Biography: Prof. Jong Hak Kim received his Ph.D. degree in Chemical Engineering department of Yonsei University, South Korea in 2003. He worked as a postdoctoral researcher in the department of materials science and engineering at Massachusetts Institute of Technology (MIT) until he joined Yonsei University in 2005 as an assistant professor. He is now a full professor of Chemical and Biomolecular Engineering department in Yonsei University. His current research interests include the design and synthesis of graft copolymers and their applications to gas separation membranes and polymer electrolyte for electrochemical devices. He has a publication record of over 270 papers in refereed international journals such as Adv. Mater., Adv. Funct. Mater., ChemSusChem, ACS Appl. Mater. Interfaces, J. Membr. Sci., Chem. Eng. J. and etc. The sum of the times cited is 5785 and h-index is 48.
Title of Speech: Solid Supercapacitor Based on Graft Copolymer Electrolyte
Abstract: Supercapacitors have attracted considerable interest for their applications in portable electronics, electric vehicles, and smart grids owing to their high power density, superior rate capability, and cycling stability. In particular, solid electrolytes with high safety, good flexibility, and wide potential windows have attracted significant interest as alternatives to conventional liquid electrolytes, which have the disadvantages of flammability and leakage. Poly(ethylene oxide) (PEO) has been widely used as a polymer matrix for immobilizing ionic liquids because of the flexible ethoxy groups and strong electron-donating ether oxygen. However, the highly crystalline PEO hinders ion transport due to limited chain mobility, which decreases ionic conductivity. Attempts have been made to reduce the crystallinity of PEO by incorporating ionic liquids and increasing the ionic conductivity of polymer electrolytes. However, there is still a need to prepare high-performance solid electrolytes that overcome the trade-off relationship between ionic conductivity and mechanical strength. In this conference, I will give a talk about high-performance polymer electrolytes based on graft copolymer, focusing on self-assembled ionic channel, which can improve ionic conductivity without losing the mechanical properties of the polymer. I will introduce a variety of graft copolymer such as poly(isobornyl methacrylate)-co-poly(ethylene glycol) methyl ether methacrylate and poly(2,2,2-trifluoroethyl methacrylate)-co-poly(ethylene glycol) behenyl ether methacrylate electrolytes, with emphasis on their nanostructure, morphology, interactions and electrochemical properties.
Biography: Dr. Kazuo Umemura is a full professor of Tokyo University of Science. His specialty is biophysics, especially, nanobioscience and nanobiotechnology. One of his recent interests is nanoscopic research of hybrids of biomolecules and carbon nanotubes (CNTs). Unique structures and physical/chemical properties of the hybrids are promising in biological applications such as nanobiosensors and drug delivery. Dr. Umemura received his B.S. degree in Physics from Nagoya University. His M.S. and Ph.D. degrees were given from Tokyo Institute of Technology. After working at several institutes/universities as a researcher in Japan and in China, he became a professor of Tokyo University of Science. Kagurazaka campus of Tokyo University of Science is located at the center of Tokyo, so five subway/railway lines reach in front of the campus.
Title of Speech: Microbiodevices Using Frustules with Single-Walled Carbon Nanotubes or Papain Enzyme
Abstract: Micron size bio devices are advantageous to maximize abilities of biomolecules such as enzyme proteins. When enzyme molecules are used for biochemical reactions with some substrates, of course good enzyme activity is obtained. However, recovery of enzymes from substrates/products after the enzyme reactions is not easy because separation of enzyme molecules from products and substrates. However, when enzyme molecules were bound on silica beads or glass beads, recovery of the enzymes by simple centrifugation is available. Furthermore, it is known stability of enzyme molecules could be improved by attaching the enzymes on micron beads. In this work, we demonstrated fabrication of the frustule biodevices with single-walled carbon nanotubes (SWNTs) or papain enzyme. Frustule is a shell of diatoms which are major photosynthetic planktons. Because specific density of frustules is much smaller than that of usual micron beads, our microbiodevices were floatable even without stirring. By this approach, we firstly fabricated a redox sensor using photoluminescence of SWNTs that were attached on frustule surfaces. Secondly, we established reusable papain devices with frustules. Our results revealed merits of the use of the nanoporous frustules for fabricating effective microbiodevices.