University of Central Florida,
Keywords: graphene, oil, gas
Summary:In this study, we present a novel way to mass produce anti-corrosion graphene based ceramic coating using plasma spray. The powder feedstock used in plasma spraying is prepared from the jar milling mixing of reduced graphene oxide (RGO) and alumina powder. RGO is synthesized by top down approach in which micron sized graphite is converted to multilayer graphene oxide by milling. Plasma spraying is carried out using SG-100 gun, wherein the decomposition of graphene is prevented by in-house designed plasma shroud to provide inert Argon atmosphere. The internalization of RGO in the alumina matrix of plasma sprayed coating was demonstrated using SEM and EDX. The oxidation state of the graphene is analyzed using Raman spectroscopy which shows partial oxidation state in the plasma sprayed coating in contrast to the reduced state in the powder feedstock. Corrosion testing in severe salt water corrosion environment showed 80% reduction in the corrosion current as compared to the pure alumina coating. The plasma sprayed graphene-alumina coating is treated with reducing agent to reduce the graphene which was oxidized during the plasma process and resulted in 96% reduction in the corrosion current.