## 2 Utilization of Various Nano-Modified Coatings for Corrosion Mitigation
### Self-Healing-Based Nano-Modified Coating  
Among the best ways to avoid corrosion of highly chemically reactive metals and their alloys is to coat and cover them. When corrosive media permeate the covering and contact with the alloy substrate, pristine coverings over metals created using conventional techniques such chemical conversion, electroless Ni, and plasma electrolytic oxidation (PEO) cannot continue to defend against corrosion [14; 72]. To enhance protection against corrosion and extend the lifespan of a coating, CIs are physically applied to the sealant matrix. However, this has the downside of early inhibitor leaking preceding the commencement of corrosion, which reduces the effectiveness of corrosion inhibition. The unpredictable discharge of inhibitors is frequently addressed by the development of smart self-healing nanocoatings, which have gained significant interest in the field of corrosion research during the past ten years. These coatings are considered to be \"active\" coatings with the ability to recover from an initial scratch or imperfection and so persist to provide structures underneath with corrosion prevention. The responsiveness of coatings to exterior stimuli is a characteristic shared by all systems [73]. A trigger's reaction could be instantaneous or managed through evaluation of the triggers. They are typically coatings made of a top coat and a primer. The top layer might deteriorate and act as a trigger when exposed to UV light. A capsule's ability to discharge an active ingredient is stimulated by light. The material can restore the top coat's damage. A novel method for building pH-responsive smart nanocontainers (MSNMBT@LDH) was provided by [PERSON] et al. [66]. By using pH-regulated MSN-MBT@LDH nanocontainers comprising an MBT-loaded MSN core and a cover made of LDH nanosheets, they show how to fabricate a proactive SNAP covering over Mg alloy with greatly improved corrosion resistance. The mechanized MSN-MBT@LDH nanocontainers exhibited a pH-dependent liberation of MBT from MSN in acidic circumstances and were readily produced by a straightforward two-step sorption procedure. The SNAP coating incorporating MSN-MBT@LDH nanocontainers showed a considerable improvement and enhanced resilience in corrosion protection in NaCl medium as contrasted to plain SNAP covering. This was partly attributable to the trapping of hostile Cl\({}^{-}\) ions availing the benefit of the extra LDH nanoplates that were not deposited over the MSN interface, and mostly to the corrosion inhibition of MBT caused by flaws occurring at the coating interaction. Researchers presume the suggested approach will open the path to the thrilling development of an inhibitor-loaded nano reservoir as well as its comprehensive implementation for the preparedness of smart corrosion protection coating materials in the sector of corrosion science due to the reduced expense and ease of development of MBT-loaded and pH-responsive MSN-based nanocontainers in this work. Similarly, incorporating nano-oxides of various metals (MONPs), such as CuONPs, Fe\({}_{3}\)O\({}_{4}\)NPs, and NiONPs, into primary alginate-modified cellulose (PAC), [PERSON] et al. [74] effectively produced unique self-healing eco-sustainable nano-modified coating. The results from spectroscopy showed that the synthesis of PAC/CuONPs, PAC/Fe\({}_{3}\)O\({}_{4}\)NPs, and PAC/NiONPs with uniform distributions and particulate sizes of 23, 10, and 43 nm, correspondingly, was effective in producing PAC/MONPs nanocomposites. By using gravimetric and electrochemical methods, the protective effect of the as-prepared PAC and PAC/MONPs nanocomposites for C-steel corrosion in 1M HCl was investigated. Using 250 ppm of PAC/Fe\({}_{3}\)O\({}_{4}\)NPs, PAC/CuONP, and PAC/NiONPs, the IE% was 93.2, 88.1, 96.1, and 98.6%, correspondingly.