报告题目：Towards Practical SERS Sensing
报 告 人：Prof. Yiping Zhao (University of Georgia, USA)
报告摘要：Since its discovery more than 30 years ago, the surface enhanced Raman scattering (SERS) has been recognized as a high sensitive detection technique for chemical and biological sensing and medical diagnostics. However, the practical application of the remarkable analytical sensitivity of SERS has not been widely accepted as a viable diagnostic technique due to the difficulty in preparing robust and reproducible substrates of the correct surface morphology that provide maximum SERS enhancements. Recently, we demonstrate that the aligned silver nanorod (AgNR) array substrates engineered by the oblique angle deposition method are capable of providing extremely high SERS enhancement factors (>108). The enhancement factor depends strongly on the length of the Ag nanorods, the substrate coating, the polarization of the excitation light, as well as the incident angle. With the optimized AgNR SERS substrates, we also show that SERS is able to detect trace amount of virus, bacteria, microRNAs, or other chemical and biological molecules, and distinguish different viruses/bacteria and virus/bacteria strains, suggesting that this technology can be applied to detect genetically modified viruses that may be agents of bioterrorism. The substrate can be tailored into multi-well chip for high throughput screening of chemical/biological specimen, integrated into fiber tip for portable sensing, incorporated into fluid cells or microfluidic devices for in situ real-time monitoring dynamic process, or fabricated onto a flexible substrate for tracking and identification. All these development has demonstrated that AgNR SERS substrates could play an important role for practical sensing applications in future defense and security.
报告人简介：Dr. Yiping Zhao received his B.S. degree in Electronics from Peking University in 1991， and MS degree in condensed matter physics from Institute of Semiconductors, Chinese Academy of Sciences in 1994. He completed his Ph.D. degree in Physics at Rensselaer Polytechnic Institute in 1999. He is currently a full Professor at the Department of Physics and Astronomy in University of Georgia. Prof. Zhao is the author or co-author of 180 peer reviewed journal papers, 1 book, 4 book chapters, and 9 US patents. He has received the 2009 UGA Creative Research Medal, 1999 American Vacuum Society Graduate Student Award, and 1998 Materials Research Society Graduate Student Silver Medal Award. His major research interests are nanostructures and thin films fabrication and characterization, chemical and biological sensors, hydrogen storage materials, novel photocatalysts, biomaterials, and nanomotors.