X-ray diffraction and microstructural studies on hydrothermally synthesized cubic barium titanate from TiO2-Ba(OH)2-H2O system

In our earlier studies synthesis of pure barium titanate (BT) from TiO2-Ba(OH)(2)-NH3 system was reported. This work describes a novel route for preparing cubic barium titanate from TiO2-Ba(OH)(2)-H2O system without addition of any mineraliser. The experimental parameters varied were: reaction time (half-an-hour to 3 h), reaction temperature (80 to 150 degrees C) and [Ba/Ti] ratio (0.92 to 1.64). The progress of reaction for formation of BT was monitored by analyzing the X-ray diffraction data obtained under different processing conditions. Mono-phasic barium titanate powder having a mean crystallite diameter (MCD) of 26 nm along (10 1) plane was formed when the reaction was carried out for 3 h at 150 degrees C. The estimated strains on the planes of the BT nano-crystals were found to be negligible. The microstructure of pure BT showed the particles to be of single crystallite nature with average size matching with the MCD value calculated from the XRD data. (c) 2006 Elsevier B.V. All rights reserved.