Dresden 2020 – wissenschaftliches Programm
Die DPG-Frühjahrstagung in Dresden musste abgesagt werden! Lesen Sie mehr ...
CPP 6.1: Vortrag
Montag, 16. März 2020, 11:30–11:45, ZEU 255
Voltage-dependent quantitative analysis of electron-dose-limited resolution for imaging two-dimensional covalent organic framework — •Baokun Liang1, Haoyuan Qi1,2, Hafees Sahabudeen2, Xinliang Feng2, and Ute Kaiser1 — 1Central facility for Electron Microscopy, Group of Electron Microscopy of Materials Science, University of Ulm, 89081 Ulm, Germany — 2Department of Chemistry and Food Chemistry & Center of Advancing Electronics Dresden, Dresden University of Technology, 01062 Dresden, Germany
Two-dimensional covalent organic framework (2D COF) are promising candidates for organic electronics and next-generation energy storage. However, due to electron irradiation damage, high resolution (HR) TEM imaging of 2D COFs remains challenging, posing a substantial limitation on the structural elucidation of these organic 2D materials. Therefore, it is necessary to unravel the correlation between total electron dose and achievable specimen resolution for specific specimens. To investigate the relationship between total electron dose and achievable specimen resolution, we performed a dose-series analysis with 2D COF in electron diffraction mode under different acceleration voltages (300, 200, 120, 80 kV). With accumulating electron dose, the higher-order reflections gradually vanish, representing the degradation of specimen resolution. For quantitative analysis, the intensity of reflections within a specific resolution band was analyzed. Our method offers a quick and straightforward determination of dose-related specimen resolution under different voltages. These results lay the foundation for the HRTEM imaging of beam sensitive 2D COFs.