Combining Low Energy Electron Microscopy and Thermal Raman Spectroscopy for Graphene Analysis

0568495 - ÚPT 2023 RIV CZ eng A - Abstrakt
Průcha, Lukáš - Lejeune, M. - Kizovský, Martin - Materna Mikmeková, Eliška
Combining Low Energy Electron Microscopy and Thermal Raman Spectroscopy for Graphene Analysis.
16th Multinational Congress on Microscopy, 16MCM, 04-09 September 2022, Brno, Czech Republic. Book of abstracts. Brno: Czechoslovak Microscopy Society, 2022 - (Krzyžánek, V.; Hrubanová, K.; Hozák, P.; Müllerová, I.; Šlouf, M.). s. 166-167. ISBN 978-80-11-02253-2.
[Multinational Congress on Microscopy /16./. 04.09.2022-09.09.2022, Brno]
Grant CEP: GA TA ČR(CZ) TN01000008
Institucionální podpora: RVO:68081731
Klíčová slova: graphene * SLEEM * Raman Spectroscopy
Obor OECD: Electrical and electronic engineering
https://www.16mcm.cz/wp-content/uploads/2022/09/16MCM-abstract-book.pdf

Graphene as a very promising material for the semiconductor and battery industry has its indisputable advantages. Though it has been discovered almost two decades ago, we still have
some gaps in knowledge regarding its behavior during temperature changes on different surfaces, even though it is critical for its use in practice. Electron microscopy, and specifically Scanning Low Energy Electron Microscopy (SLEEM), is a very useful analyzing tool for graphene but it is not used very often. Its advantages are not only counting the number of graphene layers and low interaction volume but also because low energy electrons can clean the surface from the hydrocarbons adsorbed from the atmosphere which is necessary specifically for studying 2D materials. On the other hand, Raman spectroscopy is one of the most common tools how to analyze this 2D material very quickly and precisely since the main peaks (2D, G, and D) in the spectra can very precisely tell much useful information about graphene, from the number of layers to lattice disorders. These two analyzing methods together create a powerful duo for analyzing graphene that can be hardly replaceable. Our created graphene is thus analyzed not only by Raman microscope but also by confocal microscope and electron microscope. In this study, we focused on graphene behavior under a very wide range of temperatures ranging from -190 to 600 °C measured during one sitting with the Raman microscope. Our CVD-grown graphene was placed onto different sample surfaces to study how the different thermal expansions affect graphene. In the past, some studies focused mainly on the graphene on the SiO2 surfaces with a lesser range of temperatures but here we added to SiO2 also platinum, gold, and copper. From the Raman spectra, we calculated the Raman spectra thermal shift for all the different substrates. We also studied the thermal disintegration of carbon bonds in graphene not only through the rising D peak but also from the change in the changes in the whole spectrum. From the obtained data, we also proposed the possible temperature for each substrate at which the graphene irreversibly changes its form and thus is destroyed.
Trvalý link: https://hdl.handle.net/11104/0339795