INSP - Sorbonne Université - 4 place Jussieu - 75005 Paris - Barre 22-32, 2e étage, salle 201
Léo Bossard-Giannesini, doctorant dans l’équipe Physico-chimie des surfaces
Abstract
Gold nanoparticles are generally associated to their plasmonic properties, responsible for the absorption band in the visible, and they are also interesting for their electronic properties. For this last type of application, an essential property could be studied, the work-function. It provides the access to the charge state of the particle, which is influential in the plasmon response.
In our work, we have measured the work-function modification of the gold nanoparticles, induced by the post-functionalization of their surface with a thiol molecule. The work-function was measured with a conductive atomic force microscope, a Kelvin Probe (KPFM). Two different functionalizations, an acid carboxylic and an amine, have been compared and give two different work-function modifications. The measured work-functions also evolve as a function of the nanoparticle size. The effect of the functionalization on the plasmon band has also been measured.