报告人简介： 

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跟随周武博士与Sokrates Pantelides教授进行新型二维材料的结构与性能研究，并广泛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，在Nature Nanotechnology，Nature Materials，Nano Letters等高影响力期刊上发表多项研究成果。2015年底博士毕业后赴日本继续进行扫描透射电镜研究。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教授指导下继续进行低电压球差校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和结合高能量和空间分辨率下单原子尺度的电子能量损失谱特性。  

报告摘要： 

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. Intrinsic defects, such as vacancies, dislocations and boundaries, are known to have profound influence on the electronic and optical properties of these materials. In order to fully develop the potential of monolayer materials, it is useful to recognize and understand the dynamical behavior of structural defects inside the monolayers matrix. In this talk I will show the atomic resolution characterizations of various defects in 2D monolayer materials and their effect to the properties of the materials using the combination of scanning transmission electron microscopy (STEM) and density functional theory (DFT). Moreover, I will also show that the evolution of defects in TMDC monolayers not only can be directly monitored and explained at the atomic scale, but can also be utilized to create new nanostructures with desired properties.