XRD studies on hydrothermally synthesised BaTiO_3 from TiO_2-Ba(OH)_2-NH_3 system

摘要

A detailed work on synthesis of mono-phasic barium titanate (BT) using TiO_2 powder in Ba(OH)_2-NH_3 medium at moderate temperature has been reported. Influence of various preparation parameters such as reaction temperature, reaction time, ammonia concentration and [Ba/ Ti] ratio on the formation of barium titanate was studied. The progress of reaction for formation of BT was monitored by analyzing the X-Ray diffraction data obtained under different processing conditions. To quantify the percentage of reacted titania, calibration curves were generated from synthetic mixtures of titania and pure barium titanate. Mono-phasic tetragonal barium titanate having mean crystallite diameter of 27 nm along (101) plane was formed when the reaction was earried out for 1 h at 130 deg C while keeping the initial [Ba/Ti] ratio as 1.64 and ammonia concentration as 10 M.