Synthesis and characterisation of an iron‐ion‐responsive coating with core–shell electrospun fibres containing a chelation agent

A self‐healing coating containing an electrospun nanofibre encapsulating 3,4,5‐trihydroxy benzoic acid cyclohexyl ester (GACE) was prepared. Scanning electron microscopy and transmission electron microscopy demonstrated that the nanofibre had a core–shell structure. The shell thickness of the electrospun fibre was approximately 270 nm, while the core thickness was approximately 380 nm. The self‐healing process of the coating containing GACE nanofibres over a carbon steel surface was simulated in a 3.5 wt% NaCl solution for 30 days. Fourier‐transform infrared spectroscopy analysis revealed that the synthesised GACE reacted with iron ions and formed a stable Fe–O–C compound, which could repair the scratched coating. The self‐repair performance was evaluated through electrochemical measurements, and then a healing model was developed.