Direct synthesis of ultrafine tetragonal BaTiO(3 )nanoparticles at room temperature

A large quantity of ultrafine tetragonal barium titanate (BaTiO(3)) nanoparticles is directly synthesized at room temperature. The crystalline form and grain size are checked by both X-ray diffraction and transmission electron microscopy. The results revealed that the perovskite nanoparticles as fine as 7 nm have been synthesized. The phase transition of the as-prepared nanoparticles is investigated by the temperature-dependent Raman spectrum and shows the similar tendency to that of bulk BaTiO(3 )materials. It is confirmed that the nanoparticles have tetragonal phase at room temperature.