Intelligent protective coatings for marine environments: active/passive synergistic anticorrosion, corrosion warning, and efficient antibacterial based on MUP heterostructure

The combination of mechanical damage, electrochemical corrosion, and microbial corrosion in the marine environment presents a significant challenge to the long-term protection of organic coatings. Developing intelligent protective coatings with anticorrosion, early-stage corrosion warning, and antibacterial properties is a promising task. In this study, we synthesized Ce-UiO with a hierarchical porous channel structure using a microemulsion template method and loaded it with 1,10-phenanthroline (Phen) into its pores as a corrosion-responsive probe. Furthermore, we constructed Ti 3 C 2 T x /Ce-UiO/Phen (MUP) heterostructures through electrostatic interactions between Ti 3 C 2 T x and Ce-UiO. MUP heterostructure not only achieved active/passive corrosion protection but also integrated the functions of photocatalytic antibacterial activity and early-stage corrosion warning, achieving a synergistic effect of "1 + 1 > 2". The MUP/Epoxy (EP) coating demonstrated excellent anticorrosion performance (| Z | f = 0.01 Hz = 9.22 × 10 8 Ω cm 2 ) even under 60 MPa alternating hydrostatic pressure after 10 cycles. Simultaneously, Phen generated dual-mode signals through chromogenic reaction and fluorescence changes, enabling real-time corrosion monitoring. Additionally, the MUP heterostructure imparted efficient antibacterial properties to the coating via a synergistic mechanism of "bacterial capture + reactive oxygen species killing". After 24 h of light exposure, the antibacterial rate of the MUP/EP coating reached 99.0%. This work provides a novel strategy for designing and applying the next generation of intelligent protective coatings.