CRYSTALLIZATION OF LEAD TITANATE PREPARED BY WET CHEMICAL METHODS

The crystallization behavior of PbTiO3 powder prepared by sol-gel and coprecipitation techniques was investigated by DTA, XRD, and Raman spectral analyses. PbTiO3 precursor powders were derived from a mixed solution of Pb(NO3)2 and TiCl4 at 40-degrees-C and pH of 9.0 to 9.7. The dried gel and coprecipitated powders are both amorphous but have different structures. The room-temperature Raman spectra from heat-treated powders changed continuously from an amorphous to a crystalline state with increasing annealing temperature. By annealing coprecipitated powders, a dramatic change in the Raman spectra, caused by the structural relaxation as the annealing temperatures increased, was clearly visible, i.e., coprecipitated, gel, and crystalline structure, in turn.