CRYSTAL-GROWTH OF LEAD-ZIRCONATE-TITANATE WITH ADDITIVES UNDER HYDROTHERMAL CONDITIONS

Single crystals of lead zirconate titanate (PZT) with an additive such as La2O3, Nb2O3 or MnO were grown under hydrothermal conditions with the starting nutrient of PZT ceramic powder based on Pb(Zr0.53Ti0.47)O -3. The powder placed at the bottom of the capsule was dissolved in th e KF solution at 640 degrees C, and recrystallized at the top of the c apsule at 600 degrees C. Large crystals up to 1.8 mm in length were gr own in 45 wt% KF solution, but a decrease in the concentration resulte d in the reduction of the volume and size of the grown crystals. The a ddition of Nb to PZT ceramics inhibited the growth of the crystals. Th e additives in the starting materials were incorporated into the grown crystals, but the concentration of Zr in the crystals was markedly re duced in comparison with that; of the starting materials.