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Mussel-Inspired Graphene Film with Enhanced Durability as a Macroscale Solid Lubricant
journal contribution
posted on 2019-08-16, 15:03 authored by Sulin Chen, Bin Shen, Fan Zhang, Hong Hong, Jinshan PanGraphene has exhibited
massive potential as a macroscale solid
lubricant, but its durability is limited due to the weak adhesion
between graphene sheets and the substrate. Here, inspired by mussel
adhesive protein (MAP), effective reinforcement of the graphene–substrate
interaction to attain remarkable enhancement on the durability of
the graphene film is presented. The mussel-inspired graphene (mGr)
film exhibits a coefficient of friction stabilizing at 0.16 up to
490000 sliding cycles in the friction testing against the silicon
nitride ball; in the identical sliding condition, comparatively, the
graphene (Gr) film without MAP only lasts 4300 sliding cycles. The
analysis of Raman and ATR-FTIR demonstrates that, on the one hand,
the MAP film firmly adsorbs onto the substrate via forming metal-catechol
coordination bonds with metal atoms; on the other hand, it establishes
strong interactions with graphene sheets by hydrogen bonding as well
as the π–π overlap. As an interlayer, MAP retains
graphene sheets within the contact interface in the form of a compact
tribo-layer, which results in an over 2 orders of magnitude enhancement
of durability for the mGr film. This strategy of improving the graphene–substrate
adhesion via MAP offers an avenue for the development of effective
and reliable graphene-based solid lubricants for engineering applications.