Effect of the graphene-based material on the conductivity and corrosion behaviour of PTFE/graphene-based composites coatings on titanium for PEM fuel cell bipolar plates

Titanium is widely used as a material for bipolar plates (BP) PEM fuel cells, but they require conductive coatings that help with corrosion and have low interfacial contact resistance (ICR). Among many materials, polymer composites reinforced with graphene nanoparticles have the potential to become an effective coating, but the influence of different types of graphene-based materials on the performance remains has not been properly established. In this study, different nanoparticles (graphene monolayers, reduced graphene oxide and few-layer graphene) were used to process PTFE/graphene composite coatings for Ti, and their performance was evaluated. Most of the coating formulations improved the corrosion resistance of the Ti in one or two orders of magnitude, but only the combination of few-layer graphene and carbon black as additive resulted in an ICR of 12 m Omega cm2, in range with the target values.