Electrodeposited graphene/layered double hydroxides micro/nanocontainers for both passive and active corrosion protection

Abstract

The poor dispersibility of layered double hydroxides (LDHs) is considered to be the main drawback limiting their application in anti-corrosive coatings. In this work, the problem is solved by combining LDHs with graphene (Gr). A facile electrochemically assisted deposition technique (EAT) is developed to prepare Gr/LDH micro/nano-containers. The high-barrier Gr and LDHs synergistically build a ‘labyrinth effect’ to lengthen the diffusion path of corrosive mediums. Moreover, corrosion inhibitors can be released from the interlayer galleries of LDHs and impede corrosion of metal substrate by substituting the aggressive ions. Therefore, the polyvinyl butyral (PVB) coatings doped with Gr/LDH micro/nano-containers pre-loaded with inhibitors 2-Mercaptobenzothiazole (MBT) have both passive and active corrosion protection properties and provide excellent protection to copper substrate.