A comparative study of structural, electrical and magnetic properties of magnesium ferrite nanoparticles synthesised by sol-gel and co-precipitation techniques

Nano-sized magnesium ferrite was synthesised using co-precipitation and sol-gel techniques. Structural characterisation was performed using X-ray diffractometer (XRD), Fourier transform infrared (FTIR) spectrometer and scanning electron microscope. XRD analysis reveals the prepared samples are single phasic without any impurity. Particle size calculation shows that the crystallite size of sol-gel prepared samples is 9 nm and co-precipitation sample is 11 nm. FTIR analysis confirmed spinel structure of the prepared samples. Magnetic measurements show that both the samples are ferromagnetic with a high degree of isotropy in co-precipitation derived sample. The frequency dependence of the dielectric constant in the range 100 Hz–20 MHz was also investigated in the temperature range 303–533 K. The results of both the samples followed Maxwell–Wagner model based on interfacial polarisation in consonance with Koops theory.