Study on the Fabrication and Tribological Behavior of Self-Assembled Functionalized Graphene Oxide in Water

Abstract A new lubricating coating with functionalized graphene oxide (fGO) consisting of graphene oxide (GO) with different oxidation degrees, n-octylamine basal plane functionalized GO (bGO), and edge functionalized GO (eGO) was developed with or without 3-aminopropyltrimethoxysilane (APTMS) to reduce friction in macroscale contact with water. The optimal preparation condition of the coating was obtained by the single factor evaluation of a series of factors (20% APTMS aqueous solution, 12 hours immersion time, 0.05 mg/mL GO aqueous solution, and 100 °C curing temperature). The effect of the oxidation degree and functionalization of GO on the friction-reducing and anti-wear behavior of the coating was explored. The coatings with a higher GO oxidation degree exhibited better friction-reduction and anti-wear performance. In addition, the friction-reducing capability of the APTMS-bGO coating was greater than that of APTMS-eGO.