The solubility of nickel in nickel ferrite

doi:10.1016/0022-3697(61)90213-X

Journal of Physics and Chemistry of Solids

Volume 21, Issues 1–2, October 1961, Pages 76-80

https://doi.org/10.1016/0022-3697(61)90213-X Get rights and content

Abstract

A method is described for preparing high resistivity nickel ferrites with nickel excess. High resistivity materials can be made by suppressing Fe⁺⁺ and Ni⁺⁺⁺ ions in the spinel lattice by suitable heat treatment. Electrical measurements indicate that excess nickel dissolves in the ferrite lattice up to a nickel to iron ratio of 1.029: 2. This result is consistent with available data of saturation magnetic moment.

References (8)

G.H. Jonker
J. Phys. Chem. Solids
(1959)
R. Derry et al.
A.R.L. Report R1/100
(1956)
K. Kamiyoshi
Sci. Rep. Res. Inst. Tahoku Univ.
(1951)
L.G. van Uitert
J. Chem. Phys.
(1955)

There are more references available in the full text version of this article.

Cited by (7)

Evolution of lattice defects in nickel ferrite spinel: Oxygen vacancy and cation substitution
2022, Journal of Alloys and Compounds
Citation Excerpt :
The increased concentration of oxygen vacancies also promoted the diffusion of atoms and the growth of sintering neck. In general, oxygen vacancies and low-valent cations are simultaneously present in oxygen-deficient nickel ferrite, regardless of whether NiFe2O4-δ decomposes or not [9]. The XPS analysis was used to identify the chemical states of the NiFe2O4-δ samples sintered at different temperature.
Oxygen deficiency is a common phenomenon in the sintering process of nickel ferrite spinel, and has a significant impact on the properties of the NiFe₂O₄ sintered body. This work investigated the effects of oxygen deficiency on the evolution of the lattice defects in spinel crystal. The oxygen deficiency led to the generation of a non-stoichiometric nickel ferrite containing oxygen vacancies (NiFe₂O_4-δ). As the sintering temperature increased from 1150 °C to 1400 °C, the concentration of oxygen vacancies in NiFe₂O_4-δ increased, with a δ value increasing from 0.0014 to 0.0355 and a lattice parameter increasing from 8.3485 to 8.3567 Å. X-ray photoelectron (XPS), Fourier transform infrared (FTIR) and Raman spectroscopy all showed that the crystal structure of NiFe₂O_4-δ belonged to the Fd3m space group with Fe²⁺ ions partially replacing Fe³⁺ in the octahedral sites. Furthermore, a tendency for NiFe₂O_4-δ to decompose to Ni alloy and Fe₃O₄ during sintering could be observed.
Nickel Spinel Ferrites: A review
2021, Journal of Magnetism and Magnetic Materials
Spinel ferrite is a class of magnetic materials which derives this name due to its similarity with the naturally occurring $Mg {Al}_{2} O_{4}$ mineral. Also known by the name of ‘cubic ferrites’, these ferrites have been the center of attraction for material scientists ever since their discovery. Among these spinel ferrites, nickel ferrites have become one of the best options for usage in different applications such as medical treatment, electronic devices, electromagnetic wave absorption materials and water purification. The popularity of these ferrites is due to their favourable properties such as high permeability, high resistivity and high saturation magnetization.
The purpose of writing this review paper is to summarize the major researches in the field of nickel ferrites on one platform. The major research findings are tabulated and briefly summarized. The review paper is divided into four major sections. The first section, “Introduction to spinel ferrites”, presents different types of magnetic behaviors, the classification of ferrites, and a brief introduction to spinel ferrites and their structures. The second section, “Nickel spinel ferrites”, briefly describes nickel spinel ferrites, their possible applications, and different methods of their synthesis. The third section, named as “Different dopings in nickel spinel ferrites”, outlines the major research attempts in the field of nickel ferrites and their derivatives. The final and fourth section, “Different properties of nickel ferrites”, summarizes the major properties of nickel ferrites, which have been commonly studied.
Influence of thermal processing on magnetotransport characteristics of NdSr<inf>2</inf>Mn<inf>2</inf>O<inf>7+</inf><inf>δ</inf>
2015, Materials Research Bulletin
Citation Excerpt :
It has been established [11–18] that oxygen non-stoichiometry for major systems can be modified by means of the isothermal annealing of samples under controlled partial oxygen pressure. Besides, it was found that electrical conductivity [12–18] and magnetic properties [11,19,20] of the materials are extremely sensitive to different oxygen content. In this study a number of NdSr2Mn2O7+δ samples were synthesized subjected to various thermal processing in air atmosphere.
Influence of oxygen non-stoichiometry on magnetic and electric properties of the compounds has not almost been studied yet.
Synthesis of a number of the NdSr₂Mn₂O_7+δ samples subjected to various thermal processing in air atmosphere and investigation of their structure, oxygen non-stoichiometry, electrical and magnetic properties.
The compounds obtained have been characterized by using X-ray diffraction (XRD) analysis, a modified gravimetric method, vibrating sample magnetometry (VSM) and standard DC four-probe method.
It was established that additional firing of the samples at different temperatures leads to essential changes in the oxygen non-stoichiometry. The noticeable magnetoresistance (MR) effect is observed for all the compounds below 200 K and increases monotonically as the temperature decreases. The MR values for the compounds as a function of oxygen content vary nonlinearly. The largest MR value of 380% at the 5 K and magnetic field of 7 T was achieved for the sample with the oxygen non-stoichiometry of δ = 0.03.
The results observed are discussed in the assumption of ferromagnetic cluster formation in the compounds.
Catalytic properties of some mixed transition-metal oxides
1991, Materials Letters
The effect of preparation procedure of some mixed transition-metal oxides on their catalytic properties has been investigated. The catalytic activity of the oxides, attributed to their n- or p-semiconductive character, was also studied with regard to the reaction of thermal decomposition of potassium and sodium chlorates and perchlorates. The oxides studied were the nickel spinel ferrites and the erbium-iron garnets and perovskites (orthoferrites) and it was found that catalytic activity depends on their preparation procedure. Materials mainly consisting of the spinel or perovskite and garnet phases, present increased catalytic activity.
Oxide spinels
1982, Handbook of Ferromagnetic Materials
This chapter discusses the crystal structure, chemistry, and magnetic properties of oxide spinels. The spinel structure is one of the most frequently encountered with the MM′₂X₄ compounds. X represents oxygen or some chalcogenic bivalent anion that may be partly substituted by proper monovalent anions; M, M′ are metallic ions whose valencies have to fulfil the electroneutrality requirements. Because of the large electronegativity of oxygen, the ionic type of bonds prevails in almost all oxide spinels. Therefore, the electrical resistivity is usually high and allows classifying the compounds as insulators even though sometimes the term low-mobility semiconductors would apply. The spinel structure is called after the mineral spinel MgAl₂0₄. It is formed by a nearly close-packed fcc array of anions with holes partly filled by the cations. There are two kinds of holes differing in coordination: tetrahedral and octahedral. From all these sites available in the elementary cube containing 32 anions, only eight of the tetrahedral and 16 of the octahedral are occupied by cations. The oxide spinels may usually be prepared at elevated temperatures by a direct solid-state reaction among the simple oxides. The relevant temperature range is about 800 to 1500 °C, depending on the type of cations.
Effect of Off-Stoichiometry on Electrical Conductivity in Ni-Fe and Mn-Co Spinel Systems
2020, Journal of the Electrochemical Society

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^∗: Present address: Denbighshire Technical College, Wrexham.

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The solubility of nickel in nickel ferrite

Abstract

J. Phys. Chem. Solids

A.R.L. Report R1/100

Sci. Rep. Res. Inst. Tahoku Univ.

J. Chem. Phys.