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Title: Liquid metal actuation by electrical control of interfacial tension

Abstract

By combining metallic electrical conductivity with low viscosity, liquid metals and liquid metal alloys offer new and exciting opportunities to serve as reconfigurable components of electronic, microfluidic, and electromagnetic devices. Here, we review the physics and applications of techniques that utilize voltage to manipulate the interfacial tension of liquid metals; such techniques include electrocapillarity, continuous electrowetting, electrowetting-on-dielectric, and electrochemistry. These techniques lower the interfacial tension between liquid metals and a surrounding electrolyte by driving charged species (or in the case of electrochemistry, chemical species) to the interface. The techniques are useful for manipulating and actuating liquid metals at sub-mm length scales where interfacial forces dominate. We focus on metals and alloys that are liquid near or below room temperature (mercury, gallium, and gallium-based alloys). The review includes discussion of mercury—despite its toxicity—because it has been utilized in numerous applications and it offers a way of introducing several phenomena without the complications associated with the oxide layer that forms on gallium and its alloys. The review focuses on the advantages, applications, opportunities, challenges, and limitations of utilizing voltage to control interfacial tension as a method to manipulate liquid metals.

Authors:
;  [1]
  1. Department of Chemical and Biomolecular Engineering, North Carolina State University, 911 Partners Way, Raleigh, North Carolina 27695 (United States)
Publication Date:
OSTI Identifier:
22594411
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Reviews; Journal Volume: 3; Journal Issue: 3; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; ALLOYS; ELECTRIC CONDUCTIVITY; ELECTROCHEMISTRY; GALLIUM; LIQUID METALS; MERCURY; SURFACE TENSION

Citation Formats

Eaker, Collin B., and Dickey, Michael D., E-mail: michael-dickey@ncsu.edu. Liquid metal actuation by electrical control of interfacial tension. United States: N. p., 2016. Web. doi:10.1063/1.4959898.
Eaker, Collin B., & Dickey, Michael D., E-mail: michael-dickey@ncsu.edu. Liquid metal actuation by electrical control of interfacial tension. United States. doi:10.1063/1.4959898.
Eaker, Collin B., and Dickey, Michael D., E-mail: michael-dickey@ncsu.edu. 2016. "Liquid metal actuation by electrical control of interfacial tension". United States. doi:10.1063/1.4959898.
@article{osti_22594411,
title = {Liquid metal actuation by electrical control of interfacial tension},
author = {Eaker, Collin B. and Dickey, Michael D., E-mail: michael-dickey@ncsu.edu},
abstractNote = {By combining metallic electrical conductivity with low viscosity, liquid metals and liquid metal alloys offer new and exciting opportunities to serve as reconfigurable components of electronic, microfluidic, and electromagnetic devices. Here, we review the physics and applications of techniques that utilize voltage to manipulate the interfacial tension of liquid metals; such techniques include electrocapillarity, continuous electrowetting, electrowetting-on-dielectric, and electrochemistry. These techniques lower the interfacial tension between liquid metals and a surrounding electrolyte by driving charged species (or in the case of electrochemistry, chemical species) to the interface. The techniques are useful for manipulating and actuating liquid metals at sub-mm length scales where interfacial forces dominate. We focus on metals and alloys that are liquid near or below room temperature (mercury, gallium, and gallium-based alloys). The review includes discussion of mercury—despite its toxicity—because it has been utilized in numerous applications and it offers a way of introducing several phenomena without the complications associated with the oxide layer that forms on gallium and its alloys. The review focuses on the advantages, applications, opportunities, challenges, and limitations of utilizing voltage to control interfacial tension as a method to manipulate liquid metals.},
doi = {10.1063/1.4959898},
journal = {Applied Physics Reviews},
number = 3,
volume = 3,
place = {United States},
year = 2016,
month = 9
}
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