清洁能源实验室学术报告（五） 2011-4-20

报告时间： 2011年4月20日（星期三）下午 2：30 – 3：30

报告题目：Single-Molecule Interfacial Electron Transfer-Dynamics in Solar Energy Conversion and Photocatalysis

报告人： Prof. H. Peter Lu Bowling Green State University, USA

报告人简介：
Prof. H. Peter Lu got his B.S. and M.S. from Peking University in 1982 and 1984. He got his M. Sci and Ph. D. from Columbia University in 1987 and 1991. From 1991 to 1995, he was a research associate in Department of Chemistry, Northwestern University. From 1995 to 2006, he worked in Pacific Northwestern National Laboratory as a postdoctoral fellow, a senior research scientist and chief scientist, respectively. Since 2006, he has been an Ohio Eminent Scholar and Professor of Chemistry in Bowling Green State University. His research interest focuses on single-molecule spectroscopy studies of molecular kinetics and dynamics in condensed phase and at interfaces. He is the author or co-author of more than 50 scientific publications including Nature, Phys. Rev. Lett., J. Am. Chem. Soc., Appl. Phys. Lett. and so on.

报告简介：
In this talk, Prof. Lu will focus on interfacial electron transfer occurred in solar energy conversion and photocatalysis. Extensive ensemble averaged studies have indicated inhomogeneous and complex dynamics of interfacial ET reaction. To characterize the inhomogeneity and the complex mechanism, we have applied single-molecule spectroscopy and correlated AFM/STM imaging to study the interfacial ET dynamics of dye molecules adsorbed at the surface of TiO2 nanoparticles. We have studied the complex interfacial ET dynamics by using a combined spectroscopic approach of single molecule spectroscopy, near-field spectroscopy, Raman spectroscopy, and femtosecond transient pump-probe absorption spectroscopy, observing intermittent single-molecule interfacial electron transfer dynamics. We have demonstrated an imaging analysis of single surface states and associated interfacial charge transfer coupling on the TiO2 crystal surface using tip-enhanced near-field topographic-spectroscopic imaging analyses. The imaging and characterization of the surface states and their distributions on TiO2 surfaces at nanoscale are critically relevant to a deep understanding of interfacial electron transfer dynamics and energetics critical to solar energy conversion and photocatalysis. Furthermore, we have applied site-specific AFM-Raman spectroscopy on analyzing ET associated mode-specific vibrational reorganization energy barriers. Our experiments revealed site-to-site variations in the vibrational reorganization energy barriers in the interfacial ET systems. Our recent experiments on single-molecule spontaneous ground-state electron transfer fluctuation will also be discussed.