Biju Thangjam; Ibetombi Soibam
Abstract
Ni-Cu-Zn ferrites with compositional formula Ni0.8-xCuxZn0.2Fe2O4, where 0.0≤x≤0.5 in steps of 0.1 were synthesized by the citrate precursor method. The samples were subjected to final sintering at 900ᵒC for 2h after a pre-sintering at 600ᵒC for 4h. X-ray diffraction patterns confirmed the ...
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Ni-Cu-Zn ferrites with compositional formula Ni0.8-xCuxZn0.2Fe2O4, where 0.0≤x≤0.5 in steps of 0.1 were synthesized by the citrate precursor method. The samples were subjected to final sintering at 900ᵒC for 2h after a pre-sintering at 600ᵒC for 4h. X-ray diffraction patterns confirmed the formation of single phase spinel structure. The average crystallite size was calculated using Scherrer’s formula and was found to vary from 33nm to 39nm, clearly indicating the formation of nanoparticles. The infrared spectra were recorded at room temperature for all the samples in the range of 450 cm‾1 to 4000 cm‾1 using Perkin Elmer FT-IR Spectrometer. Jahn-Teller effect emerges which can be identified through the FT-IR Spectroscopy of the samples. This phenomenon may result in useful electro and magneto- optical applications. Possible mechanism is being discussed. Copyright © 2017 VBRI Press.
Elangbam C. Devi; Ibetombi Soibam
Abstract
Manganese ferrite nanoparticles with chemical formula MnFe2O4 have been synthesized by low temperature chemical co-precipitation method. The structural and optical properties of the nanoparticles were studied by using X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray ...
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Manganese ferrite nanoparticles with chemical formula MnFe2O4 have been synthesized by low temperature chemical co-precipitation method. The structural and optical properties of the nanoparticles were studied by using X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), fourier transform infra-red spectroscopy (FTIR) and UV-visible absorption spectroscopy. XRD confirm pure spinel phase formation of the prepared sample. All the observed peaks correspond to the standard diffraction pattern of manganese ferrite having JCPDS card number 74-2403. From the XRD data, the average crystallite size was calculated and found to be 27.40 nm. The FTIR spectrum shows the characteristic bands of the spinel ferrite. Morphology of the nanoferrites was given by SEM image revealing that the particles are approximately spherical in shape. The elemental composition along with their relative ratios was given by EDAX and was found to be in agreement with their initial calculated values. UV- visible absorption spectrum of the prepared sample shows characteristic absorption in visible range and from the UV-visible absorption data the band gap of the prepared sample was determined. MnFe2O4 nanoparticles were found to possess a narrow band gap of 1.4 eV which may find applications in photocatalytic degradation of pollutants. The simple co-precipitation method proves to be an effective method for synthesis of pure phase manganese ferrite nanoparticles. Copyright © 2017 VBRI Press.
Sanatombi Sorokhaibam; Ibetombi Soibam; Sumitra Phanjoubam
Abstract
Substituted lithium ferrite having the chemical formula Li0.35 Ni0.1 Mn0.1 Zn0.2 Fe2.35 O4 have been synthesized by the citrate precursor method. The sample was given pre-sintering at 650oC in a conventional furnace. Final sintering was carried out at 900oC in a conventional surface and another ...
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Substituted lithium ferrite having the chemical formula Li0.35 Ni0.1 Mn0.1 Zn0.2 Fe2.35 O4 have been synthesized by the citrate precursor method. The sample was given pre-sintering at 650oC in a conventional furnace. Final sintering was carried out at 900oC in a conventional surface and another in a microwave furnace. The spinel phase structure of the conventional (CS) and microwave sintered (MS) samples was confirmed by the XRD patterns. From the analysis of XRD data, the crystallite size of the samples was estimated and smaller crystallite size was observed in the microwave sintered sample. Scanning Electron Microscopy (SEM) was also carried out. The dielectric studies were investigated. Room temperature dielectric constant ( ) and dielectric loss (tan d) were studied as a function of frequency. Experimental results show dispersion for variation of dielectric constant and dielectric loss tangent with frequency for both CS and MS sample. However, microwave sintered sample show lower dielectric constant and losses. Possible mechanism is being discussed. Copyright © 2016 VBRI Press.