Suspension plasma sprayed copper-graphene coatings for improved antibacterial properties

Abstract

Copper has a long history of use as a biocidal agent. Recent studies have demonstrated that incorporating graphene into copper coatings improves their antibacterial properties. However, the implementation of copper-graphene composite coatings is currently limited by the cost and scarcity of copper, as well as the difficulty of achieving a homogeneous distribution of graphene within the copper matrix. In this study, a new approach was developed to utilize an inductively-coupled radio frequency plasma torch to spray a uniform composite coating of copper nanoparticles and graphene nanoflakes (GNFs) onto a metal substrate. The resulting composite coatings exhibit microstructural uniformity, coating splats cohesion, and GNFs retention and dispersion within the Cu matrix. Furthermore, the Cu-GNFs coatings demonstrated strong antibacterial properties, with a 99% reduction of Escherichia coli bacteria within 1 h.