LEPMI - Rubrique EIP Electrocatalyse

Interfacial electrochemistry : surfaces reactivity and durability

Resp. Eric Sibert

We study the different types of activity of low-temperature electrochemical interfaces, both in terms of the reactivity of external molecules and changes in the interface itself. To that goal, we couple macroscopic measurements of electrochemical activity and numerous physical characterizations, particularly at the microscopic level, so that we can elucidate the underlying mechanisms. The characterizations can be ex situ, before or after (local probe microscopies, electron microscopies, XPS...), or before/after by identical localization microscopy (IL-TEM). Nevertheless, in situ methods (infrared spectroscopy, Raman, X-ray diffraction, etc.) are preferred when available to perform characterizations as close as possible to actual operation. We are also developing online analysis tools to detect volatile species (DEMS) or ions in solution (ICP-MS). One objective is to couple these tools to simultaneously carry out certain characterizations in situ or in line with quality electrochemical measurements to avoid interpretive artifacts and progress towards more quantitative analyses. Modelling enriches our approaches, by allowing innovative exploitation of experimental measurements but also to simulate the macroscopic effects on the behavior of interfaces. Multiphysics approaches are employed from the material scale (manometric and/or micrometric) to macro scales (systems: centimeter and meter) with the objective to access local information (pressure, temperature, etc.) or to optimize the performance of materials.
The topic is structured around the following axes: