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Electrowetting with Electrolytes

Charles W. Monroe¹, Leonid I. Daikhin², Michael Urbakh², and Alexei A. Kornyshev¹

¹Department of Chemistry, Imperial College, London, SW7 2AZ, United Kingdom
²School of Chemistry, Tel Aviv University, Ramat Aviv, 69978, Israel

Phys. Rev. Lett. 97, 136102 – Published 25 September, 2006

DOI: https://doi.org/10.1103/PhysRevLett.97.136102

Abstract

A theory of electrowetting is developed for systems containing an interface between two immiscible electrolytic solutions. Laws for the dependence of contact angle on electrode potential are presented. Ionic impermeability of the liquid-liquid interface and nonlinear double-layer responses rationalize observed phenomena such as contact-angle saturation and droplet contraction or detachment. The theoretical results can be applied to design new, precisely controllable microfluidic devices.

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Electrowetting with Electrolytes

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