@article {Layek:2013:1533-4880:1834,
title = "M{\"o}ssbauer and Magnetic Studies of Surfactant Mediated CaMg Doped Ferrihydrite Nanoparticles",
journal = "Journal of Nanoscience and Nanotechnology",
parent_itemid = "infobike://asp/jnn",
publishercode ="asp",
year = "2013",
volume = "13",
number = "3",
publication date ="2013-03-01T00:00:00",
pages = "1834-1840",
itemtype = "ARTICLE",
issn = "1533-4880",
eissn = "1533-4899",
url = "https://www.ingentaconnect.com/content/asp/jnn/2013/00000013/00000003/art00036",
doi = "doi:10.1166/jnn.2013.7109",
author = "Layek, Samar and Mohapatra, M. and Anand, S. and Verma, H. C.",
abstract = "Ultrafine (25 nm) particles of amorphous CaMg co-doped ferrihydrite have been synthesized by surfactant mediated co-precipitation method. The evolution of the amorphous ferrihydrite by CaMg co-doping is quite different from our earlier investigations on individual
doping of Ca and Mg. Amorphous phase of ferrihydrite for the present study has been confirmed by X-ray diffraction (XRD) and M{\"o}ssbauer spectroscopy at room temperature and low temperatures (40 K and 20 K). Hematite nanoparticles with crystallite size about 8, 38 and 70 nm were obtained
after annealing the asprepared samples at 400, 600 and 800 \textdegreeC respectively in air atmosphere. Superparamagnetism has been found in 8 nm sized hematite nanoparticles which has been confirmed from the magnetic hysteresis loop with zero remanent magnetization and coercive field and also from
the superparamagnetic doublet of its room temperature M{\"o}ssbauer spectrum. The magnetic properties of the 38 and 70 nm sized particles have been studied by room temperature magnetic hysteresis loop measurements and M{\"o}ssbauer spectroscopy. The coercive field in these hematite nanoparticles
increases with increasing particle size. Small amount of spinel MgFe2O4 phase has been detected in the 800 \textdegreeC annealed sample.",
}