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Updated: Mar 28, 2026

A Method to Manipulate Surface Tension of a Liquid Metal via Surface Oxidation and Reduction
Published on: January 26, 2016
Self-Actuation of Liquid Metal via Redox Reaction
Ryan C Gough1, Jonathan H Dang1, Matthew R Moorefield1
1College of Engineering, University of Hawaii , 2540 Dole Street, Holmes Hall 483, Honolulu, Hawaii 96822, United States.
Abstract:
Presented here is a method for actuating a gallium-based liquid-metal alloy without the need for an external power supply. Liquid metal is used as an anode to drive a complementary oxygen reduction reaction, resulting in the spontaneous growth of hydrophilic gallium oxide on the liquid-metal surface, which induces flow of the liquid metal into a channel. The extent and duration of the actuation are controllable throughout the process, and the induced flow is both reversible and repeatable. This self-actuation technique can also be used to trigger other electrokinetic or fluidic mechanisms.
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