Hydrothermal synthesis of lead zirconium titanate (PZT) powders and their characteristics

The combined influences of KOH initial concentration and initial lead precu rsor excess on the characteristics (morphology, powder density, specific su rface area, crystalline structure and powder chemical composition) and sint ering behaviour of hydrothermally synthesised powders, have been investigat ed. Optimised conditions (low KOH concentration and presence of lead excess in the feedstock) have been determined that lend to fine deagglomerated an d reactive PZT powders densifying at about 850 degrees C. A Pb-rich surface layer has been identified over the grains, that is responsible for this lo w sintering temperature. Despite the large excess of lead, the cole of powd ers remains lead deficient. But by lowering [KOH](o), it is possible to kee p the lead deficiency within a few percent. (C) 1999 Elsevier Science Limit ed. All rights reserved.