Uniform hematite (α-Fe 2 O 3 ) nanoparticles have been successfully synthesized through a simple one-step low temperature reflux condensing method which requires no surfactants or templates. The crystallite size was calculated by using Debye-Sherrer formula, and it showed the range of 4-27 nm. The lattice parameters of the samples were measured by Rietveld analysis. The morphology of the products was studied by high resolution scanning electron microscopy (HR-SEM), and it was confirmed by high resolution transmission electron microscopy (HR-TEM). The HRTEM images exhibit the well defined lattice fringes of α-Fe 2 O 3 particles that confirm their high crystallinity. The formation of pure α-Fe 2 O 3 was further confirmed by using energy dispersive X-ray (EDX) analysis. The optical properties and the bandgap energy were measured by UV-Visible diffuse reflectance spectra (DRS) and photoluminescence (PL) spectra. The bandgap energy was measured by using Kubelka-Munk method, and the value was found to be 2.26 eV. Magnetic hysteresis (M-H) loops revealed that the as-prepared α-Fe 2 O 3 samples displayed ferromagnetic behavior. These results show that the prepared hematite possess good magnetic properties. © 2014 Springer Science+Business Media New York.

John Kennedy L

Physics

School of Advanced Sciences

Chennai Campus

Adinaveen T

Judith Vijaya J

Vellore Institute of Technology (VIT) is a private university located in&nbsp;Tamil Nadu, India. Founded in 1984, as Vellore Engineering College, the institution offers 20 undergraduate, 34 postgraduate, four integrated and four research programs. It has campuses in Vellore, Amravati, Bhopal and Chennai.

VIT is one of the top ranked private universities in India according to NIRF, THE and QS Rankings.&nbsp;Govt. of India has recognized&nbsp;VIT, Vellore as an&nbsp;Institution of Eminence. This has allowed VIT to take independent quality initiatives and move up in world ranking.

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VIT University

Journal of Superconductivity and Novel Magnetism

Nano-sized copper doped zinc ferrite powders, Zn1-xCu xFe2O4 (x = 0.0, 0.1, 0.2, 0.3, 0.4 and 0.5) were synthesized by microwave combustion method. The structural, morphological and magnetic properties of the products were determined and characterized in detail by X-ray diffraction (XRD), high resolution scanning electron microscopy (HR-SEM), energy dispersive X-ray spectroscopy (EDX) and vibrating sample magnetometer (VSM). X-ray analysis showed that all compositions crystallize with a cubic spinel-type structure. The lattice parameter decreased from 8.443 to 8.413 Å with increasing Cu content. The average crystallite size was found in the range of 41.20-45.84 nm. Magnetic measurements revealed that for lower Cu concentration (x ≤ 0.2), the system shows a superparamagnetic behavior whereas for higher concentration (x ≥ 0.2), it becomes ferromagnetic. It has been explained in terms of random distribution of Zn2+ and Fe 3+ ions at tetrahedral [A] and octahedral [B] sites. The saturation magnetization (Ms) varies considerably with Cu content to reach a maximum value for Cu0.5Zn0.5Fe2O4 composition, i.e. 58.58 emu/g. The high saturation magnetization of these samples suggests that this method is suitable for preparing high quality nanoparticles for magnetic applications. The broadband visible emission is observed in the entire photoluminescence (PL) spectrum and the estimated energy band gap is about 2.1 eV. The composition with x = 0.5 showed the highest intensity and was explained on the basis of disordered cluster model. © 2012 Elsevier B.V. All rights reserved.

Journal of Molecular Structure

Structural, optical and magnetic properties of Zn1−xCuxFe2O4 nanoparticles prepared by microwave combustion method

Pure and strontium doped zinc ferrite (Zn1-xSr xFe2O4) nanoparticles were prepared by the microwave combustion method using urea as the fuel. Rietveld refinements of X-ray diffraction pattern confirm the formation of single cubic spinel phase with an average crystallite size in the range of 25-42 nm. The broad visible emission band is observed in the entire photoluminescence spectrum. The estimated band gap energy is found to decrease with increasing Sr content, i.e. 2.1-1.72 eV. Magnetic measurements at room temperature revealed that at lower Sr concentration (x≤0.2), the system shows a superparamagnetic behavior, whereas at higher Sr concentration (x≥0.2), it becomes ferromagnetic. The relatively high saturation magnetization of the as-prepared Sr-doped ZnFe 2O4 nanoparticles suggest that this method is suitable for preparing high-quality nanocrystalline magnetic ferrites for practical applications. The mechanism for the formation of ZnFe2O4 by the microwave combustion method is also discussed in the present study. Microwave combustion produced sufficient energy for the formation of ZnFe 2O4, because of its homogeneous distribution within the raw materials. This results in the formation of nanoparticles and early phase formation within few minutes of time. © 2013 Elsevier Ltd and Techna Group S.r.l.

Ceramics International

Microwave combustion synthesis, structural, optical and magnetic properties of Zn1−xSrxFe2O4 nanoparticles

Materials Letters

Preparation and characterization of dye sensitized solar cell based on nanostructured Fe2O3

Synthesis, optical and magnetic properties of α-Fe2O3 nanoparticles with various shapes

Journal of Alloys and Compounds

Rapid synthesis and optical properties of hematite (α-Fe2O3) nanostructures using a simple thermal decomposition method

Studies on the Structural, Morphological, Optical, and Magnetic Properties of α-Fe2O3 Nanostructures by a Simple One-Step Low Temperature Reflux Condensing Method

Journal	Data powered by TypesetJournal of Superconductivity and Novel Magnetism
Publisher	Data powered by TypesetSpringer Science and Business Media LLC
ISSN	1557-1939
Open Access	No