Tue, September 28, 2021
12:30 PM – 1:30 PM EDT over Zoom
Registration link
We welcome Dr. Michael Dickey, Camille & Henry Dreyfus Professor in the Department of Chemical and Biomolecular Engineering at North Carolina State University.
Abstract
Liquid Metals? Usually the term evokes thoughts of mercury (toxic!) or the Terminator (a villain!). Yet, gallium-based liquid metals are often overlooked despite their remarkable properties: melting points below room temperature, water-like viscosity, low-toxicity (unlike Hg), and effectively zero vapor pressure (they don’t evaporate!). They also have, by far, the largest interfacial tension of any liquid at room temperature. Normally small volumes of liquids form spherical or hemi-spherical structures to minimize surface energy. Yet, these liquid metals can be patterned into non-spherical shapes (cones, wires, etc) due to a thin, oxide skin that forms rapidly on its surface. This talk will describe efforts in our research group to harness this oxide to pattern and manipulate metal into shapes—such as wires and particles—that are useful for applications that call for soft and deformable metallic features. It is possible to pattern the metal by injection into microchannels or by direct-write 3D printing at room temperature to form ultra-stretchable wires, deformable antennas, and microelectrodes. It is also possible to remove / deposit the oxide using electrochemistry to manipulate the surface tension of the metal over unprecedented ranges (from the largest tension of any known liquid to near zero) and thereby control the shape and position of the metal for shape reconfigurable devices. This work has implications for soft and stretchable electronics; that is, devices with desirable mechanical properties for human-machine interfacing, soft robotics, and wearable electronics.
Bio
Michael Dickey received a BS in Chemical Engineering from Georgia Institute of Technology (1999) and a PhD from the University of Texas (2006) under the guidance of Professor Grant Willson. From 2006-2008 he was a post-doctoral fellow in the lab of Professor George Whitesides at Harvard University. He is currently the Camille and Henry Dreyfus Professor in the Department of Chemical & Biomolecular Engineering at NC State University. He completed a sabbatical at Microsoft in 2016. Michael’s research interests include soft matter (liquid metals, gels, polymers) for soft and stretchable devices (electronics, energy harvesters, textiles, and soft robotics).
Note: Because this month's talk is a virtual event, we will skip the speed networking and get straight to business. We hope you will eat pizza at home as we all come together as a community while keeping a safe distance. There is no deadline to RSVP.