%0 Journal Article
%T Structural and Magnetic Properties of Monophasic Maghemite (<i>¦Ã</i>-Fe<sub>2</sub>O<sub>3</sub>) Nanocrystalline Powder
%A Juan Adri¨¢n Ramos Guivar
%A Arturo Isa¨ªas Mart¨ªnez
%A Ana Osorio Anaya
%A Luis De Los Santos Valladares
%A Lizbet Le¨®n F¨¦lix
%A Angel Bustamante Dominguez
%J Advances in Nanoparticles
%P 114-121
%@ 2169-0529
%D 2014
%I Scientific Research Publishing
%R 10.4236/anp.2014.33016
%X <div style=\"text-align:justify;\">
	<span style=\"font-family:'';\"><span style=\"font-family:Verdana;\">Structural and magnetic
studies of monophasic maghemite (</span><i><span style=\"font-family:Verdana;\">¦Ã</span></i><span style=\"font-family:Verdana;\">-Fe</span><sub><span style=\"font-family:Verdana;\">2</span></sub><span style=\"font-family:Verdana;\">O</span><sub><span style=\"font-family:Verdana;\">3</span></sub><span style=\"font-family:Verdana;\">)
magnetic nanocrystallites (MNCs) synthesized by the co-precipitation chemical
route are reported in this paper. For the synthesis, a starting precursor of
magnetite (Fe</span><sub><span style=\"font-family:Verdana;\">3</span></sub><span style=\"font-family:Verdana;\">O</span><sub><span style=\"font-family:Verdana;\">4</span></sub><span style=\"font-family:Verdana;\">)
in basic medium was oxidized at room temperature by adjusting the pH = 3.5
at 80¡ãC in an acidic medium without surfactants. X-ray diffraction (XRD)
pattern shows widened peaks indicating nanometric size and Rietveld Refinement confirms
only one single-phase assigned to </span><i><span style=\"font-family:Verdana;\">¦Ã</span></i><span style=\"font-family:Verdana;\">-Fe</span><sub><span style=\"font-family:Verdana;\">2</span></sub><span style=\"font-family:Verdana;\">O</span><sub><span style=\"font-family:Verdana;\">3</span></sub><span style=\"font-family:Verdana;\"> MNCs. High Resolution Transmission Electron Microscopy (HR-TEM) demonstrates
the formation of nanoparticles with diameter around </span><i><span style=\"font-family:Verdana;\">D</span></i><span style=\"font-family:Verdana;\"> ¡Ö 6.8 ¡À 0.1 nm which is in good agreement with Rietveld Refinement
(6.4 ¡À 1 nm). A selected area electron diffraction pattern was carried out to
complement the study of the crystalline structure of the </span><i><span style=\"font-family:Verdana;\">¦Ã</span></i><span style=\"font-family:Verdana;\">-Fe</span><sub><span style=\"font-family:Verdana;\">2</span></sub><span style=\"font-family:Verdana;\">O</span><sub><span style=\"font-family:Verdana;\">3</span></sub><span style=\"font-family:Verdana;\"> MNCs. </span><i><span style=\"font-family:Verdana;\">M</span></i><span style=\"font-family:Verdana;\">(</span><i><span style=\"font-family:Verdana;\">H</span></i><span style=\"font-family:Verdana;\">) measurements taken
at different temperatures show almost zero coercivity and remanence indicating
superparamagnetic domain and high magnetic saturation.</span></span><span style=\"line-height:1.5;font-family:Verdana;\"></span> 
</div>
%K Monophasic Nanomaghemite
%K Rietveld Refinement
%K TEM
%K SAED
%K &lt
%K i&gt
%K M-H&lt
%K /i&gt
%K Loops
%K ZFC
%U http://www.scirp.org/journal/PaperInformation.aspx?PaperID=49326