Mössbauer study of intermediate superparamagnetic relaxation of maghemite (γ-Fe 2 O 3 ) nanoparticles

Structural and Magnetic Properties of Monophasic Maghemite (<i>γ</i>-Fe<sub>2</sub>O<sub>3</sub>) Nanocrystalline Powder

“…This method is chosen because of the lower temperatures required to the synthesis compared to other techniques such as hydrothermal technique [14] which require interval of temperature from 130˚C to 250˚C and high vapor pressure (from 0.3 to 4 MPa). On the other hand, in our previous report [15], we studied the intermediate super paramagnetic relaxation effect of γ-Fe 2 O 3 nanoparticles by Mössbauer spectroscopy at different temperatures. The relaxation process was broken by decreasing the temperature up to 4.2 K proving the single-phase formation of the MNCs fitting the spectrum with the corresponding two typical hyperfine fields of maghemite.…”

Synthesis, Characterization, and Toxicity Evaluation of Dextran-Coated Iron Oxide Nanoparticles

“…Iron oxide nanoparticles at a nanometric scale have been intensively studied due to their superparamagnetic properties and also because of their lack of toxicity at low concentrations of different types of cells [15][16][17].…”

Synthesis and characterization of hybrid materials containing iron oxide for removal of sulfides from water

“…Reducing the nanoparticle size usually results in a collapse of the magnetic six-line structure to a paramagnetic quadrupole doublet, which is not the consequence of thermodynamic transition but occurs when the superparamagnetic relaxation time of the nanoparticles becomes comparable with the time scale of Mössbauer spectroscopy [21,21]. The spread in particle sizes results in spread of relaxation times and substantially broadened spectra.…”