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For this experimental study on evaporation of water from graphene, two graphene samples with different thickness and microstructure were used. Figure 1 shows the representative optical and scanning electron microscope (SEM) images of the two samples. Sample 1, shown in Figure 1a-b, is a 3 to 4 atomic layer of continuous graphene sheet grown on copper substrate via chemical vapor deposition (CVD) and was subsequently transferred to a quartz substrate using a wet chemical method reported previously [5]. The graphene thickness is at 1.2 nm to 1.4 nm, as measured by Atomic Force Microscopy. Sample 2, shown in Figure 1c-d, represents an inkjet-printed reduced graphene oxide on silicon and subsequently treated with a direct pulsed laser writing (DPLW) process for surface 3D-nanostructuring. The layer thickness is between 6 µm and 7 µm.
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Surface Characterization of Sodium Cholate Treated CVD Graphene;
The advancement of graphene has created a need in exploring its properties for different applications. One way to explore its properties is by reducing its hydrophobicity. To overcome hydrophobicity of graphene, surfactants have been used in functionalization, hence improving the surface properties of the graphene monolayer. Therefore, investigating surfactant treatment for CVD graphene becomes useful in understanding the surface property effects on graphene. This study utilizes CVD graphene on silicon substrates. Its treatment was done with varying concentrations of Sodium Cholate (SC) for different treatment times. These samples were then characterized using Atomic Force Microscopy (AFM) to investigate the surface properties of the samples before and after treatment. To be optimized, the graphene must remain attached to the silicon substrate. The result shows that the integrity of the graphene, which is basically the sp2 structure, is preserved as there was no delamination from the substrate even after treatment for as long as 2 hours in 1% weight/volume concentration of the SC solution.
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- Award ID(s):
- 2046167
- PAR ID:
- 10511076
- Publisher / Repository:
- IEEE
- Date Published:
- Journal Name:
- IEEE 23rd International Conference on Nanotechnology (IEEE-NANO 2023)
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.1109/NANO58406.2023.10231236
