An Angle to explore nanofluidics: towards mastering ions at the nanoscale
Par Laetitia Jubin, Laboratoire de Physique Statistique ENS, Paris
Mardi 02 Avril, 14h00, Salle des séminaires (215), 2ème étage, Bâtiment A4N
Abstract :
What is so special about nanofluidics? On the one hand, it is the ultimate scale where the number of particles interacting with the surface becomes comparable to the number of particles in the volume. Thus, different behaviours from the micro or macro scale should occur, and this is a priori interesting for the physicist! On the other hand, such fundamental understanding could be applied to many systems in geology (cleaner shale gas extraction), biology (nanoporous cell membranes or neuronal structures), industry (water filtration) or energy harvesting with for instance the efficient generation of blue energy from salinity gradient. However, the field is still in its infancy not only because of the complex and various solid-liquid interface interactions that condition ion and fluid transport, but also because of the lack of experimental output.
To get a better grasp on these limitations, I will briefly give the general framework (Poisson Nernst Planck equations) as well as the experimental strategy to tackle them. I will then present three different experimental projects as a deeper illustration of this strategy. More precisely, I experimentally characterize ion transport in two model systems (electrical forcing in individual carbon nanotube and nonlinear electrical and mechanical coupling in individual glass nanocone). Eventually I develop a new printing technique that enables controlled three-dimensional additive nanometric deposition as well as printing through the ultimate nanopencil: a carbon nanotube. Mainly, from these studies we contribute respectively to the caracterisation of water-carbon interface properties, the understanding of how geometry can be harnessed to mimick advanced transport functionalities found in nature, and the design of complex nanofluidic circuits with a view to building new ionic functionalities.