In general, ilmenite FeTiO 3 is synthesized by solid-state reaction at very high pressure and high temperature. Synthesis of FeTiO 3 is not an easy task as the Fe 2 þ ions are not stable. Therefore, it is really challenging to prepare this material. In this work nano-ilmenite FeTiO 3 was synthesized by the sol-gel method. Structural, optical and magnetic characterizations were performed. The bandgap of FeTiO 3 was determined to be 2.8 eV showing FeTiO 3 as suitable wide bandgap material for technological applications. The FeTiO 3 nanoparticles exhibit weak ferromagnetic properties at and below room temperature. The Né el temperature was observed to be around 52 K.

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Thin films of rare earth (RE)-doped BiFeO3 (where RE=Sm, Ho, Pr and Nd) were grown on LaAlO3 substrates by using the pulsed laser deposition technique. All the films show a single phase of rhombohedral structure with space group R3c. The saturated magnetization in the Ho- and Sm-doped films is much larger than the values reported in the literature, and is observed at quite a low field of 0.2 T. For Ho and Sm doping, the magnetization increases as the film becomes thinner, suggesting that the observed magnetism is mostly due to a surface effect. In the case of Nd doping, even though the thin film has a large magnetic moment, the mechanism seems to be different.

A series of polycrystalline spinel ferrites with composition, CoFe 2-x Al x O 4 (0 ≤ x ≤ 1), have been synthesized by sol-gel method. The effect of Al-substitution on structural and dielectric properties is reported in this paper. X-ray diffraction analysis revealed the nanocrystalline nature in the prepared ferrite samples. The particle size, D, decreases with increase in Al-content. The lattice parameter, a and X-ray density, d x , decreased with increase in Al-content. The dielectric properties for all the samples have been studied as a function of frequency in the range 100 Hz-10 MHz. Dielectric properties such as dielectric constant, ε′, dielectric loss, ε″ and dielectric loss tangent, tan δ, have been studied for nanocrystalline ferrite samples as a function of frequency. The dielectric constant and dielectric loss obtained for the nanocrystalline ferrites proposed by this technique possess lower value than that of the ferrites prepared by other methods for the same composition. The low dielectric behaviour makes ferrite materials useful in high frequency applications.

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