P. Neelima; S. R. Murthy
Abstract
Microwave-hydrothermal (M-H) method had been employed to synthesize a series of Dy3+doped Mn-Zn ferrite Mn0.6Zn0.4Fe2–xDyxO4 (x=0, 0.01, 0.03, 0.05, 0.07, 0.09) nanopowders at 160°C/30 min. The prepared samples have been characterized by Fourier Transform Infrared Spectrometer. The grain size ...
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Microwave-hydrothermal (M-H) method had been employed to synthesize a series of Dy3+doped Mn-Zn ferrite Mn0.6Zn0.4Fe2–xDyxO4 (x=0, 0.01, 0.03, 0.05, 0.07, 0.09) nanopowders at 160°C/30 min. The prepared samples have been characterized by Fourier Transform Infrared Spectrometer. The grain size of sintered ferrites are in the range of 60-70 nm. Decrease in saturation magnetization and increase in coercivity were observed with an increase of Dy3+ concentration in Mn-Zn ferrites. The complex permeability and complex permittivity of the prepared samples were measured in the frequency range of 2–18 GHz using a using a vector network analyzer. It is observed that small variation of Dy3+ substitution in spinel ferrite tailored microwave absorbing parameters dramatically. The reflection loss (RL) increased with the Dy3+ content upto x ≤ 0.03. The sample with x=0.03 of thickness 2.3 mm showed minimum reflection loss of -20.5 dB with a bandwidth of 3.8 GHz. Thus the present materials exhibit good microwave absorption properties and hence can act as EMI suppressors. Copyright © 2018 VBRI Press.
M. Kanakadurga; S. R. Murthy; Arya Das; Rakesh K. Sahoo; Saroj K. Singh
Abstract
ZnO nano-platelets have been prepared using a high pressure reactor via hydrothermal route. The as-formed fine platelets morphology of the as-synthesized powder was confirmed from the scanning electron microscopy (SEM) images. The elemental analysis using energy dispersive X-ray (EDAX) analysis indicated ...
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ZnO nano-platelets have been prepared using a high pressure reactor via hydrothermal route. The as-formed fine platelets morphology of the as-synthesized powder was confirmed from the scanning electron microscopy (SEM) images. The elemental analysis using energy dispersive X-ray (EDAX) analysis indicated the presence of Zn, O, Na and Cl which confirms the presence of ZnO as major and NaCl as the minor phase. The precipitation of this minor phase after growth and catalytic induction in nano-platelet (NP) morphology during growth has been elucidated. The electrochemical performance of this as-synthesized powder is quite promising. Additionally, the effect of this minor NaCl phase in changing the ionic equilibrium of the electrolyte in capacitance measurement has been analyzed.
