Structural and Magnetic Properties of Copper-Substituted Nickel–Zinc Nanoparticles Prepared by Sol-Gel Method

Soft ferrite materials of high magnetic permeability and lower losses, essential to multilayer chip inductor applications, require stringent processing conditions to enable the materials with the desired characteristics. Copper-substituted Ni–Zn nanoferrite was processed through the sol-gel technique using polyvinyl alcohol as a chelating agent to control the particle size. The structural parameters and magnetic properties were examined by X-ray diffraction, field emission scanning electron microscopy (FESEM), Fourier-transform infrared spectroscopy and vibrating-sample magnetometer techniques respectively. FESEM images showed the formation of anisotropic structures like nanorods, nanoflower bouquet and nanofibres with copper substitution. The occupancy of copper ions towards octahedral sites has been ascertained by DC resistivity measurements, whereas the magnetic properties have been discussed based on cation distribution. The observed high values of magnetic permeability and DC resistivity suggest that the Ni–Zn ferrite system yields useful electromagnetic properties for smaller concentrations of copper substitution.