Nanostructure of an ionic liquid-glycerol mixture

Area of Science:

• Physical Chemistry
• Materials Science
• Chemical Physics

Background:

• Protic ionic liquids (ILs) like ethylammonium formate (EAF) exhibit complex nanostructures.
• Understanding the behavior of ILs in mixtures is crucial for designing new materials and applications.

Purpose of the Study:

• To investigate the nanostructure of a 50:50 vol% glycerol and EAF mixture.
• To elucidate the interactions and spatial organization of glycerol and EAF at a molecular level.

Main Methods:

• Neutron diffraction was employed to probe the structure of the glycerol-EAF mixture.
• Empirical Potential Structure Refinement (EPSR) was used to model and interpret the diffraction data.

Main Results:

• EPSR analysis confirmed the nanostructured nature of the glycerol-EAF mixture.
• Electrostatic interactions drive the formation of ionic regions, while solvophobic effects create apolar domains.
• Glycerol molecules preferentially interact with EAF, forming hydrogen bonds and creating glycerol channels within the ionic domains.

Conclusions:

• The glycerol-EAF mixture exhibits distinct nanostructuring driven by specific intermolecular interactions.
• Glycerol molecules adopt different conformations and packing arrangements compared to pure glycerol due to interactions with EAF.
• The findings provide insights into the molecular organization of protic ionic liquid mixtures.