Transparent, Conductive, Flexible, Stretchable Networks of Metal Nanowires
Ben Wiley, Ph.D.
Duke University
Abstract
There is an ongoing drive to replace rigid flat-panel devices (e.g. touch screens, OLED's, solar cells) with devices that are more flexible in order to improve resistance to mechanical damage, and reduce cost by enabling high-throughput, roll-to-roll production. The brittleness, and slow, vapor-based coating process (<0.01 m/s) of the standard transparent conducting material, indium tin oxide (ITO), are significant barriers to the production of low-cost, flexible electronics. This presentation will discuss the replacement of ITO with networks of metal nanowires. Metal nanowires can be produced in scalable, solution-phase syntheses, and can be coated from liquids at high rates (>1 m/s). Nanowire networks can be flexed more than 1000 times with no change in their conductance, can be made from earth-abundant metals (Cu, Ni), can carry high currents (0.5 A/cm2), can be rendered stable against oxidation, and have equivalent optoelectronic properties as ITO. I will also introduce a new mechanism - reversible sliding - that allows networks of metal nanowires to be reversibly actuated to area strains 100 times greater than the yield strain of nanowires while maintaining electrical conductivity.
Bio
Ben started at the University of Minnesota as a major in Chinese, but quickly switched to Chemical Engineering and received his B.S. in 2003. Ben received his Ph.D. in Chemical Engineering in 2007 after studying the synthesis and properties of silver nanostructures with Younan Xia in the department of chemistry at the University of Washington in Seattle. His work on silver nanowires was licensed to Cambrios, which is currently marketing silver nanowire based touch-screens. Ben subsequently worked as a postdoctoral fellow in the lab of George Whitesides in the department of chemistry at Harvard University, primarily focusing on paper diagnostics, plasmonics, and nanoskiving. Ben started as an Assistant Professor in the Department of Chemistry at Duke University in 2009. His work focuses on the production, properties, and applications of metal nanostructures. To date he has published 57 papers with over 5800 citations, has 5 patent applications, and an NSF CAREER award. He co-founded NanoForge Corp. in 2010 to commercialize his work with copper-based nanowires.
Seminar Date