Upcycling of biomass waste into photothermal superhydrophobic coating for efficient anti-icing and deicing

Superhydrophobic surfaces coupling with photothermal effect, as a passive solution independent of external energy input, have shown promising perspectives for anti-icing and deicing. However, most hydrophobic photothermal materials are costly and require complicated fabrication processes, which limit their development in large-scale applications. Here, a facile method is proposed to fabricate superhydrophobic photothermal anti-icing coating using commercially available biochar (BC) and low-cost titanium nitride (TiN) nanoparticles. The coating displays superior photothermal conversion and anti-icing performance, benefiting from the micro-nano hierarchical structure's light trapping effect and high surface roughness. Meanwhile, the coating shows an extra-long anti-icing time of ∼831s for water droplets, which is ∼17 times longer than pure BC coating. The covering frost and ice can be melted into droplets under the illumination of sunlight and roll off rapidly, leaving a dry surface. The superhydrophobic photothermal coating may promote the development of anti-icing and deicing surfaces in outdoor applications.