Self-healing and corrosion-sensing multifunctional coatings containing pH-sensitive TiO₂-based composites

Area of Science:

• Materials Science
• Corrosion Science
• Nanotechnology

Background:

• Corrosion poses a significant threat to metal infrastructure, necessitating advanced protection strategies.
• Developing smart coatings with self-healing and sensing capabilities is crucial for extending material lifespan.
• pH-responsive systems offer controlled release of active agents, enhancing protective efficiency.

Purpose of the Study:

• To develop a novel pH-responsive nanocontainer system for on-demand release of corrosion inhibitors.
• To create a multifunctional epoxy coating with self-healing and corrosion-sensing properties.
• To evaluate the cooperative protective effect of 1,10-phenanthroline and tripolyphosphate ions.

Main Methods:

• Fabrication of polyelectrolyte-encapsulated mesoporous TiO2 nanocontainers (MTNs) loaded with corrosion inhibitors (Phen and Tpp).
• Encapsulation of nanocontainers within an epoxy coating (EP).
• Characterization of the hybrid coating's self-healing, corrosion-sensing, and protective performance.

Main Results:

• The Phen-Tpp@MTNs-PDDA/EP coating exhibited excellent self-healing properties and long-term corrosion protection.
• A distinct color change was observed, indicating the coating's corrosion-sensing capability.
• The synergistic effect of Phen and Tpp enhanced the overall corrosion inhibition.

Conclusions:

• The developed pH-responsive nanocontainer system effectively controls corrosion inhibitor release.
• The hybrid coating demonstrates multifunctional capabilities, including self-healing and corrosion sensing.
• This approach offers a promising strategy for advanced metal corrosion protection.