纳米标准与检测重点实验室第196期学术报告

报告题目：Selective self-assembly of 2,3-diaminophenazine molecules on MoSe2 mirror twin boundariese

报 告 人：Dr. Xiaoyue He，National University of Singapore

时    间：2018年10月17日 下午3: 00

地    点：南楼2层会议室

邀 请 人：裘晓辉 研究员

 报告摘要：

The control of the density and type of line defects on two-dimensional (2D) materials enable the development of new methods to tailor their physical and chemical properties. In particular, mirror twin boundaries (MTBs) on transition metal dichacogenides (TMDs) have attracted much interest due to their metallic state with charge density wave (CDW) transition and spin-charge separation property. In this work, we demonstrate the self-assembly of 2,3-diaminophenazine (DAP) molecule porous network with alternate L-type and T-type aggregated configurations on the MoSe₂ hexagonal wagon-wheel pattern surface. This site-specific molecular self-assembly is attributed to the more chemically reactive metallic MTBs compared to the pristine semiconducting MoSe₂ domains. First-principles calculations reveal that the active MTBs couple with amino groups in the DAP molecules facilitating the DAP assembly. Our results demonstrate the site-dependent electronic and chemical properties of MoSe₂ monolayers, which can be exploited as a natural template to create large-scale ordered nanostructures.

报告人简介：

2017-present   Research Fellow           National University of Singapore

2014-2017       Assistant professor      National Center for Nanoscience and Technology

2008-2014       Ph.D.                              Institute of Physics, Chinese Academy of Sciences                                      

2004-2008       B.S.                                Yunnan University

Her current research interests include the growth of two-dimensional transition metal dichalcogenides (TMDs), inverstigation of their intrinsic properties and the interface properties of organic-TMDs and various van der Waals(vdWs) heterostructures by using molecular beam epitaxy(MBE) combinied scanning tunneling microscopy(STM) and non-contact atomic microscopy(nc-AFM).