学术报告:Interface Engineering for WSe2 Based Optoelectronic Devices

发布者:金霞发布时间:2018-04-23浏览次数:62

人:陈伟 教授

报告题目:Interface Engineering for WSe2 Based Optoelectronic Devices

报告时间:2018423日下午午300

报告地点:能源与材料创新研究院215室

报告人简介:

   陈伟教授2001年在南京大学化学系获得学士学位,2004年新加坡国立大学化学系获得博士学位, 2009年初受聘为新加坡国立大学化学系和物理系助理教授,2013年获得终身制的副教授职位,2016年被聘为新加坡国立大学院长讲席教授, 2017年任化学系副系主任。

  陈伟教授目前主要关注于低维分子量子结构/二维材料的界面问题,及其在二维材料光电功能器件,有机光电功能器件,及纳米催化等方面的应用.在国际顶级期刊上已发表超过250篇论文,引用超过8800次,H-因子为49。陈伟教授于2006年新加坡李光耀研究员奖,2009年获得新加坡物理协会纳米技术奖,2010年获得日本日立公司日立研究员奖, 2010新加坡国立大学青年研究员奖,2012年新加坡青年科学家奖

报告简介:

Two dimensional (2D) atomic layered materials have been considered as promising building blocks for the next-generation electronic and optoelectronic devices due to their extraordinary and unique properties. The 2D atomic layered structure enables their immunity against the short channel effects, while the mechanical strength and structural flatness allow their integration into flexible and wearable circuits. In this talk, I will highlight our recent progress for interface engineering WSe2 based optoelectronics. (1) We report a direct observation of a controllable semiconductor-metal phase transition in bilayer WSe2 with K surface functionalization. Through the integration of in-situ field-effect-transistor (FET), X-ray photoelectron spectroscopy, ultraviolet photoelectron spectroscopy measurements and first-principles calculations, we identify that the electron doping from K adatoms drives bilayer WSe2 from a 2H-phase semiconductor to a 1T’-phase metal. (2) We report a multi-bit non-volatile optoelectronic memory based on a heterostructure of monolayer WSe2 and few-layer h-BN. The WSe2/BN memory exhibits a remarkable switching ratio of ~1.1×106, which ensures over 128 (7 bit) distinct storage states. The memory demonstrates outstanding robustness with retention time over ~4.5×104 s. Moreover, the ability of broadband spectrum distinction enables its application in filter-free color image sensor.