Morphology Modulation of Ionic Surfactant Micelles in Ternary Deep Eutectic Solvents

Area of Science:

• Physical Chemistry
• Materials Science
• Supramolecular Chemistry

Background:

• Deep eutectic solvents (DES) are emerging as sustainable alternatives to traditional solvents.
• DES can facilitate the self-assembly of amphiphilic molecules, but factors influencing this process require detailed investigation.
• Understanding surfactant-DES interactions is key to controlling self-assembly.

Purpose of the Study:

• To investigate the micellization of cationic (CTAB) and anionic (SDS) surfactants in a ternary DES.
• To explore the influence of DES composition on micelle morphology.
• To elucidate the relationship between DES components, counterion solubility, and micelle shape.

Main Methods:

• Small-angle neutron scattering (SANS) was employed to study surfactant self-assembly.
• A ternary DES composed of choline chloride, urea, and glycerol was used.
• Varying molar ratios of hydrogen bond donors in the DES were systematically analyzed.

Main Results:

• Both globular and rodlike micelles were formed, depending on the DES composition.
• The degree of micelle elongation directly correlated with the DES composition.
• Counterion solubility in the DES significantly impacts micelle morphology, especially at lower glycerol content.

Conclusions:

• DES composition offers precise control over surfactant micelle shape and size.
• Tailoring micelle morphology in DES opens avenues for rheology control.
• This control is valuable for templated synthesis of porous materials with tunable pore structures.