Metals and metal oxides polymer frameworks as advanced anticorrosive materials: design, performance, and future direction

Metals (Ms) and metal oxides (MOs) possess a strong tendency to coordinate and combine with organic polymers to form respective metal-polymer frameworks (MPFs) and metal oxide polymer frameworks (MOPFs). MPFs and MOPFs can be regarded as composites of organic polymers. MPFs and MOPFs are widely used for industrial and biological applications including as anticorrosive materials in the aqueous phase as well as in the coating conditions. The presence of the Ms and MOs in the polymer coatings improves the corrosion inhibition potential of MPFs and MOPFs by improving their self-healing properties. The Ms and MOs fill the micropores and cracks through which corrosive species such as water, oxygen, and corrosive ions and salts can diffuse and destroy the coating structures. Therefore, the Ms and MOs enhance the durability as well as the effectiveness of the polymer coatings. The present review article is intended to describe the corrosion inhibition potential of some MPFs and MOPFs of some most frequently utilized transition metal elements such as Ti, Si, Zn, Ce, Ag, and Au. The mechanism of corrosion inhibition of MPFs and MOPFs is also described in the presence and absence of metal and metal oxides.