Work

Structure formation due to antagonistic salts

Year: 2016

Type: review

Abstract: Antagonistic salts are composed of hydrophilic and hydrophobic ions. In a mixture solvent (water–oil) such ion pairs are preferentially attracted to water or oil, giving rise to a coupling between the charge density and the composition . First, they form a large electric double layer at a water–oil interface, reducing the surface tension and producing mesophases. Here, the cations and anions are loosely bound by the Coulomb attraction across the interface on the scale of the Debye screening length. Second, on solid surfaces , hydrophilic (hydrophobic) ions are trapped in a water-rich (oil-rich) adsorption layer, while those of the other species are expelled from the layer. This yields a solvation mechanism of local charge separation near a solid. In particular, near the solvent criticality, disturbances around solid surfaces can become oscillatory in space. In mesophases, we calculate periodic structures , which resemble those in experiments.

Source: Current Opinion in Colloid & Interface Science

DOI: 10.1016/j.cocis.2016.02.007

Authors: Akira Onuki, Shunsuke Yabunaka, Takeaki Araki, Ryuichi Okamoto

Institutions: Kyoto University, Yukawa Institute for Theoretical Physics, Tokyo Metropolitan University

Language: English

Topic: Electrostatics and Colloid Interactions

Subfield: Physical and Theoretical Chemistry

Field: Chemistry

Domain: Physical Sciences

Open Access status: hybrid

Estimated APC paid: $4,210

Funder: Japan Society for the Promotion of Science