Role of rare-earth (Nd3+) ions on structural, dielectric, magnetic and Mossbauer properties of nano-sized CoFe2O4: useful for high frequency application

The glycine nitrate technique is used to synthesis a series of Neodymium substituted Cobalt Ferrite samples i.e. Co1-xNdxFe2O4 (x = 0, 0.1, 0.3, 0.5, 0.7). XRD, FT-IR, TEM, VSM and Mössbauer spectrum was carried out to investigate the structural, morphological and magnetic properties. Crystallite sizes calculated from the XRD patterns exhibited a decreasing trend with the increase in Nd content and was in good agreement with FESEM results. Temperature-dependent dielectric properties: dielectric constant (ε′), dielectric loss (ε″) and resistivity and activation energy were studied as a function of applied frequency in the range from 100 Hz to 1 MHz. The conductivity measurements divulge the semiconducting characteristic of the synthesised sample. The dielectric study indicated the dielectric dispersion curve to have possessed typical dielectric dispersion which can be explained on the basis of Koop’s theory based on the Maxwell–Wagner model. Incorporation of Nd in Cobalt nanoferrite significantly enhances the dielectric properties providing a gateway to high frequency device based application. The magnetic properties reveal a strong dependence on the grain size where the saturation magnetization reduced with the average particle size.