The long-term degradation behavior of the durable superhydrophobic coating on Al matrix

Abstract

The corrosion of aluminum and its alloys triggered by the aggressive environment seriously affects the service life and causes great economic loss. Superhydrophobic surface have been applied to deal with this problem, but their natural vulnerability cannot resist the intense external damage. Herein, a durable superhydrophobic coating is fabricated by combining the electrochemical growth of TiO2 nanoparticles in the aluminum anodic oxide (AAO) coating with modification of octadecyl trimethoxysilane (OTS), and its long-term corrosion behaviors are investigated through the comparative analysis during the static immersion test. The superhydrophobic AAO-TiO2@OTS coating exhibits the optimal hydrophobicity and corrosion resistance among all samples after being soaked in 3.5 wt% NaCl solution for 28 days, and the synergistic effects of OTS network, AAO layer and TiO2 nanoparticles endow the coating with the durable corrosion resistance. Thus, the integration of low-surface-energy modifier and hard porous frame is beneficial to improve the durability of superhydrophobic coating, and it is anticipated to propose a potential guidance for corrosion protection of metal and its alloys during the long-term service process.