Tuning the morphology and optical properties of one-dimensional Ag nanomaterials via anodic aluminum oxide template

One-dimensional Ag nanomaterials with different shapes have been prepared using direct-current electrodeposition within the confined nanochannels of the anodic aluminum oxide templates. The morphologies and crystal structures of the straight, Y-shaped and graded Ag nanowires are observed by field-emission scanning electron microscopy, transmission electron microscopy, and X-ray diffractometer. Absorption spectra of Ag nanowires dispersed in the ethanol are measured to reveal the relation between the morphology and the optical properties. The results indicate that the graded Ag nanowires have the higher broad band optical absorption efficiency because the diameter of the graded Ag nanowires continuously changes from 21 nm to 44 nm. These findings provide a viable and convenient route for designing shape-controlled nanowire-based high-performance photonic devices by the surface plasmon resonance of nanostructures.