国立新加坡大学专家报告

时间：2016年05月31日（周二）15:00-17:30

地点：物理馆323会议室

报告题目1：Plasmonic Metal-semiconductor Hybrid Photocatalystsfor Solar Energy Harvesting

报告简介：Efficient and extensive harvesting of solar energy is essential to resolving energy and environmental crises. Besides photovoltaics, photocatalysis is a potentially important means of harvesting solar energy. In photocatalysis, sunlight is absorbed by semiconductors to generate hot electrons and holes, subsequently they drive desirable uphill chemical reactions such as water splitting and CO2 conversion to useful hydrocarbons. The efficiency of semiconductor photocatalysts, however, is severely limited by their weak trapping power for sunlight. Au and Ag nanoparticles (NPs) exhibit strong localized surface plasmon resonance effect, leading to light trapping power much greater than semiconductor nanomaterials. Integrating plasmonic NPs with semiconductors has been proposed to significantly improve the efficiency of semiconductor photocatalysts. I will briefly review the fundamental physical and chemical processes important to the function of plasmonic hybrid photocatalysts, and address some key physical and material issues that need to be resolved in order to realize practical photocatalysts for large-scale applications.

报告人简介：Dr. WANG Xuesen is an associate professor at Department of Physics, National University of Singapore. He received BSc at Fudan University in China and PhD in physics at the University of Maryland in USA. His past research works are on atomic structure and morphology characterization, mostly using scanning tunnelling microscopy, of surfaces, thin films and nanostructures of various materials prepared in ultrahigh vacuum environment. He has published about 70 papers in scientific journals on these studies. His current research interest is mainly in metal-semiconductor hybrid nanostructures for catalysis and photocatalysis applications.

报告题目2：Nonlinear Optics with Advanced Materials

报告简介： Nonlinear optics was born in 1961, only one year after the laser invention. Since then, nonlinear optical phenomena have found a wide range of applications. To realize viable technological applications, materials with efficient nonlinear optical mechanisms are the key. Recent advances in two-dimensional materials (2DMs) and metal-organic frameworks (MOFs) have offered new types of materials. In this talk, we focus on their nonlinear optical responses when they are excited by processes of multiphoton absorption. As example [1, 2], we present our fundamental studies on two-photon absorption in graphene. In addition, we also present our observation of multiphoton absorption in 5-atomic-layer hexagonal Boron Nitride film [3]. Finally, we report both multiphoton-excited photoluminescence and third-harmonic generation from metal-organic frameworks [4, 5].

报告人简介：Dr. Wei Ji is Professor at Department of Physics, National University of Singapore. He was educated in China and the United Kingdom (BSc at Fudan University, Shanghai; and MSc and PhD at Heriot-Watt University, Edinburgh). His research focuses on novel materials for photonics and optoelectronics applications. His pioneering works in characterization and understanding of optoelectronic properties of various nanomaterials are well-recognized worldwide. He has published 240 papers in scientific journals listed in the ISI Web of Knowledge by Thomson Reuters, given more than 100 conference presentations, with 50 invited talks. Total citation of his papers is over 5000 with the h-index of 48. He is an Associate Editor for Optical Materials Express published by the Optical Society of America.

物理科学与技术学院

2016.5.30