Synthesis and characterization of PZT fibers via sol-gel

A fiber forming PZT gel containing 58.5 wt% PZT was synthesized by using zi rconium-n-propylate, titanium-iso-propylate, lead acetate and butoxyethanol . Unseeded PZT gels and gels containing 0.5 wt% PZT perovskite seeds (empty set = 200-300 nm) could be extruded through a monofilament nozzle (empty s et = 100 mu m) at pressures between 50 and 150 bar, whereas PZT gels, conta ining 1 and 2 wt% PZT particles, were pressed through the nozzle at higher pressures (200-300 bar). The microstructure of unseeded and seeded (0.5, 1, 2 wt% PZT) PZT fibers was characterized by SEM. Unseeded fibers had three different shells at 450 degrees C: an external dense shell(approx. 200 nm t hick), a middle shell consisting of a porous structure (1.5 mu m thick) and the center of the fiber, characterized by a matrix containing globular par ticles. At 700 degrees C, a 200-250 nm thick and dense external shell and a porous fiber interior were be observed. 2 wt% of PZT seeds was necessary t o densify the fiber completely. The seeds were located in the center of eac h PZT perovskite rosette.