Hydrothermal Synthesis of Dy-Doped BaTiOs Powders

Submicron-siz.ed (~200 nm), monodisperse, and spherical powders of pure and dysprosium (Dy)doped (0.8 at. pet) BaTiO3 have been prepared by "hydrothermal synthesis" at 90 °C in an air atmosphere. The powder preparation procedure developed in this work did not necessitate the use of strict and expensive processes, which were commonly required for the removal of free CO2 present in the atmosphere. The prepared powders were found to be crystalline, pure, and contained no BaCO^ as an impurity phase. Pure and Dy-doped BaTiO3 powders synthesized at 90 °C had the pseudocubic (space group: Pm-3m) crystal structure. Grain growth characteristics of pure and Dy-doped BaTiO^ pellets were compared during sintering in air over the temperature range from 1200 °C to 1500 °C. The Dy doping was found to be significantly effective in inhibiting the anomalous grain growth in BaTiO3 samples heated at or above 1200 °C.