Wear and anticorrosive properties of graphene oxide-cellulose nanofiber composite coatings

Graphene oxide (GO) presents great potential in lubricating and anticorrosive coatings. However, the durability of GO coatings is seriously limited due to its typical brittleness. Cellulose nanofiber (CNF) is a kind of versatile natural material, which is widely used as nanofillers to enhance the mechanical and anticorrosive properties of various matrix materials. In this work, graphene oxide-cellulose nanofiber (GO-CNF) composite coatings with different CNF mass fractions were fabricated on stainless steel substrates by spraying technique. The results of nanoindentation and tribological tests indicate that GO-10.0 wt% CNF composite coating presents the optimum mechanical and tribological properties, with low coefficient of friction (COF<0.2) and long service life of more than 10,000 cycles. In addition, electrochemical corrosion behavior and salt spray experiments demonstrate that the GO-40.0 wt% CNF composite coating can still maintain excellent anticorrosive properties and integrity after one week of long-term corrosion. This result shows that a certain amount of CNF can effectively improve the anticorrosive properties and enhance the protective effect of GO coatings. This strategy of enhancing the tribological and anticorrosive properties by introducing CNF into GO coatings provides a simple and rapid route for developing graphene-based functional coatings for practical engineering applications.