NIR-responsive self-healing superhydrophobic coatings: Enhanced, corrosion resistance, and mechanical stability

Superhydrophobic coatings with special wettable surfaces hold significant promise for applications in self-cleaning, anti-corrosion, and other industrial domains. However, their practical implementation is hindered by fragile mechanical durability and poor chemical stability. This study addresses these limitations by developing near-infrared (NIR)-responsive self-healing superhydrophobic coatings using a one-step spraying method. Epoxy resin serves as the shape memory matrix, while DTMS@PDA@SiO 2 @CNTs particles function as photothermal conversion agents and hydrophobic components. The optimal synthesis parameters—reaction pH of 8.5, a carbon nanotube (CNTs) to TEOS ratio of 1:3, and a dopamine (DA) to CNTs ratio of 1:1—were determined to maximize photothermal conversion and coating performance. The coatings demonstrated exceptional hydrophobicity, with a water contact angle of 167° and a scratch repair efficiency of up to 82 % under NIR irradiation. Even after structural damage, their superhydrophobic properties could be restored by activating the shape memory effect through photothermal heating. The coatings exhibited superior stability against mechanical wear, maintaining hydrophobicity after sandpaper abrasion and tape peeling. They also showed excellent resistance to chemical corrosion, effectively preventing ion penetration and maintaining performance in acidic, alkaline, and saline environments. These findings highlight the potential of NIR-responsive self-healing superhydrophobic coatings to overcome existing durability and stability challenges, extending their applicability in harsh industrial and environmental conditions.