摘要
在许多恶劣的工作环境中,器件难免会曝露在电子束辐照下.对于单原子层厚度的二维材料而言,电子束辐照经常会造成其本征性能的衰减.如何避开这一影响对于多功能化的二维异质结器件来讲至关重要.然而,电子束辐照对于二维异质结的影响至今仍缺乏充分深入的研究.本工作发现利用异质结的堆垛可以阻碍单层二硫化钼(MoS_2)由于电子束辐照带来的性能衰退.通过在MoS_2与基底之间插入单层石墨烯,在同样剂量的电子束辐照轰击下,异质结区域的光致发光强度始终大于纯单层MoS_2;而且与纯单层区域明显的发光能量变化相比,MoS_2/石墨烯异质结区域的发光能量具有更佳的稳定性.这一现象归因于石墨烯的阻隔效应:由于单层石墨烯的存在抑制了基板对MoS_2的影响.此外,我们也系统地揭示了电子束辐照对MoS_2/石墨烯异质结拉曼光谱及电学传输特性的影响.本工作不仅有助于加深人们对二维异质结辐照效应的认知,同时也为新型抗辐射器件的设计开辟了新的途径.
Two-dimensional （2D） materials have attracted growing attention since the discovery of graphene [1]. Transition metal dichalcogenide （TMD） semiconductors, such as MoS2 and WS2, became popular materials in recent years, because they usually have intrinsic bandgaps and an in- direct-to-direct bandgap transition from bulk to mono- layer limit [2-6]. Although graphene and TMDs are promising materials in field-effect devices [7-9], their heterostructures are more advanced in charge-splitting functions for the applications in optoelectronic devices [10-15].
作者
洪聖哲
傅德颐
侯纪伟
周段亮
王博伦
孙雨飞
柳鹏
刘锴
Shengzhe Hong;Deyi Fu;Jiwei Hou;Duanliang Zhou;Bolun Wang;Yufei Sun;Peng Liu;Kai Liu(State Key Laboratory of New Ceramics and Fine Processing,School of Materials Science and Engineering,Tsinghua University,Beijing 100084,China;Department of Physics,National University of Singapore,2 Science Drive 3,Singapore 117551,Singapore;Department of Physics and Tsinghua-Foxconn Nanotechnology Research Center,Tsinghua University,Beijing 100084,China)
基金
supported by the National Natural Science Foundation of China (11774191, 51727805, and 51672152)
the Open Research Fund Program of the State Key Laboratory of LowDimensional Quantum Physics (KF201603)
the Thousand Youth Talents Program of China
