Core-shell mesoporous silica–metal–phenolic network microcapsule for the controlled release of corrosion inhibitor

A novel pH-sensitive corrosion inhibitor capsule was prepared by forming a metal–phenolic network coating on the surface of mesoporous silica via super-assembly. Chemical characterization, including Fourier transform infrared spectroscopy, Brunauer–Emmett–Teller method, X-ray photoelectron spectroscopy and transmission electron microscopy, confirmed the core–shell structure of the capsule. UV–vis measurements revealed the pH-triggered release behavior of the prepared capsule. Study on its inhibition effect verified that the prepared capsule can respond to the changes of pH and provide outstanding protection for copper. Ion exchange was proposed as the mechanism underlying the pH-triggered release behavior of the capsule.