• 文献标题:   Tailoring the Nanostructure of Graphene as an Oil-Based Additive: toward Synergistic Lubrication with an Amorphous Carbon Film
  • 文献类型:   Article
  • 作  者:   LI XW, ZHANG DK, XU XW, LEE KR
  • 作者关键词:   graphene, lubricant additive, amorphous carbon, friction mechanism, reactive molecular dynamic
  • 出版物名称:   ACS APPLIED MATERIALS INTERFACES
  • ISSN:   1944-8244 EI 1944-8252
  • 通讯作者地址:   China Univ Min Technol
  • 被引频次:   0
  • DOI:   10.1021/acsami.0c12890
  • 出版年:   2020

▎ 摘  要

Graphene exhibits great potential as a lubricant additive to enhance the antifriction capacity of moving mechanical components in synergism with amorphous carbon (a-C) as a solid lubricant. However, it is particularly challenging for experiments to accurately examine the friction dependence on the physical nanostructure of the graphene additive and the corresponding interfacial reactions because of the inevitable complexity of the graphene structure fabricated in experiments. Here, we address this puzzle regarding the coeffect of the size and content of the graphene additive at the a-C interface using reactive molecular dynamics simulations. Results reveal that the friction-reducing behavior is more sensitive to graphene size than content. For each graphene structure, with increasing content, the friction coefficient always decreases first and then increases, while the friction behavior exhibits significant dependence on the graphene size when the graphene content is fixed. In particular, the optimized size and content of the graphene additive are suggested, in which an excellent antifriction behavior or even superlubricity can be achieved. Analysis of the friction interface indicates that with increasing graphene size, the dominated low-friction mechanism transforms from the high mobilities of the base oil and graphene additive in synergism to the passivation and graphene-induced smoothing of the friction interface. These outcomes disclose the roadmap for developing a robust solid-liquid synergy lubricating system.