Seminar by Weinan Xu
From 3D Macromolecules to 3D Scalable Micro/Nano Manufacturing
Department of Chemical and Biomolecular Engineering
Johns Hopkins University
Micro/nano manufacturing generally refers to lithography based micro-electromechanical systems fabrication, which has achieved great success over the past several decades, but has major limitations in materials selection and the generation of complex 3D structures with high aspect ratios. Moreover, smart micro/nano structures with the abilities to adapt and respond to external stimuli, through their changes in size, shape, mechanical or optical properties, cannot be easily generated with traditional manufacturing techniques. In this talk, new strategies to fabricate 3D smart micro/nanostructures in an efficient and scalable manner will be introduced, which combine top-down fabrication and bottom-up assembly. The materials used for 3D fabrication include responsive polymers with branched architecture, as well as 2D nanomaterials such as graphene and transition metal dichalcogenides. Their conformation, assembly and interactions will be studied at the molecular level. The strategies used to generate 3D smart structures include layer-by-layer assembly and self-folding, which enable the molecular level control of the internal structure, and the generation of complex 3D geometries from 2D precursors. Those smart 3D micro/nano structures with ultrathin shell provide a novel and high-performance platform for drug delivery, biosensing, bioelectronics and energy applications.
Weinan Xu is a postdoctoral fellow in the Department of Chemical and Biomolecular Engineering at Johns Hopkins University since Jan 2016, he received his PhD degree in Materials Science and Engineering from Georgia Institute of Technology in 2015, and his B.S. degree in Polymer Science and Engineering from Donghua University, China (2011). His current research is focused on advanced design, fabrication and manufacturing of soft micro/nanostructures based on responsive polymers and 2D nanomaterials. Weinan has published 19 peer-reviewed papers in high-impact journals such as Science Advances, ACS Nano, Angewandte Chemie and Macromolecules. He was recognized with several awards including Excellence in Graduate Polymer Research Award from the American Chemical Society, Best PhD Thesis Award from Sigma Xi, and Postdoctoral Fellow Research & Education Award from Johns Hopkins University.