Color properties of gold-silver alternate nanowires electrochemically grown in the pores of aluminum anodic oxidation film

Repeated electrodeposition of gold and silver on anodized aluminum plate yielded Au-Ag alternate nanowires in the geometrically anisotropic pores of the anodic oxidation films with mean diameter 10 nm and depth 10 mum, respectively. The absorption maximum wavelengths in the visible region resulting from the transverse surface plasmon resonances of Au and Ag nanorods are invariant with their growth. Consequently, the color of the anodized aluminum was simply tuned in a wide range, which is impossible to attain in each monometallic system.