Engineering hollow mesoporous silica nanocontainers with molecular switches for continuous self-healing anticorrosion coating

Here we report a new light-responsive and self-healing anticorrosion coating by incorporating hollow nanocontainers with smart molecular switches. The smart coating was obtained by immobilizing photoresponsive azobenzene molecular switches in the nanopores of hollow mesoporous silica nanocontainers. These novel nanocontainers with hollow cavities can encapsulate active molecules under visible light and release them under ultraviolet irradiation. The release of benzotriazole from the hollow nanocontainers can be started and stopped with high controllability, which provides an effective approach to avoid excessive release of active molecules after corrosion healing. The results of scanning vibrating electrode technique demonstrate that the azobenzene molecular switch modified hollow mesoporous silica nanocontainers exhibit excellent continuous photosensitive self-healing performance for improving the long-term performance of aluminium alloy.