Synthesis and Properties of Ferrite-Based Nanoparticles

Abstract

The work is dedicated to the study of the structural and optical characteristics, as well as the phase transformations, of ferrite nanoparticles of CeO2-Fe2O3. To characterize the results obtained, the methods of scanning and transmission microscopy, X-ray diffraction (XRD) spectroscopy, and Mössbauer spectroscopy were applied. It was found that the initial nanoparticles are polycrystalline structures based on cerium oxide with the presence of X-ray amorphous inclusions in the structure, which are characteristic of iron oxide. The study determined the dynamics of phase and structural transformations, as well as the appearance of a magnetic texture depending on the annealing temperature. According to the Mossbauer spectroscopy data, it has been established that a rise in the annealing temperature gives rise to an ordering of the magnetic properties and a decrease in the concentration of cationic and vacancy defects in the structure. During the life test of synthesized nanoparticles as cathode materials for lithium-ion batteries, the dependences of the cathode lifetime on the phase composition of nanoparticles were established. It is established that the appearance of a magnetic component in the structure result in a growth in the resource lifetime and the number of operating cycles. The results show the prospects of using these nanoparticles as the basis for lithium-ion batteries, and the simplicity of synthesis and the ability to control phase transformations opens up the possibility of scalable production of these nanoparticles for cathode materials.

Evaluation of the Efficiency of Detection and Capture of Manganese in Aqueous Solutions of FeCeOx Nanocomposites Doped with Nb2O5

“…The synthesis of nanocomposites was carried out in two stages, including the chemical deposition of FeCeO x (which is a mixture of two phases Fe 2 O 3 and CeO 2 ) [ 26 ] and subsequent mechanochemical mixing of amorphous-like FeCeO x nanoparticles with Nb 2 O 5 nanoparticles in the set stoichiometric proportions and thermal annealing in the air atmosphere at a temperature of 1000 °C within 8 h.…”

“…The samples were cooled down together with a muffle furnace (Naberthetm, Bremen, Germany) for 24 h. The choice of the annealing temperature is due to phase transformations in FeCeO х nanoparticles with the formation of two stable phases Fe 2 O 3 and CeO 2 . Earlier in [ 26 ], we examined in detail the phase transformations of FeCeO х nanoparticles as a result of thermal annealing in the temperature range from 400 to 800 °C, according to which, when the annealing temperature is increased above 600 °C, the structure of nanoparticles is a mixture of two phases Fe 2 O 3 and CeO 2 . In this case, an increase in temperature leads to an increase in the degree of structural ordering and a decrease in distortions and deformations of the crystal lattice.…”

Preparation of Cotton Linters’ Aerogel-Based C/NiFe2O4 Photocatalyst for Efficient Degradation of Methylene Blue

“…In recent years, photocatalysis, as one of the advanced oxidation processes, has provided a promising pathway for solar energy conversion [1], which reserves broad prospects of applications in wastewater treatment, air purification, solar cells, antibacterial agents and many other fields. Current exploration of the highly active photocatalyst functioning in the visible lights has attracted remarkable attention [2][3][4]. Nickel ferrite (NiFe 2 O 4 ) is one of the most interesting ferrites thanks to the dependence of its performance on particle size.…”

A Study on the Applicability of NiFe2O4 Nanoparticles as the Basis of Catalysts for the Purification of Aqueous Media from Pollutants

“…In recent years, much attention has been paid to environmentally friendly methods of producing nanostructured materials and nanoparticles, which have great prospects for use in various fields of technology, including microelectronics, biomedicine, catalytic decomposition of pollutants and dyes [1][2][3]. An important role in such studies is played by spinel structures with a number of unique properties that allow them to be used in a large number of different applications [4][5][6][7][8][9][10].…”