报 告 人：L. James Lee 教授（美国俄亥俄州立大学）
Graphenes have recently received a great deal of attention because of their extraordinary mechanical, electrical and thermal properties. They can be achieved by the “bottom up” approach through epitaxial growth on the substrates via chemical vapor deposition or the “top down” approach from graphite by overcoming the van der Waals or π-orbital interactions between graphene nanosheets in graphite through liquid exfoliation, thermal shock, or chemically reduced pathways. The resulting graphene building blocks can then be assembled into functional thin films, coatings or other structures by the same van der Waals or π-orbital interactions. The weak non-covalent bonding among graphene nanosheets and between the graphene and the substrate, however, limits their industrial applications. Despite of one-decade research in this area, the construction of atomically bonded graphene networks, which are bridged at the edges of graphene nanosheets or linked via the graphene basal planes, remains a formidable challenge. We have recently discovered a simple and yet versatile method to atomically bind graphene nanosheets on a variety of solid substrates with unprecedented properties. This one-step approach can achieve high-strength carbide-bonded graphene coatings on both non-metallic and metallic substrates through vacuum-assisted thermal exfoliation of functional graphene nanopaper or low-cost Chemical Vapor Deposition (CVD) followed by thermal deposition of graphene sheets onto the substrate surfaces at elevated temperatures with the aid of silicon and silicone oxide radicals. The covalent carbide bonds are formed in-situ to bridge the graphene nanosheets as well as between the graphene and the substrate. The thickness of graphene coating ranging from nanometers to microns can be finely tuned by adjusting the loading content of graphene nanopaper and silicone rubber. We demonstrated the applicability of this new material and technology in advanced microscale polymer and glass molding, surface coating, and enhanced thermal management for high power electronics.
Dr. Lee is the Helen C. Kurtz Professor of Chemical and Biomolecular Engineering at The Ohio State University (OSU). He founded and serves as the Director of NSF Nanoscale Science and Engineering Center for Affordable Nanoengineering of Polymer Biomedical Devices (CANPBD) at OSU. He received a BS degree in chemical engineering from National Taiwan University and a Ph.D. degree in chemical engineering from University of Minnesota. Before joining OSU in 1982, he worked as a research scientist at General Tire and Rubber Company for 3 years. His research interest includes BioMEMS/NEMS, micro-/nanofabrication, and polymer and composite materials. He has more than 400 refereed journal publications, 30 patents and invention disclosures, and 14 book chapters. He was elected as the Fellow of Society of Plastics Engineers in 2001 and Fellow of American Institute for Medical and Biological Engineering in 2006. Dr. Lee received the 2008 Malcolm E. Pruitt Award from Council of Chemical Research, 2010 International Award from the Society of Plastic Engineers, and 2016 Lifetime Achievement Award, Society of Advanced Molding Technology.