  Despite the numerous reports on the topic, examples of chemical vapor
deposited (CVD) graphene-based anticorrosive coatings able to provide long-term
protection (i.e., several months) of metals are still unavailable. Here, we
finally present a polymer-graphene hybrid coating, comprising two single layers
of CVD graphene sandwiched by three layers of polyvinyl butyral, that provides
complete corrosion protection to commercial aluminum alloys even after 120 days
of exposure to simulated seawater. The essential role played by graphene in the
hybrid coating is evident when we compare the results from a polymer-only
coating of the same thickness, which fails in protecting the metal after barely
30 days. With the emergence of commercially available large-area CVD graphene,
our work demonstrates a straightforward approach towards high-performance
anticorrosive coatings, which can be extended to other two-dimensional
materials and polymers, for long-term protection of various relevant metals and
alloys.
