Epoxy resin/fluorinated multi-walled carbon nanotube composite photothermal superhydrophobic coatings for anti-icing applications

The accumulation of ice and frost in cold environments severely disrupts the normal operation of equipment, making it essential to develop functional surfaces that can delay ice/frost formation and enable rapid removal. Unlike traditional superhydrophobic coatings that rely solely on passive ice delay, this study proposes a novel design integrating both passive ice-delay and active photothermal deicing functionalities. The strategy involves incorporating fluorinated multi-walled carbon nanotube (f-MWCNTs) into an epoxy (EP) matrix to form a hierarchical rough structure while exploiting their strong light absorption capability to impart photothermal responsiveness. The results indicate that after optimizing the filler-to-resin ratio, the coating achieved a water contact angle (WCA) of 156°, a water sliding angle (WSA) of 3.5°, and a light absorption rate of up to 97.49 %, demonstrating both excellent superhydrophobicity and high light absorption properties; at −10 °C, the icing delay time is extended by more than four times compared to the substrate, which is primarily attributed to the air layers within the rough structure effectively retarding heat transfer. At room temperature, the surface temperature increased by 30 °C within 300 s under 1.0 sun irradiation, while under −10 °C, the same irradiation achieved complete ice removal within 6 min, attributable to the exceptional photothermal conversion efficiency of MWCNTs. Moreover, the coating maintained its superhydrophobicity after water impact, sand impact, and tape-peeling tests, demonstrating good mechanical durability, which is primarily attributed to the robust cross-linked network formed between the f-MWCNTs and EP. Overall, the coating provides a promising strategy for anti-icing applications in power transmission, aerospace, and wind energy systems.