Study of Matter in Environmental Conditions (L2ME)

The research group “Study of the Matter in Environmental Conditions” results from the fusion between the LDD (Diffusion and Diffraction group) and the LM2E (Microscopy under Environmental Conditions) group which took place in January 2014.

The control of the sample environmental conditions, in the field of electron microscopy, allows observing directly objects that are generally not observable by the conventional imaging techniques. This paves the way to in situ experiments and this can yield to the measurement of physical parameters and activation energies. As an example, recent advances in the field of soft X-ray microscopy and electron microscopies allow the direct observation of supramolecular aggregates in solution with a very high resolution, without any specific sample preparation and with unexpected spatial and time resolutions.

Coupling specific stages or cells (controlled relative humidity or high temperature) with modern electron microscopes allows the precise characterization of physico-chemical properties such as self-healing, sintering, dissolution, chemical reactivity through in situ experiments.

In parallel, a multi-scale approach for matter characterization ranging from the nanometer to the micrometer scale is developed. It relies on the mastering of measurements of small-angle scattering and diffraction using hard X-rays. Therefore, physico-chemical data including interaction potentials, fractal interfaces and curvatures can be directly determined by simultaneously controlling temperature and solvent activity.

This approach is completed with the instrumental development of specific tools, based on the know-how of the lab team with the aim to answer specific research objectives. These developments cover small tools (sample holders, etc), stages with dedicated applications or the complete refurbishing of apparatus.

The skills of the team in terms of instrumentation and interpretation of XRD and SAXS spectra, as well as in the recording of electron microscopy images and image processing, allow developing original technical methodologies. The know-how of L2ME team is shared with other research teams, yielding to the obtaining of original scientific data and results.