Powdery nickel ferrite, NiFe2O4 has been obtained by soft mechanochemical synthesis in a planetary ball mill. Ni(OH)2 and Fe(OH)3 are used as initial compounds. This mixture was mechanically activated for 25h, uniaxial pressed and sintered at 1100?C for 2h. The phase composition of the sintered sample was analyzed by X-ray diffraction (XRD), energy dispersive spectrometer (EDS) and Raman spectroscopy. Morphologies were examined by scanning electron microscopy (SEM). The electrical DC/resistivity/conductivity at different temperatures was measured using a Source Meter Keithley 2410. An Impedance/Gain-Phase Analyzer (HP-4194) was used to measure the impedance spectra (100Hz - 10MHz) at different temperatures.

Single phase cobalt ferrite (CoFe2O4) with nanoparticles of similar sizes (15.7-19 nm) was obtained by different synthesis methods: coprecipitation, ultrasonically assisted coprecipitation, coprecipitation followed by mechanochemical treatment, microemulsion and microwave assisted hydrothermal synthesis. The obtained CoFe2O4 samples have been studied using a variety of characterization techniques: X-ray diffraction (XRD), Raman spectroscopy, far infrared (FIR) reflectivity and attenuated total reflectance (ATR) in combination with Fourier-transform infrared (FTIR) spectroscopy in mid IR spectra. Different methods of synthesis produced nanoparticles with different lattice constants, internal stresses and different cation inversion values. This is confirmed in the subtle changes in the Raman and IR spectra of different CoFe2O4 nano-powders. The Raman spectra of CoFe2O4 were compared with the spectra of other ferrites and some cubic oxide spinels in an attempt to evaluate the contribution of tetrahedral and octahedral oscillations in certain Raman modes.

Barium bismuth tantalate-BaBiTa₂O₉ has been prepared by conventional method based on solid-state reaction using BaCO₃, Bi₂O₃ and Ta₂O₅ as starting materials. It was added excess of 10 mol% of bismuth aiming to improve the dielectric and ferroelectric properties. The calcinated powders and sintered pellets were analyzed by XRD and SEM. BaBiTa₂O₉ ceramics with high density was obtained at sintering temperature of 1050°C for 2 h. The faced grains with a rod-like morphology were observed for BaBiTa₂O₉ with 10 mol% excess bismuth. The dielectric constant measured at frequency of 100 kHz at room temperature was 389 with dielectric loss of 0.032. BBT ceramic prepared with excess of 10 mol% bismuth possesses ferroelectric properties with remnant polarization of P _r ≈ 15 μC cm⁻² and coercive field of E _c ≈ 58 kV cm⁻¹. The hysteresis loop is very well performed with the shape characteristic of ferroelectric materials.

Bismuth titanate, Bi4Ti3O12 (BIT) nanosized powders have been successfully synthesized via high energy mechanochemical activation. The phase formation of BIT, crystal structure, microstructure, crystallite size and specific surface area were followed by XRD, scanning electron microscopy (SEM) and the BET specific surface area measurements. The BIT milled 2 h shows the orthorhombic crystalline structure with small amount of amorphous phase. The microstructure of Bi4Ti3O12 ceramics sintered at 1000?C for 12h exhibit plate-like grain structure.