrodynamic (EHD) atomization have been used to study a variety of materials processes including nucleation of alternative crystallization phases in iron-nickel and nickel-chromium alloys, amorphous solidification in submicron droplets of pure metals, and quasi-crystal formation in nickel-chromium alloys. Some experiments on pure nickel, nickel oxide single crystals, the nickel/nickel(II) oxide interface, and grain boundaries in nickel monoxide have been performed by STEM. For these latter studies, HREM is the most direct approach to obtain particle crystal structures at the atomic level. Grain boundaries in nickel oxide have also been investigated by HREM. In this paper, we present preliminary results of HREM observations of NiO growth on submicron spheres of pure nickel.Small particles of pure nickel were prepared by EHD atomization. For the study of pure nickel, 0.5 mm diameter pure nickel wire (99.9975%) is sprayed directly in the EHD process. The liquid droplets solidify in free-flight through a vacuum chamber operated at about 10-7 torr.

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Atomic Layer Deposition of Ni-Co-O Thin-Film Electrodes for Solid-State LIBs and the Influence of Chemical Composition on Overcapacity

Nanomaterials ◽

10.3390/nano11040907 ◽

2021 ◽

Vol 11 (4) ◽

pp. 907

Author(s):

Yury Koshtyal ◽

Ilya Mitrofanov ◽

Denis Nazarov ◽

Oleg Medvedev ◽

Artem Kim ◽

...

Keyword(s):

Chemical Composition ◽

Atomic Layer Deposition ◽

Nickel Oxide ◽

Cobalt Oxide ◽

Lithium Ion ◽

Atomic Layer ◽

Metallic Nickel ◽

Uniform Density ◽

Oxide Content ◽

Layer Deposition

Nanostructured metal oxides (MOs) demonstrate good electrochemical properties and are regarded as promising anode materials for high-performance lithium-ion batteries (LIBs). The capacity of nickel-cobalt oxides-based materials is among the highest for binary transition metals oxide (TMOs). In the present paper, we report the investigation of Ni-Co-O (NCO) thin films obtained by atomic layer deposition (ALD) using nickel and cobalt metallocenes in a combination with oxygen plasma. The formation of NCO films with different ratios of Ni and Co was provided by ALD cycles leading to the formation of nickel oxide (a) and cobalt oxide (b) in one supercycle (linear combination of a and b cycles). The film thickness was set by the number of supercycles. The synthesized films had a uniform chemical composition over the depth with an admixture of metallic nickel and carbon up to 4 at.%. All samples were characterized by a single NixCo1-xO phase with a cubic face-centered lattice and a uniform density. The surface of the NCO films was uniform, with rare inclusions of nanoparticles 15–30 nm in diameter. The growth rates of all films on steel were higher than those on silicon substrates, and this difference increased with increasing cobalt concentration in the films. In this paper, we propose a method for processing cyclic voltammetry curves for revealing the influence of individual components (nickel oxide, cobalt oxide and solid electrolyte interface—SEI) on the electrochemical capacity. The initial capacity of NCO films was augmented with an increase of nickel oxide content.

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Membrane-Based Electrochemical Sensors for Detecting Internal Corrosion Risk of Natural Gas Pipelines

ECS Meeting Abstracts ◽

10.1149/ma2020-01282140mtgabs ◽

2020 ◽

Vol MA2020-01 (28) ◽

pp. 2140-2140

Author(s):

Margaret Ziomek-Moroz ◽

Timothy Duffy ◽

Derek M. Hall ◽

Serguei N. Lvov

Keyword(s):

Natural Gas ◽

Electrochemical Sensors ◽

Gas Pipelines ◽

Internal Corrosion ◽

Natural Gas Pipelines ◽

Corrosion Risk

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The Ni-Al-Hf Multiphase Diffusion

Archives of Metallurgy and Materials ◽

10.1515/amm-2016-0100 ◽

2016 ◽

Vol 61 (2) ◽

pp. 587-592 ◽

Cited By ~ 1

Author(s):

J. Romanowska ◽

B. Wierzba ◽

J. Markowski ◽

M. Zagula-Yavorska ◽

J. Sieniawski

Keyword(s):

Diffusion Coefficients ◽

Thermodynamic Data ◽

Pure Nickel ◽

Experimental Results ◽

Nickel Aluminum ◽

Aluminide Coatings ◽

Multiphase Diffusion

Abstract The generalized Darken method was applied to simulate the diffusion between γ-Ni| γ’-Ni3Al and γ’-Ni3Al|β-NiAl interfaces. The results of calculations were compared with the experimental concentration’s profiles of nickel, aluminum and hafnium in aluminide and hafnium doped aluminide coatings deposited by the CVD and PVD methods on pure nickel. The method deals with the Wagner’s integral diffusion coefficients and thermodynamic data - activities of components. The experimental results agree with the simulated ones.

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Easy Method for the Transformation of Levulinic Acid into Gamma-Valerolactone Using a Nickel Catalyst Derived from Nanocasted Nickel Oxide

Materials ◽

10.3390/ma12182918 ◽

2019 ◽

Vol 12 (18) ◽

pp. 2918 ◽

Cited By ~ 3

Author(s):

Sanchis ◽

García ◽

Dejoz ◽

Vázquez ◽

Llopis ◽

...

Keyword(s):

High Temperature ◽

Nickel Oxide ◽

Hydrothermal Method ◽

Nickel Catalyst ◽

Levulinic Acid ◽

Nickel Catalysts ◽

Metallic Nickel ◽

Easy Method ◽

High Temperature Water ◽

Temperature Water

Different nickel catalysts have been tested for the transformation of levulinic acid into γ-valerolactone using an easy hydrothermal method, taking advantage of the properties of the high temperature water. A metallic nickel catalyst derived from NiO synthesized by a nanocasting procedure can achieve a productivity to γ-valerolactone, which is two orders of magnitude higher than that obtained by a commercial nickel catalyst. This nanocasted metallic nickel catalyst has shown bifunctionality as it is capable of activating water as the source for hydrogen and undertaking the further hydrogenation step. In contrast with metallic nickel, nickel oxide has shown to be incapable of transforming levulinic acid into γ-valerolactone.

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