Department of Chemistry Seminar Announcement

1. Department of Chemistry Seminar Announcement About the Speaker Abstract Prof. Xi Zhang earned his Ph.D. (1992) in the field of polymer chemistry and physics under the joint-supervision of Prof. Jiacong Shen, Jilin University and Prof. Helmut Ringsdorf, University of Mainz, Germany. He worked at Key Lab of Supramolecular Structure and Materials, Jilin University as a lecturer and then full professor from 1992 to 2004. Since 2004, he is a full professor of the Department of Chemistry, Tsinghua University, Beijing. He is senior editor of Langmuir and has served as Editorial Board Members of several journals, including Chemical Communications. In 2007, he was selected as a member of Chinese Academy of Sciences. In 2008, he was selected as fellow of Royal Society of Chemistry, UK. Since 2010, he is vice president of Chinese Chemical Society. His research interests are focused on supramolecular assembly, polymer thin films, and single-molecular force spectroscopy of polymers. Superamphiphiles are amphiphiles that are formed by non-covalent interactions. It can be driven by single noncovalent interaction including host-guest interactions, hydrogen bonds, and charge transfer interactions or combined interaction of different noncovalent forces.[1] The superamphiphiles can be low-molecule-weight as well as polymers. In contrast to conventional amphiphiles, superamphiphiles are synthesized by noncovalent bonds, thus reducing the needs of chemical synthesis. Generally, using the concept of supramolecular engineering, we can fabricate superamphiphile with various topologies. The topologies of superamphiphiles include bola-form, Gemini form, H-form, X-form, etc, which also exist in conventional amphiphiles. Moreover, some topologies, such as rotaxane-form, which doesn’t exist in conventional amphiphiles, can also be realized in superamphiphiles. One of the advantages of superamphiphiles is that functional groups, such as stimuli-responsive moieties, can be attached to the superamphiphiles on the basis of noncovalent interactions. Therefore, superamphiphiles are easy to be functionalized. As a result, superamphiphiles are a new type of building blocks that are able to fabricate “smart” self-assembling nanostructures, such as pH-responsive nanofibers, photo-responsive nanocontainers, enzyme-responsive drug delivery cargoes. In summary, if the formation of superamphiphiles is regarded as a first-order self-assembly, it is probable that superamphiphiles can function as building blocks for constructing highly-ordered assemblies by so-called second-order self-assembly. The advance of superamphiphiles will not only enrich the family of conventional amphiphiles that are formed based on covalent bonds, but will also provide a new bridge between the colloidal and supramolecular sciences. In addition, it provides a new avenue for the assembly of functional supramolecular materials. Key words: superamphiphiles, supramolecular engineering, hierarchical self-assembly, functional supramolecular nanostructures All are Welcome