title: Friction and Wear Properties of Different Types of Graphene Nanosheets as Effective Solid Lubricants.
abstract: Friction and wear properties of graphene nanosheets prepared by different processes as solid lubricant on silicon dioxide have been comparatively studied via calibrated atomic force microscopy. The effects of normal load, humidity, and velocity on the friction were also investigated. All kinds of graphene nanosheets possess friction-reduction properties on the nanoscale. Mechanically exfoliated graphene nanosheets exhibit ultralubrication and zero wear under high pressure due to perfect graphitic structure and a hydrophobic surface. Defects in chemical vapor deposited graphene nanosheets decrease the antiwear and friction-reduction capability. The graphene oxide nanosheets (GOS) show the weakest friction-reduction properties on account of destroyed graphitic structure and a hydrophilic surface. The reduced graphene oxide nanosheets (RGOS) possess better friction reduction than GOS by virtue of hydrophobic surface properties. Both RGOS and GOS have weak antiwear properties due to the destroyed graphitic structure. Antiwear properties are correlated strongly with the structure, and friction depends mainly on the structure and surface properties.
authors.affiliation: †College of Mechanical Engineering, Donghua University, Shanghai 201620, China.
authors.forename: Yitian
authors.initials: Y
authors.lastname: Peng
authors.affiliation: ‡School of Mechanical Engineering, Southeast University, Nanjing 211189, China.
authors.forename: Zhuoqiong
authors.initials: Z
authors.lastname: Wang
authors.affiliation: †College of Mechanical Engineering, Donghua University, Shanghai 201620, China.
authors.forename: Kun
authors.initials: K
authors.lastname: Zou