Garcia Alejandra, Raya Andres M, Mariscal Marcelo M, Esparza Rodrigo, Herrera Miriam, Molina Sergio I, Scavello Giovanni, Galindo Pedro L, Jose-Yacaman Miguel, Ponce Arturo
Department of Physics and Astronomy, University of Texas at San Antonio, One UTSA Circle, San Antonio, TX 78249, USA.
Departamento de Ciencia de los Materiales en Ingeniería Metalúrgica y Química Inorgánica, Universidad de Cádiz, 11510 Puerto Real, Cádiz, Spain.
Ultramicroscopy. 2014 Nov;146:33-8. doi: 10.1016/j.ultramic.2014.05.004. Epub 2014 Jun 2.
In this work we examined MoS₂ sheets by aberration-corrected scanning transmission electron microscopy (STEM) at three different energies: 80, 120 and 200 kV. Structural damage of the MoS₂ sheets has been controlled at 80 kV according a theoretical calculation based on the inelastic scattering of the electrons involved in the interaction electron-matter. The threshold energy for the MoS₂ material has been found and experimentally verified in the microscope. At energies higher than the energy threshold we show surface and edge defects produced by the electron beam irradiation. Quantitative analysis at atomic level in the images obtained at 80 kV has been performed using the experimental images and via STEM simulations using SICSTEM software to determine the exact number of MoS2₂ layers.
在这项工作中，我们通过像差校正扫描透射电子显微镜（STEM）在80、120和200 kV这三种不同能量下对二硫化钼薄片进行了研究。根据基于电子与物质相互作用中电子非弹性散射的理论计算，在80 kV时二硫化钼薄片的结构损伤得到了控制。已在显微镜中找到并通过实验验证了二硫化钼材料的阈值能量。在高于能量阈值的能量下，我们展示了电子束辐照产生的表面和边缘缺陷。使用实验图像并通过SICSTEM软件进行STEM模拟，对在80 kV下获得的图像进行了原子水平的定量分析，以确定二硫化钼层的确切数量。
