Nanolubrication in deep eutectic solvents. Issue 36 (3rd September 2020)

• Record Type: Journal Article
• Authors: Hallett, James E.; Hayler, Hannah J.; Perkin, Susan
• Is Part Of: Physical chemistry chemical physics. Volume 22:Issue 36(2020)
• Page Start: 20253
• Page End: 20264
• Publication Date: 2020-09-03
• Subjects: Chemistry, Physical and theoretical -- Periodicals; 541.3
• DOI: 10.1039/d0cp03787g
• Languages: English
• ISSNs: 1463-9076

Abstract

Abstract : We report surface force balance measurements of the normal surface force and friction between two mica surfaces separated by a nanofilm of the deep eutectic solvent ethaline. Abstract : We report surface force balance measurements of the normal surface force and friction between two mica surfaces separated by a nanofilm of the deep eutectic solvent ethaline. Ethaline, a 1 : 2 mixture of choline chloride and ethylene glycol, was studied under dry conditions, under ambient conditions and with added water, revealing surface structural layers and quantised frictional response highly sensitive to water content, including regions of super-lubric behaviour under dry conditions and with added water. We also report exceptionally long-ranged electrostatic repulsion far in excess of that predicted by Debye–Hückel theory for a system with such high electrolyte content, consistent with previously reported observations of "underscreening" in ionic liquid and concentrated aqueous electrolyte systems [Smith et al., J. Phys. Chem. Lett., 2016, 7 (12), 2157].