▎ 摘　　要

Graphene as a well-known solid lubricant is widely used in micro-and nano-scale mechanical devices, decreasing the friction of graphene as far as possible is a perpetual task to improve the performance of these devices. A novel approach was proposed to decrease the friction of graphene against atomic force microscopy (AFM) tip by plasma treatment of the substrate. The plasma treatment of the substrate enhances the adhesive attraction between graphene and SiO2 substrate by generating stronger van der Waals attraction. Enhancing the adhesive attraction can indeed decrease the friction of graphene, regardless of the thickness of graphene and the kinds of AFM tip. Longer time of plasma treatment results in stronger adhesive attraction, leads to smaller friction. The decreased friction is mainly due to the combined action of the suppressed puckering of graphene and the reduced ability of graphene to adjust its atomic configuration. This novel approach will promote the engineering application of graphene and other related 2D materials as lubricants in MEMS/NEMS. (C) 2017 Published by Elsevier Ltd.