LANGMUIR-BLODGETT-FILMS PREPARED FROM FERROELECTRIC LEAD ZIRCONIUM TITANATE PARTICLES

The preparation of monoparticle-thick Langmuir films from 70-nm, lauri c acid-coated (dispersion I) and alcohol-coated (dispersion II) ferroe lectric lead zirconium titanate (PZT) particles is described. Surface pressure (IT) vs surface area (A) isotherms, in situ on the water surf aces, atomic force microscopic (AFM), and electron microscopic (TEM) i mages, ex situ after their transfer to substrates, established the pre sence of monoparticles with appreciable and variable interparticle dis tances (dispersion I) and relatively densely packed monoparticles (dis persion II) in the Langmuir films. Langmuir-Blodgett (LB) films were f ormed by the monoparticulate layer by monoparticulate layer transfer o f the PZT film to substrates (glass slides coated by 500-Angstrom gold or indium tin oxide). Good transfer ratios (up to eight layers) were obtained if each transferred PZT film was fixed by a methanol:ethanol: 2-propanol solution of lead(II) acetate, zirconium(IV) butoxide, and t itanium-(TV) isopropoxide taken in stoichiometric amounts for Pb(Zr0.5 Ti0.5)O and cured at 80 degrees C for 1.5 min. Ferroelectric propertie s of the LB films, prepared from dispersion II, have been demonstrated by polarization measurements using a Sawyer-Tower circuit.