Chapter24 - Nanomaterials as corrosion inhibitors

Abstract

Nanomaterials (NMs) are established as one of the potential classes of anticorrosive materials. Obviously, these materials acquire various salient features including surface-area-to-volume ratio that make suitable candidates to replace the traditional corrosion inhibitors. The use of NMs as corrosion inhibitors is associated with various advantages. Some of the commonly used anticorrosive NMs are metal oxides and their composites, CNTs (SWCNTs and MWCNTs) and their covalent and non-covalent functionalized derivatives/composites, G, GO, and their covalent and non-covalent functionalized derivatives/composites, nanofibers and nanocontainers. Obviously, covalent and non-covalent functionalized derivatives exhibit reasonably high dispersibility in the aqueous solution. Nevertheless, most of the NMs are utilized as anticorrosive materials in anticorrosive formulations. Recently, few reports have been reported in which suitably modified graphene oxide using organic compounds such as aminoazobenzene, diaminobenzene, diaminopyridine, diazopyridine, and polyethyleneimine are tested as the excellent aqueous phase anticorrosive materials. In the aqueous solution, NMs behave as mixed- and interface-type corrosion inhibitors as they become effective by adsorbing at the interface of metal and electrolyte and retarding the anodic and cathodic Tafel reactions.