The 0−3 metal oxide−isotactic polypropylene nanocomposites are synthesized via in situ propylene polymerization using the C 2-symmetric metallocene catalyst dichloro[rac-ethylenebisindenyl]zirconium(IV) (EBIZrCl2) immobilized on methylaluminoxane (MAO)-treated barium titanate (BaTiO3) or titanium dioxide (TiO2) nanoparticles. The composite materials are characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and 13C nuclear magnetic resonance (NMR) spectroscopy. It is shown that the nanoparticles are homogeneously dispersed in the polyolefin matrices. Electrical measurements reveal nanocomposite leakage current densities of ∼10-6 to 10-9 A/cm2, permittivities as high as 6.1, and breakdown strengths of ∼4 MV/cm. Energy densities are estimated to be as high as 9.4 J/cm3.

Antiferroelectric (AFE) Pb0.92La0.08Zr0.95Ti0.05O3 (PLZT) films were grown on nickel foils with lanthanum nickel oxide buffer by chemical solution deposition. We observed field-induced AFE-to-ferroelectric (FE) phase transition. The electric field for the AFE-to-FE phase transition (EAF ≈ 270 kV/cm) and that for the reverse phase transition (EFA ≈ 230 kV/cm) were measured at room temperature on samples with PLZT films of ≈1-µm thickness. Relative permittivity of ≈560 and dielectric loss of <0.05 were measured near zero DC bias field. Hysteresis loop analysis showed that energy densities of ≈53 and 37 J/cm3 can be stored and recovered from the film-on-foil capacitors at 25 and 150 °C, respectively. Highly accelerated life tests were conducted. The projected mean time to failure is >5000 h when the capacitors are operated at room temperature with an applied field of ≈300 kV/cm.