Corrosion-resistant coatings: advances in deposition methods, nanostructures, and self-healing films

The degradation of materials due to corrosion becomes an economic liability and creates adverse environmental problems in critical sectors of the aerospace, automobile, marine, and energy industries. To tackle these challenges, the development of advanced coatings is required. This is an in-depth review of recent developments in corrosion-resistant coatings, with an emphasis on nanostructured coatings, deposition techniques such as Physical Vapor Deposition (PVD) and Chemical Vapor Deposition (CVD), and self-healing films, which can expand the lifetime of materials in aggressive environments. It includes a detailed account of mechanical durability, electrochemical stability, and hydrophobicity, and the coatings considered showed graphene-promoted layers, polymer–ceramic hybrids, and metal–organic frameworks (MOFs) and exhibited a 75% rate of corrosion resistance under harsh environmental conditions. Self-healing coatings with healing efficiencies of between 85 and 90% and the sustainability of bio-based polymers are especially considered. Despite significant advances, scalability and long-term durability under synergistic environmental stressors (humidity, salt, temperature) remain daunting challenges, along with an appropriate life cycle assessment. Emerging areas such as AI-designed hybrid materials, 4D printing of self-healing systems, and smart coatings for real-time corrosion monitoring lay out an exciting blueprint for future research and industrial translation.