Influence of Mg concentration on physico-chemical properties of Cd ferrites (CdMg1.5xFe2−xO4) synthesized by sol–gel combustion method

• Highly crystalline, single phase ferrites are obtained.
• Saturation magnetization increases with increase in Mg2+ doping up to x = 0.7.
• Nanosized particles tend to form inverted spinel structure.
• Ferrites obtained have large surface area.

The nanofabrication, characterization, microstructural and magnetic properties of pure and Mg2+ doped cadmium ferrite (CdFe2−xMg1.5xO4; x = 0.0–0.7) have been carried out. Morphology and the microstructure of the nanostructured oxide materials obtained through sol–gel process using hydrated metal-citrate precursor were studied by powder X-ray diffraction (XRD), electron microscopy (SEM, TEM) and N2-physisorption (BET) showing an ordered cubic arrangement of 11–23 nm diameter pores with single-phase spinel grains averaging 13–38 nm in diameter. Room temperature magnetic measurements using magnetometer (VSM) demonstrate that the nature and concentration of dopant both control the site preference in the crystal lattices, suggesting the partial inverted spinel structure of soft Cd ferrites, which differs from bulk CdFe2O4 showing practically no inversion in structure. An increase in Mg2+ substitution leads to a decrease in the lattice parameter, an increase in saturation magnetization as well as BET surface area of the as-synthesized ferrites.