Smart self-healing and fluorescence-driven self-indicating coating with enhanced anticorrosive effectiveness: An integrated triple-action armour through experimental and theoretical synchronization

Coating technology has become a potential contender for combating the substantial challenges originating from metallic corrosion. In contrast to the conventional methodologies, this work introduces an epoxy based self-healing coating (EP-SHC) endowed with a triple-function formula: anticorrosive, self-healing, and self-reporting. In the present work, fluorescence labeled-healing agent loaded microcapsules (MCPs) were incorporated within the coating matrix to protect the underlying mild steel (MS) surface. The EP-SHC exhibited significantly enhanced corrosion resistance, as evidenced by its high impedance value (7.5 × 10 5 Ω cm 2 ). Moreover, upon damage to the coated surface, the fluorescence intensity increased, providing a visual indication of the microcrack location. It was observed that the MCPs are capable of not only detecting the precise location of the microcracks but also effectively repairing the damaged areas within 24 h at room temperature. At the same time, EP-SHC exhibits effective adhesion strength up to 336 h of immersion in a brine solution. The excellent barrier property of the formulated coating was further validated by advanced theoretical analyses like density functional theory (DFT), electrostatic potential map (ESP), Fukui analysis, free volume calculation, and mean square displacement (MSD). This innovative technique offers a sustainable and effective solution for identifying and simultaneously repairing microcracks present on the surface of epoxy coatings. • FTO/PMMA MCPs were synthesized by one-pot in-situ polymerization-based oil-in-water emulsion technique. • The MCP-based smart coating was integrated with triple functionalities: Anticorrosive, self-healing and self-reporting. • The EP-SHC achieved auto-repair of micro-damages within 24h at room temperature. • The coating exhibits effective adhesion strength upto 336h of immersion in brine solution. • Advanced theoretical analysis like DFT, ESP, free volume calculations, and MSD were performed for molecular level insights.