From hollow gold nanoparticles to gold nanorings: Morphological tunability of the plasmonic response

TL;DR

This paper demonstrates how the morphological and optical properties of hollow gold nanoparticles can be precisely tuned using a wet chemistry method with PLL, enabling versatile plasmonic applications.

Contribution

It introduces a controlled wet chemistry approach to modify hollow gold nanoparticles' morphology and plasmonic response, offering an alternative to lithography.

Findings

Plasmonic response can be finely tuned through morphological modifications.

Electron energy loss spectroscopy reveals detailed plasmon excitations.

Simulations confirm the experimental control over optical properties.

Abstract

The optical and morphological properties of hollow gold nanoparticles (HGNPs) can be finely modified by employing Poly-L-Lysine hydrobromide (PLL), an homo poly aminoacid of the L-lysine, used as reducer and stabilizer. We investigate locally the plasmonic response of these nanostructures by electron energy loss spectroscopy (EELS). The plasmon excitations are interpreted by discrete dipolar approximation (DDA) simulations. We demonstrate that this controlled top-down morphological modification a fine tuning of the optical response is possible. Unlike the traditional lithographic techniques, this has been achieved in a controlled manner using wet chemistry, enabling the potential use of these nanostructures for a broad range of plasmonic applications, including biomedicine, catalysis and quantum communications.