Ag nanorod arrays tailored for surface-enhanced Raman imaging in the near-infrared region

Nanotechnology. 2008 Jul 2;19(26):265304. doi: 10.1088/0957-4484/19/26/265304. Epub 2008 May 19.

Abstract

Using a dynamic oblique angle deposition technique, we demonstrate the direct formation of Ag nanorods with quasi-parallel major axes on a template layer of oxide having a strongly anisotropic surface morphology. The optical properties of the nanorods are tuned by varying the deposition conditions without any pre- or post-treatment, and the resulting Ag nanorod arrays exhibit high surface-enhanced Raman scattering (SERS) activity. In addition to high macroscopic uniformity over a large area, our nanorod arrays contain a high density of isolated nanorods. Using the optimum Ag nanorod arrays, the SERS imaging of the microdroplets of a rhodamine 6G solution is successfully demonstrated. The space resolution of the imaging is of the order of at least a few µm. These features are suitable for the SERS imaging of biomaterials.