NanoScience Colloquium by Prof. Karen Edler, CAS, Dept of Chemistry, LU

Abstract:

Deep eutectic solvents (DES) are novel liquids obtained by mixing two strongly interacting species to form a room-temperature liquid. They have useful tuneable solvent properties, including low toxicity and sustainability. 

We aim to use these solvents to grow nanostructured oxide materials, both nanoparticles and nanoporous materials, formed using micelle templating. We have found that polar DES will support amphiphile aggregation and so are undertaking a systematic study to correlate the unique hydrogen-bonded nanostructure of DES with surfactant phase behaviour in these solvents. We use a range of scattering techniques, including small angle scattering and reflectivity as well as measurements of critical micelle concentration, rheology and thermal properties to study micellization and formation of liquid crystalline phases in these media. 

These investigations have shown that DES can promote amphiphile self-assembly but alter surfactant phase behaviour significantly compared to water, as the solvent components can be tuned to be interacting or non-interacting with the surfactant, changing the micelle shape. We have also explored the formation of cerium oxide and iron oxide nanoparticles, and the generation of mesoporous micelle-templated cerium oxides. This presentation will discuss our results and try to draw conclusions on the important factors controlling amphiphile behaviour, nanoparticle growth and micelle templating in these interesting novel solvents.