Hydrothermal synthesis of BaZrO₃ fine particles controlled in size and shape and fluorescence behavior by europium doping

Monodispersed barium zirconate (BaZrO₃) fine particles with high crystallinity have been synthesized by hydrothermal reactions using barium hydroxide and a Zr-triethanolamine complex. The particle shape was controlled by changing initial Ba²⁺ and Zr⁴⁺ concentrations, and sphere-, rhombic dodecahedral-, and flower-shaped BaZrO₃ fine particles were obtained. On the other hand, the particle mean size of the BaZrO₃ microspheres was precisely controlled by the addition of NaOH into the precursor solutions. By Eu-doping, the present BaZrO₃ synthesis was also applied to investigate the effect of size and shape on the fluorescence properties of BaZrO₃ for its use as a phosphor. The asymmetric ratio of the photoluminescence intensity of the resulting Eu-doped BaZrO₃ powders suggested that the particles obtained by the present method had a basically single crystalline structure.