Corrosion Protective Properties of Silane Functionalized Graphene Oxide Film on AA2024-T3 Aluminum Alloy

Abstract

3-glycidoxypropyl-trimethoxysilane (GPTMS) functionalized graphene oxide (GO) was used to synthesize graphene-based film for corrosion protection of AA2024-T3 aluminum alloy. GO covalently reacted with the silanol group from the hydrolyzed GPTMS monomer, forming silane functionalized GO (silane-GO) linked by C-O-Si covalent bonds. The silane coupling agents acted as a ‘bridge’ to link GO to adjacent GO and to the metal surface by covalent bonds. The corrosion protective properties of silane-GO film were determined by electrochemical measurements and immersion tests. Results indicated that silane-GO film provided effective protection for the metal substrate and the readily corrodible areas (at the periphery of protruding constituent particles). This was due to the good barrier property from layered GO, the filled defects and gaps between GO, and the enhanced adhesion strength of GO to adjacent GO and the film to the substrate. The protective efficiency of silane-GO film was up to 95.0%. The successful application of silane-GO film on AA2024-T3 aluminum alloy suggests that there is the considerable potential for broad application of graphene-based protective film on metals, even on the metals with corrosion-sensitive areas.