This report summarizes the results regarding the development of composite materials based on MAXPhase or MXenes and nanoparticles of elements capable of forming bonds with sodium. The goal is to validate potential synthetic approaches for preparing anodes for sodium-ion batteries (SIB) with performance superior to that achieved during the three-year research period.
For this purpose, three classes of materials were synthesized and tested:
Composites based on MAXPhase Ti3Al1-xSnxC2 with Sn < 70%, subjected to thermal treatments in various atmospheres (Air, Argon, Sulfur) to induce nano-structuring of Sn oxide on the surface.
Nanocomposites formed by depositing antimony particles on the surface of exfoliated MXenes.
Nanocomposites based on MXenes obtained by depositing tin oxide nanoparticles on their surface, replicating the previous approach.
The first class of materials yielded excellent results in terms of a general improvement in the electrochemical performance of the nano-structured MAXPhase compared to the MXene Ti3C2 used as a reference. This new class of materials, which directly utilizes MAXPhase and ensures good storage performance through simple thermal treatments, presents a valid alternative to MXenes and their complex and critical production process for large-scale transfer.
Interesting results were obtained for MXene and antimony-based nanocomposites. Unfortunately, their good storage performance is offset by poor long-term stability, preventing their direct use in SIBs. Results for MXene/tin oxide composites were even more modest.

These activities for validating anode materials were accompanied by the preparation and testing of complete SIB cells obtained by combining the best anode and cathode materials developed by RSE during this three-year period. The experimentation produced results that exceeded the set goals, confirming the quality of the material development work conducted so far on a laboratory scale for these electrochemical storage devices.