Sintering of dense ceramics bodies of pure lead titanate obtained by seeding-assisted chemical sol-gel

Crack-free and dense lead titanate ceramics (similar to 97% of the theoretical density) has been prepared by a sol-gel method using titanium tetrabutoxide and lead acetate in stoichiometric proportion and without the additions of dopants. Crystalline nanometer-sized PbTiO3 seeds have been added to the precursor solution in a proportion of 10 wt%, allowing the preparation of pure PbTiO3 perovskite phase at temperatures as low as 400 degreesC. The remanent polarization of sintered samples was 1.73 muC/cm(2) and the coercive field 33 kV/cm. These values were in agreement with those reported for dense PbTiO3. The Curie temperature was around 440 degreesC, slightly lower than the theoretical value (490 degreesC). It was observed that an increase in the sintering temperature and grain size resulted in an increase in the tetragonal distortion of the perovskite phase. (C) 2001 Elsevier Science Ltd. All rights reserved.