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Title: Interfacial layering of hydrocarbons on pristine graphite surfaces immersed in water
Interfacial water participates in a wide range of phenomena involving graphite, graphite-like and 2D material interfaces. Recently, several high-spatial resolution experiments have questioned the existence of hydration layers on graphite, graphite-like and 2D material surfaces. Here, 3D AFM was applied to follow in real-time and with atomic-scale depth resolution the evolution of graphite–water interfaces. Pristine graphite surfaces upon immersion in water showed the presence of several hydration layers separated by a distance of 0.3 nm. Those layers were short-lived. After several minutes, the interlayer distance increased to 0.45 nm. At longer immersion times (∼50 min) we observed the formation of a third layer. An interlayer distance of 0.45 nm characterizes the layering of predominantly alkane-like hydrocarbons. Molecular dynamics calculations supported the experimental observations. The replacement of water molecules by hydrocarbons on graphite is spontaneous. It happens whenever the graphite–water volume is exposed to air.  more » « less
Award ID(s):
1945589
NSF-PAR ID:
10398284
Author(s) / Creator(s):
; ; ;
Date Published:
Journal Name:
Nanoscale
Volume:
14
Issue:
38
ISSN:
2040-3364
Page Range / eLocation ID:
14178 to 14184
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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