• 文献标题:   Friction and Adhesion of Different Structural Defects of Graphene
  • 文献类型:   Article
  • 作  者:   TRIPATHI M, AWAJA F, BIZAO RA, SIGNETTI S, IACOB E, PAOLICELLI G, VALERI S, DALTON A, PUGNO NM
  • 作者关键词:   afm, graphene, defect, friction, adhesion
  • 出版物名称:   ACS APPLIED MATERIALS INTERFACES
  • ISSN:   1944-8244
  • 通讯作者地址:   Univ Trento
  • 被引频次:   3
  • DOI:   10.1021/acsami.8b10294
  • 出版年:   2018

▎ 摘  要

Graphene structural defects, namely edges, step-edges, and wrinkles, are susceptible to severe mechanical deformation and stresses under tribo-mechanical operations. Applied forces may cause deformation by folding, buckling, bending, and tearing of these defective sites of graphene, which lead to a remarkable decline in normal and friction load bearing capacity. In this work, we experimentally quantified the maximum sustainable normal and friction forces, corresponding to the damage thresholds of the different investigated defects as well as their pull-out (adhesion) forces. Horizontal wrinkles (with respect to the basal plane, i.e., folded) sustained the highest normal load, up to 317 nN, during sliding, whereas for vertical (i.e., standing) wrinkles, step-edges, and edges, the load bearing capacities are up to 113, 74, and 63 nN, respectively. The related deformation mechanisms were also experimentally investigated by varying the normal load up to the initiation of the damage from the defects and extended with the numerical results from molecular dynamics and finite element method simulations.