Anti-corrosion Self-healing Behavior of Sol-gel Coating with Nano-tube Loaded with Inhibitor

Using P25 nanoparticles as precursor, titanate nanotubes were prepared by hydrothermal method. Benzotriazole (BTA) was loaded into the titanate nanotubes, and then the BTA-containing nanotubes (referred to as nanotubes) were added to sol-gel coating. A UV spectrophotometer was used to measure the release of BTA in acidic solutions with different pH. The corrosion-inhibiting and self-healing behavior of the coating containing nanotubes was studied through micro-area electrochemistry and salt spray tests. The results showed that as the pH of the solution decreased, the releasing amount of BTA gradually increased; the anti-corrosion performance of the nanotube-modified coating increased significantly. And when the coating was damaged, BTA could be released to protect the aluminum alloy substrate and prevent the substrate from being corroded by external media, so that the coating had a corrosion-inhibiting and self-healing ability.