Dissipation mechanisms in ionic liquids

The spreading of ionic liquids on molecularly smooth solid surfaces has been little studied in the past. We show that the spreading behaviors of the two ionic liquids, [EMIM] ethyl sulfate and ECOENG™ 500, are well described by the combined molecular kinetic and hydrodynamic model of de Ruijter, de Coninck, and Oshanin [M.J. de Ruijter, J. de Coninck, G. Oshanin, Langmuir 15 (1999) 2209] with reasonable values for the molecular friction coefficient ζ, molecular displacement λ, and frequency K0 associated with contact line motion, as well as reasonable values for the microscopic cutoff a associated with hydrodynamic dissipation.

Ionic liquid droplets dissipate energy via viscous flow and contact line friction as they spread across a molecular smooth silicon wafer.Figure optionsDownload as PowerPoint slide