Silica/Polymer Double-Walled Hybrid Nanotubes: Synthesis and Application as Stimuli-Responsive Nanocontainers in Self-Healing Coatings

We report the development of silica/polymer double-walled hybrid nanotubes, which consist of a hollow cavity, a porous silica inner wall, and a stimuli-responsive (pH, temperature, and redox) polymeric outer wall, as a novel nanocontainer system. The length, diameter, wall thickness, and aspect ratio of the hybrid nanotubes are precisely controlled in the range of 48–506 nm, 41–68 nm, 3–24 nm, and 1.2–7.6, respectively. The hybrid nanotubes loaded with active molecules exhibit morphology-dependent release and pH-, temperature-, redox-responsive release, which enable a wide range of applications from energy storage to drug delivery and self-healing coatings for metal corrosion protection.