Substrate-regulated nanoscale friction of graphene

In the present study, nanotribological measurements were performed via atomic force microscopy on Si/SiO2-supported graphene monolayers with varying oxide layer thicknesses. The observations uncovered significant discrepancies in resulting friction forces between each graphene sample. Nanoscale interfacial friction forces were observed to increase from ∼0.49 nN to ∼1.00 nN when the oxide layer thickness was increased from 90 nm to 300 nm. The findings were determined to be the result of increased phonon scattering which is responsible for the removal of the vibrational reduction of nanoscale friction. Such discrepancies in friction forces points toward the potential tunability of nanoscale friction in supported graphene.