skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Superparamagnetic Particle Size Limit of Mn-Zn Ferrite Nanoparticles Synthesised Through Aqueous Method

Abstract

Mn0.67Zn0.33Fe2O4 nanoparticles with size ranging from 20 to 80 nm have been synthesized using the modified oxidation method. The Curie temperatures for all the samples are found to be within 630 {+-} 5 K suggesting that there is no size-dependent cation distribution. Moessbauer studies on the synthesized nanoparticles suggest that the critical particle size limit for superparamagnetism to be about 25 nm at 293 K.

Authors:
 [1];  [2];  [3]; ; ;  [1]
  1. Graduate School of Environmental Studies, Tohoku University, AramakiAza Aoba-ku, Sendai 980-8579 (Japan)
  2. (India)
  3. Materials Science Centre, Dept. of Nuclear Physics, University of Madras, Guindy Campus, Chennai-25 (India)
Publication Date:
OSTI Identifier:
20798650
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 833; Journal Issue: 1; Conference: 3. international workshop on water dynamics, Sendai (Japan), 16-17 Nov 2005; Other Information: DOI: 10.1063/1.2207067; (c) 2006 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; CATIONS; CURIE POINT; DISTRIBUTION; FERRITES; MANGANESE COMPOUNDS; MOESSBAUER EFFECT; NANOSTRUCTURES; OXIDATION; PARTICLE SIZE; PARTICLES; SUPERPARAMAGNETISM; ZINC COMPOUNDS

Citation Formats

Joseyphus, R. Justin, Materials Science Centre, Dept. of Nuclear Physics, University of Madras, Guindy Campus, Chennai-25, Narayanasamy, A., Jeyadevan, B., Shinoda, K., and Tohji, K. Superparamagnetic Particle Size Limit of Mn-Zn Ferrite Nanoparticles Synthesised Through Aqueous Method. United States: N. p., 2006. Web. doi:10.1063/1.2207067.
Joseyphus, R. Justin, Materials Science Centre, Dept. of Nuclear Physics, University of Madras, Guindy Campus, Chennai-25, Narayanasamy, A., Jeyadevan, B., Shinoda, K., & Tohji, K. Superparamagnetic Particle Size Limit of Mn-Zn Ferrite Nanoparticles Synthesised Through Aqueous Method. United States. doi:10.1063/1.2207067.
Joseyphus, R. Justin, Materials Science Centre, Dept. of Nuclear Physics, University of Madras, Guindy Campus, Chennai-25, Narayanasamy, A., Jeyadevan, B., Shinoda, K., and Tohji, K. Mon . "Superparamagnetic Particle Size Limit of Mn-Zn Ferrite Nanoparticles Synthesised Through Aqueous Method". United States. doi:10.1063/1.2207067.
@article{osti_20798650,
title = {Superparamagnetic Particle Size Limit of Mn-Zn Ferrite Nanoparticles Synthesised Through Aqueous Method},
author = {Joseyphus, R. Justin and Materials Science Centre, Dept. of Nuclear Physics, University of Madras, Guindy Campus, Chennai-25 and Narayanasamy, A. and Jeyadevan, B. and Shinoda, K. and Tohji, K.},
abstractNote = {Mn0.67Zn0.33Fe2O4 nanoparticles with size ranging from 20 to 80 nm have been synthesized using the modified oxidation method. The Curie temperatures for all the samples are found to be within 630 {+-} 5 K suggesting that there is no size-dependent cation distribution. Moessbauer studies on the synthesized nanoparticles suggest that the critical particle size limit for superparamagnetism to be about 25 nm at 293 K.},
doi = {10.1063/1.2207067},
journal = {AIP Conference Proceedings},
number = 1,
volume = 833,
place = {United States},
year = {Mon May 15 00:00:00 EDT 2006},
month = {Mon May 15 00:00:00 EDT 2006}
}
  • Nanoparticles of Mg{sub 0.5}Zn{sub 0.5}Fe{sub 2}O{sub 4} ferrite have been synthesized by co-precipitation method. XRD and Mössbauer spectroscopic results of Mg{sub 0.5}Zn{sub 0.5}Fe{sub 2}O{sub 4} annealed at 200 °C, 500 °C and 800 °C are reported. It was observed that the crystallite size increases and the lattice parameter decreases with increase in annealing temperature. The observed decrease in lattice strain supports the increase in crystallite size. The Mössbauer spectra of the samples annealed at 200 °C and 500 °C exhibits superparamagnetic doublets whereas the Mössbauer spectrum of the sample annealed at 800 °C exhibits paramagnetic doublet along with weak sextetmore » of hyperfine interaction. The values of isomer shift resemble the presence of high spin iron ions. The studied ferrite nanoparticles are suitable for biomedical applications. The results are incorporated employing core-shell model and cation redistribution.« less
  • In this paper, a modified simple solvothermal method is employed to synthesize Mn{sub 3}O{sub 4} nanocrystals using four different solvents: acetone, ethanol, N,N-dimethylformamide (DMF), and dimethyl sulfoxide (DMSO). Mn{sub 3}O{sub 4} nanoparticles with a tetragonal hausmannite nano-structure are characterized by powder X-ray diffraction (XRD), transmission electron microscopy (TEM), high resolution transmission electron microscopy (HRTEM), Fourier transform infrared spectroscopy (FTIR), as well as superconducting quantum interference device magnetometer (SQUID). The Mn{sub 3}O{sub 4} particle size is found to have a strong dependency on the solvent used. A reaction scheme is proposed to understand this dependency, suggesting that the solvent coordinating capabilitymore » has a critical effect on Mn{sub 3}O{sub 4} particle size. The stronger the coordinating capability of the solvent is, the smaller the Mn{sub 3}O{sub 4} particle size is. In addition, magnetic properties of the nano-structured Mn{sub 3}O{sub 4} are also tested and discussed. - Graphical abstract: The comparison of the particle size of Mn{sub 3}O{sub 4} nanoparticles synthesized using different solvents and HRTEM image of Mn{sub 3}O{sub 4} individual nanoparticle revealed its single-crystal nature. - Highlights: • Mn{sub 3}O{sub 4} nanocrystals were synthesized using different solvents by a solvothermal method. • The particle size of Mn{sub 3}O{sub 4} nanocrystal is found to have a strong dependency on the solvent used. • A reaction mechanism is proposed to explain the difference of particle size of Mn{sub 3}O{sub 4} nanocrystals. • Magnetic properties of Mn{sub 3}O{sub 4} nanocrystals with different particle size are tested and compared.« less
  • Highlights: ► TiO{sub 2}/SiO{sub 2}/Mn–Zn ferrite acts as magnetic photocatalyst nanoparticle. ► SiO{sub 2} interlayer is used to prevent electron migration between photocatalyst and magnetic core. ► TiO{sub 2}/Mn–Zn ferrite without SiO{sub 2} interlayer shows poor magnetic and photocatalytic property. -- Abstract: A magnetic photocatalyst, TiO{sub 2}/SiO{sub 2}/Mn–Zn ferrite, was prepared by stepwise synthesis involving the co-precipitation of Mn–Zn ferrite as a magnetic core, followed by a coating of silica as the interlayer, and titania as the top layer. The particle size and distribution of magnetic nanoparticles were found to depend on the addition rate of reagent and dispersing ratemore » of reaction. The X-ray diffractometer and transmission electron microscope were used to examine the crystal structures and the morphologies of the prepared composites. Vibrating sample magnetometer was also used to reveal their superparamagnetic property. The UV–Vis spectrophotometer was employed to monitor the decomposition of methylene blue in the photocatalytic efficient study. It was found that at least a minimum thickness of the silica interlayer around 20 nm was necessary for the inhibition of electron transference initiated by TiO{sub 2} and Mn–Zn ferrite.« less
  • The Mn{sub 0.25}Zn{sub 0.75}Fe{sub 2}O{sub 4} (MZF) nanoparticles of 3 to 5 nm size were synthesized by chemical coprecipitation method. The X-ray diffraction (XRD) patterns were well fitted with single phase spinel ferrite structure using Rietveld analysis as Fd-3m space group. The ferromagnetic resonance (FMR) spectra of MZF nanoparticles becomes more asymmetric with increase in particle size from 3 to 5 nm. The change in FMR line shape is attributed to the increase in ferromagnetic interactions and anisotropy in the system with increase in nanoparticles size. The decrease in total absorption of the FMR line with decreasing temperature at low temperatures indicatesmore » weak antiferromagnetic coupling between the octahedral and tetrahedral sublattices of the spinel ferrite system.« less
  • We have shown that superparamagnetic iron oxide (Fe3O4) nanoparticles with a surface functionalization of dimercaptosuccinic acid is an effective, magnetic, sorbent material for toxic metals such as Hg, Ag, Pb, Cd and other soft cations. The chemical affinity, stability, capacity and kinetics of the functionalized nanoparticles has been explored and compared to conventional resin based sorbents and nanoporous silica materials with similar surface chemistries.