Covalent Immobilization of Graphene on Patterned SAMs for Investigation of Frictional Properties
Graphene, a two-dimensional sp2-hybridized carbon material, is a promising solid lubricant for sliding interfaces due to its high mechanical strength. The frictional properties of graphene depend on its interactions with the underlying substrate. This study explores the impact of van der Waals adhesion vs. covalent binding interactions between graphene and the supporting surface. This is done utilizing a mixed self-assembled monolayer (SAM) of octadecyltrichlorosilane (OTS) and a perfluorophenyl azide (PFPA) templated through particle lithography. Single-layer graphene was mechanically exfoliated on the patterned SAMs and was identified by a combination of Raman microspectroscopy and atomic force microscopy. Friction force microscopy was used to investigate the frictional properties of the composite surface. Preliminary results showed that graphene overlaid on the patterned SAMs had lower friction than exposed OTS or PFPA, however, there was no discernible difference between the covalently bound and the van der Waals adhered graphene under low loads (1 nN).
Keywords: self-assembly, surface chemistry, tribology, graphene, friction
Topic(s):Chemistry
Presentation Type: Oral Paper
Session: 204-1
Location: MG 1098
Time: 9:45