▎ 摘　　要

The electric-carrying nanofriction properties of graphene are vitally important in the reliability and lifetime of graphene-based micro-/nanoelectromechanical systems. However, ubiquitous atomic-scale steps on graphene have an impact on their friction properties. In this work, electric-carrying nanofriction properties of atomic-scale steps on graphene were studied using the conductive atomic force microscope. Lateral force at uncovered step increased noticeably with the increasing voltages. Electrostatic interaction between the tip and dangling bonds along the step edges significantly increases the lateral force. In contrast, the lateral force of covered steps has only a slight increase as the voltage increases. In addition, oxidation of graphene is more likely to occur at uncovered step due to water molecules adsorbed by dangling bonds. The observations provide a deeper insight into the frictional behavior of atomic-scale steps on graphene.