Capillary assisted self-assembly and nascent hydrogen reduction of graphene oxide on Al: Formation of C–O–Al bonds under mild condition

Abstract

Graphene has been recognized as reinforcement and/or protective coating for metal materials due to its unique electronic, mechanical properties and chemical inertness. Challenges of graphene agglomeration and weak graphene/metal interfacial bonding still exist during preparation. Here we report a novel method combining capillary-assisted self-assembly with nascent hydrogen reduction technique to one step coat Al foil with layered-stacking graphene. Al foil constructed slit is filled with graphene oxide (GO) suspensions and the generation of nascent hydrogen occurs at the GO/Al interface. The capillary force drives the GO flakes to layer-by-layer assemble on Al foil, as well as increases the reduction depth of GO. X-ray photoelectron spectroscopy (XPS) reveals that the reduced GO (rGO) binds with Al is not just through van der Waals forces, but with a strong interaction of developing C–O–Al bonds. The hydroxyl groups on GO plays an essential role in the formation of such C–O–Al configuration. Al foil coated with rGO through this capillary-assisted self-assembly with nascent hydrogen reduction method show good corrosion resistance compared to the pristine Al and directly drop-casted GO on Al. The proposed method can be readily applied to the fabrication of graphene/metal composites with improved interfaces.