Characterization, dielectric and electrical behaviour of BaTiO₃ nanoparticles prepared via titanium(IV) triethanolaminato isopropoxide and hydrated barium hydroxide

Abstract

A new sol-precipitation technique for the preparation of nano BaTiO₃ crystallite has been developed by reacting 0·2 M each of Ti(IV) triethanolaminato isopropoxide and hydrated barium hydroxide in methanol such that the molar ratio of Ba : Ti is 1·02 at 80 °C under stirring (1200 rpm) for one hour in alkaline media using tetra methyl ammonium hydroxide (TMAH). It was calcined at 100 °C for 12 h. Structural and compositional properties were investigated by XRD, SEM, EDX, TEM, SAED and DLS techniques. FT–IR and TG–DTA were used to characterize its purity and the thermal stability. The BaTiO₃ particles prepared were found to be spherical, homogeneous and cubic in structure. The particle size was found to be 23–31 nm. The dielectric constant and dissipation factor after sintering at 400 °C were 5379 and 0·63, respectively at 100 Hz frequency. The a.c. conductivity (σ _a.c.) was found to be 2 × 10^–5 S-cm^–1 at room temperature (30 °C). It increased with increasing temperature up to 50 °C and decreased with further increase in temperature. The impedance was 3·37 × 10⁵ ohms at room temperature. It decreased with increasing frequency.