A multi-layer flexible photothermal titanium nitride-based superhydrophobic surface for highly efficient anti-icing and de-icing

Ice accumulation presents a significant challenge for various residential activities and industrial facilities. Most current de-icing methods are time-consuming and costly. Photothermal superhydrophobic surfaces have garnered significant attention in the field of anti-icing and de-icing due to their environmentally friendly and energy-saving characteristics. However, obtaining photothermal superhydrophobic surfaces with both reliable icing delay and effective photothermal de-icing capabilities at ultra-low temperatures (<-30 °C) remains significantly challenging. In this study, we prepared a multilayer flexible photothermal TiN-based superhydrophobic surface (ML-SHS), comprising an FAS@SiO₂/TiN superhydrophobic layer and a PDMS/Triton X-100 flexible supporting layer. The optimal ML-SHS exhibits excellent superhydrophobicity (a water contact angle of 162.7° and a sliding angle of 2°) and an average light absorption of 95.6%, and generates a substantial surface temperature increase of 80.2 °C under 1 sun illumination. Droplets easily roll off the ML-SHS at -10 °C without solar illumination and at -35 °C under 1 sun illumination, demonstrating excellent passive anti-icing capability. Due to its excellent photothermal conversion and thermal constraint capabilities, the accumulated ice layer on the ML-SHS rapidly melts within 450 seconds at -20 °C under 1 sun illumination. The ML-SHS also possesses self-cleaning properties, mechanical durability, and chemical stability, ensuring the usability of the superhydrophobic surface under harsh conditions. Our study may offer a novel approach for the design and fabrication of photothermal superhydrophobic surfaces, facilitating efficient passive anti-icing and active de-icing in practical applications.