Description du sujet de thèse

Inorganic nanoparticle-assisted photothermal (PT) heating, which consists in a temperature elevation produced by given nanoparticles submitted to light irradiation, attracted a great deal of interest during several decades due to its exciting fundamental aspect and numerous applications. While gold nanoparticles are extensively studied for photothermal effects, Prussian Blue nanoparticles have gained attention for their comparable PT efficiency and stability. However, understanding photothermal heat generation remains limited to a macroscopic level, with nanoscale heat transfer still unclear. Indeed, very recently, a concept of inorganic nano-heaters as “hot spots” representing an important opening from the previously established heat diffusion theory has emerged. Yet, direct evidence for this concept is lacking, and the rational design of externally triggered "hot nano-spots" remains unexplored. Additionally, measuring the surface temperature of a single nanoparticle is an ongoing challenge.
Our project focuses on designing smart PT nanoagents aimed at improving our understanding of heat transfer at the nanometric scale. We plan to use Prussian blue nanoparticles encapsulated in a silica shell to create photothermal nano-heaters. We plan to measure temperatures in different areas to experimentally validate the existence of 'hot spots' in PT-activated environments. These measurements will provide tangible evidence and new insights into the mechanisms of photothermal heating at the nanoscale, thereby contributing to the advancement of knowledge in this field.

Contexte de travail

The project will be carried out at the Institute Charles Gerhardt Montpellier, in the Molecular Materials department. The thesis will be carried out within a group focused on the design of nanomaterials for biomedical applications. The thesis will be attached to the Ecole Doctorale Sciences Chimiques Balard (ED459) of the University of Montpellier.