PREPARATION OF PBTIO3 POWDER THROUGH OXALATE PRECIPITATION ROUTE

Pure lead titanyl oxalate (PTO) has been prepared at room temperature from a mixed aqueous solution of Pb(NO3)2, TiO(NO3)2 and oxalic acid at pH less-than-or-equal-to 0.45. The TiO(NO3)2 solution has been prepared by dissolving Ti(OH)4 in HNO3 and stabilized by maintaining the pH at less-than-or-equal-to 0.2 and storing at 10-15-degrees-C. Calcination of pure PTO yields PbTiO3 and a titania-rich phase (PbTi3O7) due to volatilization of lead. Pure PbTiO3 is obtained from a mixture of PTO and PbC2O4. Presence of the latter is necessary to compensate for lead loss during calcination. The precipitation of PTO takes place by initial formation of PbC2O4 followed by its reaction with titanyl oxalate species.