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In this work, the ZnO-TiO2 mixed phase nanoparticles were prepared by solid state reaction method by using ZnO and TiO2 powder as precursors. The X-ray diffraction pattern shows a dominant phase of Zinc Orthotitanate (Zn2TiO4). The average particle size (58±18 nm) calculated by the analysing FESEM data closely matches with the particle size calculated by Scherrer’s equation. The calculated average particle size is significantly smaller than the previously published results of nanoparticles, prepared by same method. In the Brunauer-Emmett-Teller (BET) study the specific surface area of the nanoparticles was found as 8.78 m2/g which is similar to the surface area reported in this material prepared by mechanochemical method. The method which we report is simpler and cost effective unlike the previous reported.

The nanocrystalline Pb(sub 0.92)Nd(sub 0.08)(Zr(sub 0.53)Ti(sub 0.47))(sub 0.98)O(sub 3)(PNZT) is synthesized by high-energy ball milling (mechanical alloying). The analysis of impedance and dielectric properties of PNZT as a function of temperature has showed the high permittivity of 10626 at 10 kHz at the Curie temperature (Tc), broadening of permittivity peak, lowering of Tc, decrease in conductivity and increase in relaxation time with the decrease in crystalline size.

The nanocrystalline Gd-doped lead titanium zirconate (PGZT) with a high dielectric constant was synthesized by a combination of ball milling and sintering. The dielectric parameters of PGZT are decided significantly by the crystallite size according to the results obtained.

We present in this article, the latest development in electrical properties of lithium titanate (Li2TiO3) with different sintering (800°C, 900°C and 1000°C), which were prepared by high-energy ball milling technique. The transformation of β(monoclinic)→ γ(cubic) phase, average crystallite size and lattice strain of Li2TiO3 ceramic at various temperatures are evaluated by X-ray diffraction patterns. The electrical properties are characterized by ac impedance spectroscopy and the experimental results show low activation energy (E a) and high ac conductivity in the range of 10−3 Scm−1for all samples at 1MHz frequency. The E a value, with respect to ac conductivity at 10kHz frequency, is approximately equal to the E a value of relaxation time (τ). The surface microstructure analysis of all sintered samples were characterized by SEM, and good crystalline nature was observed at the 1000°C sintered sample. The temperature dependence of ac conductivity distinctly indicates the negative temperature coefficient of resistance (NTCR) behavior. Conductivity mechanisms were interpreted by the frequency exponents (n 1, n 2) evaluated with the double power law followed by the Arrhenius relation. [ABSTRACT FROM AUTHOR]