Séminaire d'Institut

Mardi 1^er Décembre 2026 à 10h30.

2D materials under an X-ray microscope: What can we learn about MXenes ?

''
Finding efficient ways to store and deliver electrical energy is urgently needed for the large-scale development of renewable energy sources. The use of pseudocapacitive materials, such as 2D transition metal carbides and nitrides, so-called MXenes, is a promising solution to achieve electrochemical energy storage with high power and energy densities. Nevertheless, local electrochemical processes occurring at the MXene-electrolyte interface are currently largely unexplored.

In this seminar, I will present the nanoscale chemical imaging of individual MXene flakes during intercalation reactions. To this aim, synchrotron-based in situ scanning X-ray microscopy (SXM) will be introduced, enabling X-ray absorption spectroscopy characterization with sub-50 nm spatial resolution.1 The intercalated species can be imaged at the single MXene flake level using an in situ holder enabling imaging in liquid.2 In situ X-ray imaging during an electrochemical reaction is also possible to monitor faradaic reactions at the MXene surface.3 We will compare spontaneous and electrochemical intercalation of protons and Li+ ions in MXene flakes and discuss related chemical changes of the chemical bonding at the surface of the MXenes.

References

1. Amargianou, F. et al. Nanoscale Surface and Bulk Electronic Properties of Ti3C2Tx MXene Unraveled by Multimodal X-Ray Spectromicroscopy. Small Methods 8, 2400190 (2024).
2. Amargianou, F. et al. Water-Induced Local Redox Reactions on Individual Ti3C2Tx MXene Flakes in Aqueous Environment. Angew. Chemie Int. Ed. 65, e20508 (2026).

3. Sharma, N. et al. Nanoscale chemical imaging of pseudocapacitive charge storage in MXenes. Energy Environ. Sci. 19, 680–690 (2026).

''