A novel strategy for constructing active anti-corrosive coatings by embedding three-dimensional fiber networks

The corrosion protection effectiveness of micro/nanocontainer-based intelligent coatings significantly depends on their dispersion within the coating matrix. Inspired by the bionic concept of a ‘vascular network’ we designed a polylactic acid (PLA) three-dimensional fiber network incorporating the pH-responsive TiO₂-8-hydroxyquinoline (TiO₂-8HQ) nanotubes using electrospinning technology. These TiO₂-8HQ@PLA networks are crosslinked and evenly dispersed on the Mg alloy surface, responsive to local pH variations. The encapsulated 8HQ inhibitors release rapidly in alkaline conditions, transporting through the network to enable continuous self-healing in multi-defect areas. An epoxy coating applied over the network forms a novel vascular network intelligent coating. Electrochemical and surface analysis tests reveal that 2 %TiO₂-8HQ@PLA-EP provides the most enduring corrosion resistance over 50 days in a 3.5 wt% NaCl solution, with a coating resistance of 2.33 × 10⁶ Ω cm² and charge transfer resistance of 4.81 × 10⁶ Ω cm². Additionally, the network enhances adhesion strength (38.01 MPa) and surface wettability (104.25° ± 0.15°), significantly improving the coating's physical barrier performance. The combination of the micro/nanocontainers technology and vascular network innovative design provides a unique insight into active corrosion control on diverse metals.