Rheo-Dielectric Study of MXene-Based Pickering Emulsions

Using MXene nanosheets as stabilizers in emulsion-templating offers a promising route for fabricating conductive composites with low percolation thresholds. The MXene network formed at the droplet interfaces, combined with the emulsion microstructure, gives rise to a gel-like material exhibiting strong electrical percolation. This study unravels the relationship between, on the one hand, the microstructure and, on the other hand, the viscoelastic and functional properties of MXene-stabilized emulsions. This is achieved by combining interfacial and bulk characterization techniques, including interfacial and bulk rheology, broadband dielectric spectroscopy, and microscopy. Interfacial measurements revealed a clear link between the rheological behavior and electrical conductivity of the MXene interfacial network. In the bulk, the characterization of MXene-based Pickering emulsions showed that the overall conductivity depends on both the interfacial network and the droplet-droplet interactions. Finally, through rheo-dielectric and rheo-optical characterizations, we demonstrate that the emulsion microstructure influences the electrical conductivity and rheological properties of MXene-stabilized emulsions under shear flow and their recovery after shear.