Silica nanocontainers for active corrosion protection

Area of Science:

• Materials Science
• Corrosion Science
• Nanotechnology

Background:

• Protective coatings are crucial for preventing metallic material degradation.
• Existing anticorrosion strategies often lack long-term efficacy and self-healing capabilities.
• Nanocontainers offer a promising approach for controlled release of active agents.

Purpose of the Study:

• To synthesize and characterize novel silica nanocapsules (SiNC) for corrosion inhibitor delivery.
• To investigate the stimuli-responsive release kinetics of 2-mercaptobenzothiazole (MBT) from SiNC.
• To evaluate the performance of SiNC-MBT in protective coatings for aluminum alloy 2024.

Main Methods:

• One-stage synthesis of silica nanocapsules (SiNC) with an empty core and gradual mesoporosity.
• Loading of corrosion inhibitor 2-mercaptobenzothiazole (MBT) into SiNC.
• Study of inhibitor release kinetics under varying pH and NaCl concentrations.
• Dispersion of SiNC-MBT in coating formulations and evaluation of corrosion protection on Al alloy 2024.
• Assessment of self-healing properties in coated materials with induced defects.

Main Results:

• Successfully synthesized SiNC with high loading capacity and prolonged, stimuli-triggered release of MBT.
• Release profiles of MBT from SiNC demonstrated clear dependence on pH and chloride concentration.
• SiNC-MBT significantly reduced corrosion activity on aluminum alloy 2024, outperforming direct inhibitor addition in coatings.
• Observed self-healing behavior in modified coatings, both before and after defect creation.

Conclusions:

• Developed functional nanoreservoirs (SiNC) offer a novel platform for advanced anticorrosion protection.
• The unique structure of SiNC enables controlled release of corrosion inhibitors, enhancing coating performance.
• These nanocontainers show high potential for next-generation active and self-healing protective coatings.