Hybrid g‐C ₃ N ₄ /Graphene Nanocoatings for Enhanced Corrosion Protection of Steel Anodes

The growing need for sustainable ways to prevent corrosion has led to progress in smart nanocoating, especially for steel structures in marine and industrial environments. Although sacrificial anode cathodic protection is still widely used, it has some drawbacks, such as anode wear, uneven current flow, and negative environmental effects. Recent advances in nanotechnology have introduced new materials like graphitic carbon nitride (g‐C 3 N 4 ) nanocomposites and graphene‐based derivatives for use in smart coatings. These materials have adjustable band gaps, high chemical stability, excellent electron movement, and the ability to be modified for specific functions, making them useful for coatings that can heal themselves, work with light, and have good electrochemical properties. This review compares g‐C 3 N 4 nanocomposites and graphene‐based materials as advanced nanocoating for improving the performance of sacrificial anodes in protecting steel. The key areas covered include how these materials are made, how they can be modified, their coating structures, their electrochemical behavior, their durability, and how they can be used with sacrificial anodes. The review emphasizes the synergistic benefits of integrating g‐C 3 N 4 and graphene‐based systems for enhanced cathodic protection and explores strategies for their large‐scale industrial implementation.