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Mater Sci Nanotechnol 2017
Volume 1 Issue 3 Magnetic Materials 2017
Page 87
October 09-10, 2017 London, UK
International Conference on
Preparation of painting material of Li-Ni ferrite
Emad K Al-Shakarchi
Nahrain University, Iraq
The Li-Ni Nano ferrite samples with the structure Li0.5-
0.5xNixFe2.5-0.5xO4 was prepared by hydrothermal method.
They prepared two sets, from metal chlorides, and ferrous
sulfate with NaOH. In each set, the variation of (x) was 0,
0.1, 0.3, to 1.0. The samples were without and with adding
Fe+2. The ratio of Fe+3/Fe+2 was kept at 1.7. The preparation
temperature was 1550C and pH-value was equal to 11. The
samples showed spinel ferrite structure beyond x=0.3 for set
one and pure phase in 0.3 by using Fe+2. Lattice constant of set
two was a little lower than set one and both were little lower
than theoretical. The crystallite size gets minimum at x=0.5
for set one and roughly maximum at x=0 for set two. FTIR
spectrums tetrahedral showed peak shift to higher frequency
with increasing Ni+2 concentration. Particles shapes were:
rods (often hematite) average diameter 40 nm, spherical
(nanocube ferrite in origin) sizing around 20 nm. M-H Loops
had S-shape like to superparamagnetic one. Generally, the
prepared samples have lower coercivety, higher saturation
magnetization. Both sets gave maximum susceptibility at
x=0.5. These results explained based on composition, cations
distribution, cation interactions and particle size. Resonance
microwave absorption by using FMR test showed that the
maximum imaginary susceptibility χ" is at x=0.5 for set one
besides high values of 0.7 and 0.9, with largest line width of
about 950 G at x=0.7. Set two showed maximum absorption
(χ") and line width at x=0.9. The powder mixed with Novalac
epoxy by 7.93% wt. The FMR test with no field showed that
high absorption to microwave field for frequencies larger
than 19 GHz. The explanation of that set two samples has
larger absorption than the set one that based on hopping
conductivity and magnetic parameters (Ms and Hc) variation.
Transmission line method by using VNA in X-band and Ku-
band showed that return (reflection) RL loss got minimum at
x=0.3 in for set one in X-band whereas that happen at x=0.3
and x=0.5 for set two. Adding Fe+2 lowered the minimum by
a factor of more than 1.5. The insertion losses IL in X-band
ranging from -4.5 to -7 dB, RL and IL in Ku-band have same
behavior but their values were lower. RL got minimum at
x=0.5 with value of about near to -18dB whereas it was
around -12dB by adding Fe+2, the average IL in Ku-band was
about -6dB.
Materials Science and Nanotechnology