Development and Application of Surface Nanocomposites Based on Tightly Packed, Hexagonally Arranged Nanoparticle Ensembles

In this work, the development of a surface nanocomposite based on tightly packed, hexagonally arranged nanoparticles, and their application for localized surface plasmon resonance (LSPR) sensing and surface-enhanced Raman spectroscopy (SERS) will be presented. A fabrication technology is introduced to create the tightly packed nanoparticle arrangements on large surface areas (in the $\mathrm{cm}^{2}$ range), where the size (diameter, $D_{0}$) and interparticle distance $(D)$ of the nanoparticles can be controlled in the $0.1\lt D/D_{0}\lt 0.8$ range. The importance of plasmonic coupling in such tightly packed nanoparticle arrangements is highlighted with numerical simulations, which were used to study and optimize the arrangements. The application of this novel surface nanocomposite for the label-free detection of short DNA fragments with LSPR, and Rhodamine 6G detection with SERS will also be demonstrated and discussed.