Optical and magnetic properties of porous anodic alumina films embedded with Co nanowires

A simple method to tune the optical properties of porous anodic alumina (PAA) films embedded with Co nanowires (PAA@Co nanocomposite films) is reported in this paper. The films exhibit vivid structural colors and magnetic properties. The optical properties of the films can be effectively tuned by adjusting the thickness of the PAA template. The deposition of Co nanowires greatly increases the color saturation of the PAA films. The theoretical results of the changes in structural color according to the Bragg-Snell formula are consistent with the experimental results. PAA@Co films can be used in many areas, including decoration, display, and multifunctional anti-counterfeiting applications.