Porous microspheres with corrosion sensing and active protecting abilities towards intelligent self-reporting and anti-corrosion coating

Abstract

In situ detection of corrosion is important and in urgent demand, which is still a challenging task so far. Herein, a smart self-reporting and active anti-corrosion coating was reported by integrating 8-hydroxyquinoline (8-HQ) loaded porous microspheres into the coating matrix. The 8-HQ loaded porous microspheres were prepared by a facile one-pot photopolymerization of an emulsion containing photosensitive monomer and 8-HQ, which could be completed within several minutes. The porosity of microspheres allows for efficient encapsulation of 8-HQ and the loading capacities could reach about 12 wt%. In the obtained porous microspheres, 8-HQ functioned as both the corrosion-sensing species and corrosion inhibitor. These ingeniously designed microspheres could realize the integration of multi functions in single coating. The scratch corrosion caused by mechanical damage as well as pit corrosion beneath coating can be timely reported by an evident fluorescence derived from 8-HQ-Al3+ coordinates, achieving the function of real-time corrosion diagnosing. In the meanwhile, the constructed coating exhibited long-term protective performance for aluminum alloy, which should be attributed to the corrosion inhibition of 8-HQ. This simple but smart porous microsphere provides a feasible and effective way to prepare intelligent coatings with corrosion protecting and corrosion sensing functions.