A Superhydrophobic Multiwalled Carbon Nanotube/Epoxy Nanocomposite with Photothermal and Electrothermal Properties as Durable Anti-Icing Coating

Long-term icing protection is crucial for low-temperature safety, but traditional methods like mechanical, chemical deicing, and passive thermal protection face high energy use, pollution, and limited effectiveness. We developed a multiwalled carbon nanotube-based superhydrophobic composite coating with a micronano structure that exhibits excellent photothermal and electrothermal effects. Its superhydrophobicity delays the freezing time of a 6 μL water droplet to 353 s at −20 °C, extending to 1569 s under one-sunlight intensity (∼1 KW·m–2). It indicates that the active and passive cooperative strategy was efficient to improve the delayed freezing time although still limited. As a result, more energy output was used, such as the freezing time increasing to a staggering 240 min when supplemented with 5 V voltage (∼4 KW·m–2). Obviously, the final freezing was due to the excessive consumption of output energy by the evaporation effect and the gradual loss of superhydrophobicity. Therefore, it is expected that a longer delay in the freezing time can be achieved by designing the programmed pulse frequency of the output voltage even at a lower energy output. As expected, the freezing time is delayed to 600 min by supplementing 15 V voltage at a low frequency of 4 s/100 s under one-sunlight intensity (∼1.44 KW·m–2). This work develops strategies for long-term icing protection, addressing challenges in aerospace and rail transit.