Prof. Andrew Wee is a Professor of Physics at the National University of Singapore (NUS), and also Director of the Surface Science Laboratory. He is also NUS Vice President (University and Global Relations), and was previously Dean of Science (2007-14). Andrew is President of the Singapore National Academy of Science (SNAS). He was awarded the President’s medal in 2008 by the Institute of Physics Singapore (IPS), and is a Fellow of the Institute of Physics (IoP) UK, IPS and SNAS, as well as an academician of the Asia-Pacific Academy of Materials.
His research interests are in surface and nanoscale science, STM and synchrotron radiation studies of the molecule-substrate interface, graphene and related nanomaterials. He has published more than 400 internationally refereed scientific papers. He is an Associate Editor of ACS Nano since 2011, and serves or has served on several journal editorial boards including Applied Physics Letters-Journal of Applied Physics (2009-2011), Surface and Interface Analysis (2005-), and Surface Review and Letters (2002-).
Andrew was previously a visiting scientist with the Lawrence Berkeley National Laboratories, a Commonwealth Fellow as well as a Rhodes Scholar at the University of Oxford, where he received his DPhil. He holds a Bachelor of Arts (Honours) in Physics as well as a Masters degree from the University of Cambridge.
演讲题目：Graphene Nanoribbons and 2D Materials for Novel Device Applications
主题会场
开始时间2014-09-01 09:00:00
结束时间2014-09-01 17:00:00
内容摘要
1D graphene nanoribbons have tunable electronic bandgaps, thereby enabling graphene electronic/optoelectronic applications. We have demonstrated both bottom-up and top-down methods for fabricating graphene nanoribbons. First, we present surface-assisted bottom-up fabrication of atomically precise armchair graphene nanoribbons (AGNRs) with predefined widths, namely 7-, 14- and 21-AGNRs, on Ag (111) as well as their spatially resolved width-dependent electronic structures.[1] Second, we demonstrate the top-down fabrication of an intramolecular junction by the controllable unzipping of single-walled carbon nanotubes, combining a graphene nanoribbon and single-walled carbon nanotube in a 1D nanostructure.[2] This junction shows strong gate-dependent rectifying behavior, and we demonstrate the use of the junction in prototype directionally dependent field-effect transistors, logic gates and high performance photodetectors.
2D transition metal dichalcogenides (TMDs, e.g. MX2, M = Mo, W; X = S, Se, Te) are promising alternatives to graphene, as they can have a direct bandgap enabling electronic and optical applications. We use high resolution STM/STS to study the atomic structure and intrinsic electronic properties of MoS2 layers (mono-, bi-, tri-) directly deposited on HOPG substrates by CVD.[3] We also investigate highly crystalline and large-area tungsten diselenide (WSe2) monolayers on sapphire grown by CVD.[4] The monolayer films display strong photoluminescence, opening up potential applications in optoelectronics. We fabricate monolayer WSe2 transistors with ON/OFF current ratio of up to 109, and mobility larger than 7.3cm2/Vs.
官方微信订阅号
京公网安备 11010802023402号