Abstract
Lithium nickel ferrite Li0.5Ni0.5Fe2O4 was synthesized by the sol-gel auto combustion method. The prepared ferrite was mixed with polystyrene with ratio 0.25:1(FP1), 0.50:1(FP2), 0.75:1(FP3) and 1:1(FP4) to get ferrite-polystyrene composite. The synthesized samples were characterized by x-ray diffraction, dielectric and direct current resistivity measurements. The x-ray diffraction pattern shows that the polystyrene is amorphous in nature. The diffraction peaks of ferrite-polystyrene composite become sharper and narrower by increasing the ferrite filler contents. Room temperature resistivity of the composites decreased significantly from 4.63 x 10(13) Omega-cm to 3.67 x 10(9) Omega-cm with increasing ferrite content and temperature dependent resistivity decreased with increasing temperature. The dielectric constant increased as the concentration of ferrite was increased in the base sample. A maximum value of 23.60 was achieved for the last sample. Conversely, the increase in frequency results from the decrease in dielectric constant followed the Maxwell-Wagner model.