Synthesis of ferroelectric BaTi2O5 nanoparticles via modifying peroxopolytitanic acid solution

A peroxopolytitanic acid (Ti-IPA) solution was prepared through a direction reaction of H2O2/NH3 and metallic titanium powder. A BaTi2O5 precursor powder was prepared by a reaction of the prepared Ti-IPA and a Ba(OH)(2) aqueous solution. The obtained BaTi2O5 precursor powders were heat treated at 1000 degrees C for 10 h; the resulting BaTi2O5 was almost single phase with a particle size of approximately 200-600 nm. The Raman scattering spectra for the BaTi2O5 powders were measured at various temperatures, and the full width at half maximum (FWHM) was evaluated in low-frequency quasi-elastic scattering. From the temperature dependence of the FWHM results, the transition temperature of the resulting BaTi2O5 was 460 +/- 10 degrees C.