时间: 12月23日星期五上午10:00 -11:00
地点: 教十一电镜中心318室
邀请人: 金传洪
Revealing the structural dynamics and electronic properties of defects in 2D materials atom-by-atom
Junhao Lin (林君浩)
National Institute of Advanced Industrial Science and Technology (AIST), AIST Central 5, Tsukuba 305-8565, Japan
Two-dimensional materials, including graphene, hexagonal boron nitride and transition-metal dichalcogenide (TMDC) monolayers, are promising atom-thin candidates for flexible nanoelectronic and optoelectronic applications. In order to fully develop the potential of monolayer materials, it is essential to understand the atomic structures and dynamical behaviors of intrinsic defects and their related electronic properties, which are known to have profound influence on the performance of the parent materials. In the first half of the talk, I will briefly show the atomic scale characterizations of complex defect structures in air-stable 2D materials, such as MoS2 and MoSe2, and their atom-by-atom structural evolutions as monitored by sequential Z-contrast scanning transmission electron microscopy (STEM) imaging [1-5]. In the second half of the talk, I will discuss our recent results on in-situ characterizations of structural dynamics and single atom spectroscopy of defects in the emerging novel 2D materials, such as monolayer of air-sensitive telluride, amorphous carbon and noble metal dichalcogenide.
Bio:
林君浩，1986年生，美国田纳西州Vanderbilt大学物理学博士。博士期间在美国橡树岭国家实验室师从周武博士与Sokrates Pantelides教授进行新兴二维材料的结构与性能研究，广泛结合使用高分辨扫描透射电镜和第一性泛函原理计算作为主要研究工具，以第一作者或共同第一作者在Nature Nanotechnology，Nature Materials，Nano Letters等高影响期刊发表重要研究成果。2015年底博士毕业后赴日本继续进行低电压原位扫描透射电镜的博士后研究工作。现任日本学术振兴会研究员（JSPS fellow），在日本国立产业综合研究所Kazu Suenaga教授指导下进行球差纠正扫描透射电镜在二维材料上的应用研究，主要研究方向包括高低温下原子尺度物相变化的原位表征，结合高能量和空间分辨率下单原子尺度的电子损失光谱特性，以及利用低温低电压低辐照剂量来探索对电子辐照敏感的二维和钙钛矿材料。
