Principal Investigator
: Prof. R.M.Patil
Asso.Prof. in Physics
Dept. of Physics
B.K.College,Chikodi
Title of Project
: PREPARATION,CHARACTERIZATION
AND PROPERTIES OF COPPER
SUBSTITUTED LITHIUM – CADMIUM
FERRITES
The Executive Summary of MRP
Ferrites have very vast applications from microwaves to radio frequencies. Due to its
very low conductivity it has many microwave applications. Ferrites find wide
application on various fields due to its high efficiency, low cost and small volume.
Ferrites materials are used to design inductors, antenna cores in radio receivers,
flyback transformer core for television picture tubes, modern digital computers and
transformations.
The spinel ferrites are hence extensively used for miniaturization The spinel structure
is physically flexible, leading to a wide range of physical properties and hence
practical applications. ferrites are a class of the ceramic materials which exhibit
magnetic properties.In general the ferrites have variety applications.
However , there is a dearth of information in the literature, regarding the researches
on the impact of copper substitution on the properties Li-Cd ferrites. Therefore our
present research work is proposed to be focused on the following objectives.
1. Synthesis of Li-Cu-Cd ferrites with the stoichiometric formula, LixCu 0.72xCd0.3 Fe2+xO4 (x = 0.05, 0.1, 0.15, 0.20 and 0.25) by standard ceramic
technique.
2. Confirmation of the phase formation and to undertake the crystallographic
studies by XRD.
3. To detect the IR absorption fundamental bands for cross verification of the
material phase formation and computation of force constants.
4. To obtain surface morphological-microstractual details by SEM.
In the present case ceramic method was used to prepare the ferrites with the general
formula LixCu0.7-2xCd0.3Fe2+xO4 (x = 0.05, 0.1, 0.15, 0.20 and 0.25. High purity
oxides of lithium, copper , cadmium and iron were weighed accurately by using
microbalance in the required molar proportions and mixed mechanically in agate
mortar in acetone medium. All samples were pre-sintered at 800oC for 8 hours.
The pre-sintered powders were subjected to hard milling process in acetone medium
and dried powders were sieved to eliminate the large sized particles. The powder
samples were subjected to X-ray diffraction, IR absorption and Scanning Electron
microscopic examinations for characterization.
X-Ray diffraction of the sample were obtained from Sophisticated Test &
Instrumentation Centre (STIC), Cochin University of Science and Technology,
Cochin - 682 022, Kerala. The powder samples were subjected to X-ray diffraction
using CuKα-radiation(λ=1.5406Ao) on a PHILIPS PW3710 diffractometer. The range
of 2θ is taken to be from 20o to 80o. The diffractograms were indexed in the light of
the crystal structure of natural spinel , MgAl2 O4 . The prominent line in the
diffraction pattern of spinels corresponds to (311) plane. The value of angle
corresponding to (311) plane is noted from the diffraction pattern . Substituting the
values of sinθ, (hkl) and λ in the above equation, the lattice parameter a, the indices
and d-values for other planes were calculated by usual procedure.
The phase purity of the different compositions was analyzed using powder X-ray
diffraction. The X-ray diffraction patterns of the samples in the present system
LixCu0.7-2xCd0.3 Fe2+xO4 (x = 0.05, 0.1, 0.15, 0.20 and 0.25).
I.R. of the sample were obtained from Sophisticated Test & Instrumentation
Centre (STIC), Cochin University of Science and Technology, Cochin - 682 022,
Kerala.The IR-spectrographs for LixCu0.7-2xCd0.3 Fe2+xO4 in KBr medium were
recorded within the range of wave numbers from 4000 to 400 cm-1 by a Perkin ElmerSpectrum 2000 FTIR spectrophotometer .
The absorption bands are summarized in Table 3. As an essential feature of spinel
ferrites, all the above samples exhibit two absorption bands at the wave numbers
ν1and ν2 between 600cm-1 and 400cm-1 respectively. The primary band υ1 is observed
at around 450cm-1in case of all the samples. The second absorption band υ2 are in the
ranges of 585–573cm−1. It is observed that,the absorption band edges ν2 was found to
shift towards higher frequencies with the increase in composition x. This is attributed
to the vibrations of ‘Fe3+-O2-’bonding on octahedral(B)-site. The vibrations of ‘Fe3+O2-’bonding on tetrahedral(A)-site leads to a shift in band edge ν1. The other two
bands edges ν3 and ν4 are associated with vibrations of metal ions in isotropic force of
their octahedral and tetrahedral environments.
SEM of the sample were obtained from Dept of Physics, Shivaji University ,
Kolhapur. Scanning electron microscope (SEM- JEOL JSM-5600 LV) was employed
for recording the micrographs of the ferrites of different compositions . The scan is
performed at high vacuum mode using accelerating voltage 30 kV, working distance
20mm, and magnification ×1000.
The SEM micrographs with magnification ×1000 recorded on a Scanning Electron
Microscope for the LixCu0.7-2xCd0.3Fe2+xO4 ferrite samples. The micrographs reveal
that, the ferrite sample with x=0.05 has higher average grain size with almost
spherical shape. The grain size appears to be decreasing with the increase in
composition x till x=0.20. However, for the composition x=0.25 presence of
cylindrical and rectangular micro-rods is found. Porosity seems to be decreasing from
x=0.05 to 0.20, but it is higher for x=0.025 sample
.
Principal Investigator