Probing the reactivity of nano-objects in a confined chemical environment

This project aims to study the effect of confinement on the properties of individual nano-objects. The questions raised are: what role can the nanoenvironment play on the properties of plasmonic nanoparticles and on their interactions? In their reactivity and catalytic activity? Combining a new micro/nano fabrication technique recently developed in our team [1], a versatile surface modification procedure based on covalent grafting from diazonium salts[2] and a reactivity monitoring methodology based on electrochemical microscopy [3], this thesis will focus on acquiring a fundamental understanding of plasmonic nanochemistry under controlled confinement conditions.
Combining microfabrication and electrochemical microscopy under optical control, we will study the confinement of plasmonic nanoparticles in nanocavities with controlled chemical properties thanks to the introduction of specific functions. From the dynamics of the nanoparticle inside the cavity and its opto-electrochemical response, we will analyze its interaction with the environment and its reactivity, in particular the evolution of its plasmonic properties and its ability to catalyze chemical reactions. Thanks to the realization of these nanocavities, we will also be able to produce by electrochemistry some nanostructures of predefined size and geometry, such as nanowires of conjugated polymers between the substrate and the microelectrode.
With these studies at the scale of single nano-objects, we offer a holistic approach where each chemical event can be observed and analyzed quantitatively, allowing the rational development of specific designs that can be controlled not only by confinement within a nanocavity but also by the chemical environment thanks to the presence of specific functions on the surface. This dual approach of spatial and chemical control should make it possible to better understand the interactions governing reactivity at the nanometric scale.

For more information, contact Pr F. Miomandre

You can apply on the dedicated website of the Université Paris-Saclay