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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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Reactive events at the graphene oxide–water interface
Graphene oxide exhibits interesting reactive events at its interface with water, with water as an active participant. The reactive events are influenced by the level of oxidation of the graphene oxide sheet. The fully oxidized sheet tends to make the interfacial water media acidic leaving the sheet negatively charged, whereas the reduced sheet can form comparatively long lived carbocations as well as split water forming two alcohol groups on the sheet.
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- Award ID(s):
- 1845795
- PAR ID:
- 10324556
- Date Published:
- Journal Name:
- Chemical Communications
- Volume:
- 57
- Issue:
- 88
- ISSN:
- 1359-7345
- Page Range / eLocation ID:
- 11697 to 11700
- 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
- Journal Article:
- https://doi.org/10.1039/D1CC04589J
