Structure and optical and dielectric properties of barium titanate nanoparticles obtained by the mechanochemical method

The parameters of mechanochemical synthesis of barium titanate nanoparticles from barium titanyl oxalate and an oxide mixture are optimized. X-ray phase analysis, infrared and Raman scattering spectroscopy, differential scanning calorimetry, and dielectric spectroscopy are applied to demonstrate that the nanoparticles contain the cubic and tetragonal crystal lattice modifications. The impurity spectra for the particles obtained by the mechanochemical method from different initial substances are identical. The ferroelectric phase volume increases as hydroxyl groups are annealed from the crystal lattice and decreases upon annealing of metal atom vacancies.