Dynamic electron transfer for reducing nanofriction of graphene at electrified interfaces

• Published in: Applied surface science 2020-08, Vol.520, p.146327, Article 146327
• Main Authors: Lang, Haojie, Peng, Yitian, Cao, Xing'an, Yu, Kang
• Format: Article
• Language: English
• Subjects: Adhesion; Electrified interfaces; Electron; Graphene; Nanofriction; Oxidation
• ISSN: 0169-4332; 1873-5584
• DOI: 10.1016/j.apsusc.2020.146327

The contact resistance is important in the nanofriction of graphene at electrified interfaces. [Display omitted] •Nanofriction of graphene at electrified interface depends on electron transfer.•Dynamic electron transfer decreases electrical potential difference at interface.•Small graphene exhibits lower nanofriction than large graphene.•Nanofriction of graphene at electrified interface negatively correlated with load. Nanofriction properties of graphene at electrified interfaces are important for the application of graphene as a solid lubricant in graphene-based electric-carrying interfaces. The nanofriction experiments based on conductive atomic force microscopy show that dynamic electron transfer determines nanofriction of graphene at the electrified interfaces. Nanofriction at highly conductive interfaces remain constant because the fast electron transfer decreases the electrical potential difference. However, nanofriction at low conductive interfaces increases because electron blocking increases the electrical potential difference. The nanofriction of graphene correlated negatively with loads at low conductive interfaces because high loads decrease the contact resistance to release blocked electrons. Furthermore, large graphene possesses higher nanofriction than small graphene. Scanning Kelvin force microscopy measurements show that the larger electron capacity of large graphene can maintain the electrical potential difference at interfaces. These studies provide beneficial guidelines for the applications of graphene as a solid lubricant at electrified interfaces.