The CNRS, through the program "Biomimetism Challenge"("Défi Biomimétisme") has awarded us a one-year project to explore the development of bio-inspired graphene origami structures for NEMS development...
« High-pressure effect on the optical extinction of a single gold nanoparticle» in ACS Nano.
We have developed the first experimental method to quantitatively measure the optical absorption of an individual nanoparticle at very high-pressure (~10 GPa)...
I have organized a one day workshop about pedagogical approaches in science and engineering : follow the link to CEP2019 !
The effect of pressure – by definition a 3‐dimensional concept – on 2‐dimensional systems brings a number of fundamental questions, which have been partly answered through newly engineered samples and experimental setups. In this review of the high‐pressure Raman studies of graphene, we underline the importance of the presence of a supporting substrate and its role for the production of biaxial strain conditions in high pressure experiments...
We have been able to change the dimensionality of carbon nanocarbons from 1D to 2D. The action of very high pressures on triple-walled carbon nanotubes lead first to their radial collapse, followed by the unzipping of the collapsed tubes and the formation of graphene nanoribbons. The investigation included the use of Raman spectroscopy, high resolution electron microscopy and atomistic molecular dynamics modelling. The study opens a new route for graphene production...
We have shown that using high pressure we can create a new type of 1-dimensional system. This new carbon polymorphe is obtained from a linear chain of carbon atoms (in red in the top figure) encapsulated inside a double-wall carbon nanotube. At high pressures the nanotube deforms allowing the formation of new bonds between the chain (in blue in the bottom figure) and the nanotube wall (in black)...
Together with Colin Bousige, Alexis Forestier, Matthieu Mercury we prepared a workshop entitled "Jeux de Nanoscience". Together with the many other workshops, we recived more than 1200 visitors in one day !
We have shown that the mechanics of single-wall carbon nanotubes cannot be assimilated to the one of macroscopic tubes. At the meso-nanoscale, the continnuum mechanics approach breaks and needs to be replaced by an atomistic view. Our combined experimental and theoretical study, has allowed us to determine a correction to the Lévy-Carrier law (continuum mechanics) to describe the radial collapse of tubes under pressure....
We propose a model for the pressure induced radial collapse of nanotubes with a few number of walls. The proposed model deviates from continous mechanics predictions. This deviations are due to atomic discretization of the compliances for diameters smaller than about 1nm and due to tube-tube interactions for larger tubes...
We have shown that an atomic-layer of MoS2 deposited on a glass surface is made of a composition of zones in adhesion with the surface and other zones which remain unbounded. MoS2 being a semiconductor it is proposed as an alternative to graphene. We have shown that MoS2 sticks to surfaces in a very different way than graphene, which on its side tends to do it homogeniously...