Seminar: “In-Plane and Out-of-Plane Deformation of 2D Materials and 2D-Materials-Based Bioelectronics”
Two-dimensional (2D) materials have exhibited many unique functionalities and properties.Their atomic thinness and mechanical robustness make them promising candidate for next generation flexible, stretchable and bio-integrated electronics. Through combined experimental and theoretical investigations, this talk unveils the in-plane stretchability of 2D materials as well as their out-of-plane deformation through nano-bubbles and nano-tents. We will show that both in-plane and out-of-plane deformation are largely affected by the underlying substrate. In fact, out-of-plane deformation also induces in-plane strain and strain gradient. By examining experimentally measured profiles of a variety of nano-bubbles and nano-tents, we found all of them to collapse into a unified power law. Using the membrane limit of the Föppl–von Kármán equations, we can analytically solve the in-plane strain field in the nano-bubbles and nano-tents, which has been validated via Raman mapping. Moreover, by measuring the profiles of the nano-bubbles, nano-tents, and the radial buckles surrounding them, 2D materials-to-substrate interface properties such as adhesion and shear strength can be readily extracted. As indented drumhead specimens are essentially inverse tents, their force-displacement relations will be revisited.
About the Speaker
Dr. Nanshu Lu is currently Temple Foundation Endowed Associate Professor at the University of Texas at Austin. She received her Ph.D. from Harvard University and then Beckman Postdoctoral Fellowship at UIUC. Her research concerns the mechanics, materials, manufacture and human integration of soft electronics. She has published more than 80 journal articles with more than 12,000 citations. She has been named 35 innovators under 35 by MIT Technology Review and has received NSF CAREER Award and multiple DOD Young Investigator Awards.