Optical and Atomic Force Microscopy Study of Non-covalently functionalized CVD Graphene

by Omolewu, Abayomi; Shi, Guangyi; Tian, Z. Ryan; Meng, Xiangbo; Wejitwa, Uchcchukwu

Chemical functionalization is a method that is being explored to take advantage of the intriguing properties of graphene and its derivatives. Surfactant treatments have been successfully employed to non-covalently functionalize graphitic materials such as carbon nanotube and graphite. However, there is still need to investigate the surfactant treatment approach for commercially available chemical vapor deposited (CVD) graphene on silicon-silicon dioxide substrate. CVD graphene is one of the large-scale graphene available; hence, it is essential to understand how surfactants interact with it. This work presents the optical and atomic force microscopy study of non-covalently-functionalized graphene using Sodium Dodecyl Sulphate. CVD graphene on silicon/silicon dioxide (Si/SiO2) substrates were treated with different surfactant concentrations for different times. Unlike other derivatives of graphene, like carbon nanotube and graphite where the delamination of graphene sheet from the substrate is not a major concern, results show that the stability of the CVD graphene on the substrate is highly dependent on the concentration of the surfactant used for modifying the surface of the graphene, and the duration of treatment. Higher concentration of surfactant treatment was achieved by dissolving the surfactant with water and isopropyl alcohol. The result also suggests that different concentrations of surfactant affect the surface roughness of the functionalized graphene.

IEEE International Conference on Nano/Micro Engineered and Molecular Systems (IEEE - NEMS), 2019 14th