TITLE: Responsive Nanostructured Optical Materials
SPEAKER: Prof. Yadong Yin, Department of Chemistry, University of California, Riverside
TIME:July 24 (Friday) PM13:30
LOCATION: Fifth-floor Lecture Hall, Chemistry Building A (化学A楼演讲厅)
INVITER: Prof. Shun-ai Che (车顺爱教授)

Abstract
Nanostructured materials with optical properties responsive to external stimuli are gaining increasing interests due to their intrigue potential applications in printing, sensing, signage, security documents, displays, and other color related devices. In this presentation, I will first discuss our recent progresses on the development of chemical approaches for the fabrication of various nanostructured materials whose optical properties can be dynamically tuned by controlling the spatial arrangement of the nanoscale building blocks. We also show that many novel optical materials could be developed by manipulating the diffraction, refraction, birefringence, and electronic resonances such as surface plasmon through controlling the interaction between light and the nanostructures of dielectric and metallic materials.  

My discussion will then be focused on our very recent development of a new color switching system based on reversible redox reactions that could be initiated by photocatalytic response of TiO2 nanocrystals. With the assistance of TiO2-based photocatalysts, UV light irradiation can effectively reduce the redox dyes and result in rapid color change, while recoloration can be achieved by re-oxidizing the system with the assistance of visible light irradiation or heating. The excellent performance of the new color switching system promises their potential applications as attractive rewritable media to meet our society’s increasing needs for sustainability and environmental conservation.

Biography
Prof. Yadong Yin received his B.S. (1996) and M.S. (1998) in Chemistry from the University of Science and Technology of China. From 1999 to 2002, he was a graduate student in the Department of Materials Science and Engineering at the University of Washington, Seattle, under the guidance of Prof. Younan Xia. In 2003, he became a postdoctoral fellow at Prof. Paul Alivisatos’ group at the University of California, Berkeley. Soon he joined the Molecular Foundry at the Lawrence Berkeley National Laboratory, as initially a postdoctoral fellow and then a staff scientist. Since 2006, he has been a faculty member at the Department of Chemistry, University of California, Riverside. His research interest focuses on the synthesis, self-assembly, and functionalization of nanostructured materials for catalytic, analytical, and photonic applications. Prof. Yin has received a number of national awards, including Cottrell Scholar Award from the Research Corporation for Science Advancement, DuPont Young Professor Grant, 3M Nontenured Faculty Grant, the Faculty Early Career Development (CAREER) award from the National Science Foundation, and the Distinguished Junior Faculty Award from the Chinese-American Chemistry Professor Association. He is currently an associate editor of the Journal of Materials Chemistry C, and also serves on the editorial board for NPG Asia Materials, Advanced Functional Materials, SCIENCE CHINA Materials, and ChemNanoMat.