Effect of Excess PbO on Phase Formation and Microstructure of (Pb0.975Ba0.025)TiO3 Powders

Abstract

In this work, we studied the effect of excess PbO doping on the lead barium titanate powders [(Pb0.975Ba0.025)TiO3;(PBT2.5)]. PBT2.5 were prepared via mixed oxide method with various of excess PbO level (-3, 0, 1, 3, 5, 10 wt%). The excess PbO added to compensates loss from
evaporation during calcination at 800 oC for 1 h. The crystal structure and microstucture of lead
barium titanate powders were analyzed by X-ray diffractrometer (XRD) and Scanning Electron
Microscope(SEM), respectively. It was found that lead barium titanate powders indexed in
tetragonal structure. Furthermore, The impurities phases of lead oxide (PbO), titanium oxide (TiO),
and leaddioxide (PbO2) were detected in the higher than 1 wt% excess PbO samples. The c/a ratio,
the cell volume were increased and average paticle sizes were increased with increasing of excess
PbO levels.

Keywords: lead barium titanate, tetragonality, mixed oxide, excess PbO