title: Enhanced capacitance of composite anodic ZrO₂ films comprising high permittivity oxide nanocrystals and highly resistive amorphous oxide matrix.
abstract: Anodic oxide films with nanocrystalline tetragonal ZrO(2) precipitated in an amorphous oxide matrix were formed on Zr-Si and Zr-Al alloys and had significantly enhanced capacitance in comparison with those formed on zirconium metal. The capacitance enhancement was associated with the formation of a high-temperature stable tetragonal ZrO(2) phase with high relative permittivity as well as increased ionic resistivity, which reduces the thickness of anodic oxide films at a certain formation voltage. However, there is a general empirical trend that single-phase materials with higher permittivity have lower ionic resistivity. This study presents a novel material design based on a nanocrystalline-amorphous composite anodic oxide film for capacitor applications.
authors.affiliation: Division of Materials Chemistry, Faculty of Engineering, Hokkaido University, Sapporo, Hokkaido 060-8628, Japan. habazaki@eng.hokudai.ac.jp
authors.forename: Hiroki
authors.initials: H
authors.lastname: Habazaki
authors.forename: Shun
authors.initials: S
authors.lastname: Koyama
authors.forename: Yoshitaka
authors.initials: Y
authors.lastname: Aoki
authors.forename: Norihito
authors.initials: N
authors.lastname: Sakaguchi
authors.forename: Shinji
authors.initials: S
authors.lastname: Nagata