Preparation and dielectric properties of order nanoporous TiO 2 /PAA film

Polycrystalline order nanoporous TiO2/PAA (porous anodic alumina) composite films have been prepared by reactive DC magnetron sputtering technique at room temperature. The crystalline phase and morphology of the deposited film were investigated by X-ray diffraction spectra (XRD) and scanning electron microscopy (SEM), respectively. The results showed that the post-annealing treatment could facilitate film crystallization. The influences of pore diameter and electric field frequency on the dielectric properties of TiO2/PAA samples were systematically studied. It was found that the dielectric properties of the films depended on the pore diameters. The unipolar polarization–electric field loops for all the samples were evaluated. Interestingly, lower remnant polarization was found in the bigger pore diameter TiO2/PAA composite films, suggesting high energy storage and low loss of the sample.