Solution-Dispersible Metal Nanorings with Deliberately Controllable Compositions and Architectural Parameters for Tunable Plasmonic Response

We report a template-based technique for the preparation of solution-dispersible nanorings composed of Au, Ag, Pt, Ni, and Pd with control over outer diameter (60-400 nm), inner diameter (25-230 nm), and height (40 nm to a few microns). Systematic and independent control of these parameters enables fine-tuning of the three characteristic localized surface plasmon resonance modes of Au nanorings and the resulting solution-based extinction spectra from the visible to the near-infrared. This synthetic approach provides a new pathway for solution-based investigations of surfaces with negative curvature.