双片二硫化钼纳米薄片的电子衍射分析

Electron diffraction analysis of MoS_2 double nano-sheets

本文使用高分辨透射电子显微和电子衍射方法研究二硫化钼二维纳米材料薄片的微观结构。实验记录了样品在不同倾转角度下的衍射图,分析确认了衍射图中的一些衍射斑点随倾转角度加大而出现分裂的现象。本文通过一个空间几何模型来解释衍射图中衍射斑点分裂现象的成因,认为样品中含有两片互相之间有一定夹角的二硫化钼纳米薄片。两个二维纳米薄片分别对应分裂衍射斑点中的一组。经过模拟计算,得出这两片二硫化钼纳米薄片的夹二面角为156.6°(23.4°)。本文中的实验和模拟方法可以推广到对其它二维纳米材料薄片取向和相对空间方位的计算。

This paper presents an experimental method,a geometric model,and an analytic procedure for understanding and calculating the dihedral angle between two inclined two-dimensional molybdenum disulfide（MoS2） nano-sheets. The experimental method includes taking electron diffraction patterns at different tilt angles and measuring the fine structure of each set of split diffraction spots. The measured data were taken into simulations to calculate the dihedral angles between the nano-sheets and the Ewald plane.These dihedral angles were used in a geometric model to obtain the dihedral angle between the two MoS2 nano-sheets. It was determined that the dihedral angle between two MoS2 nano-sheets was 156. 6°（ 23. 4°）. The method described in this work is useful for and can be extended to solving geometric relationships between other two-dimensional nanomaterials.