Facile preparation of redox-responsive hollow mesoporous silica spheres for the encapsulation and controlled release of corrosion inhibitors

The redox-responsive hollow mesoporous silica sphere (HMSS) as smart nanocontainer demonstrates great potential for active agent storage and controlled release. In the present work, HMSS was firstly prepared by surfactant assisted selective etching method. Then, target corrosion inhibitors, 2-mercaptobenzothiazole (MBT) molecules, were loaded and encapsulated with redox-responsive supramolecular nanovalves, ZnO quantum dots. Results reveal that obtained HMSS exhibits a hierarchical mesoporous structure consisting of hollow cavity and mesoporous shell. Corrosion inhibitors were successfully loaded and capped in HMSS nanocontainers, showing on-demand release behavior under specific environment. Moreover, the release efficiency gradually increased with increasing dosage of the reducing agent. Therefore, the novel smart nanocontainers with redox-responsive characteristics will offer a great promise for the development of new generation nano delivery system for corrosion protection accompanying redox environment change.