Self-Healing Behavior of TiO2 Nanotube Array-Stearic Acid Composite Coatings in 0.6M NaCl Solution Environment

The corrosion protection performance differences between TiO 2 nanotubes of varying diameters combined with the same corrosion inhibitor were investigated. TiO 2 nanotube arrays with distinct diameters were grown in-situ on a titanium substrate by adjusting the anodic oxidation voltage. Subsequently, a stearic acid composite coating was formed on the array surface via a chemical bath process. The electrochemical corrosion resistance, fouling resistance, and self-healing behavior of this superhydrophobic composite coating were comprehensively evaluated in both air and solution environments. In-situ monitoring of surface corrosion evolution at different interfaces in 7 days was performed using scanning vibrating electrode technology. Results indicate that, under identical corrosion inhibitor loading, the coating's corrosion protection performance is significantly influenced by TiO 2 nanotube diameter. Furthermore, the nanotube array exhibits the capacity to store stearic acid, which is released upon coating damage, conferring self-healing properties to the interface in both air and solution environments. This study provides novel insights for the design of corrosion inhibitor carrier structures and self-healing anti-corrosion coatings.