A Photothermal Hydrophobic Emulsified Asphalt Coating with Prussian Blue and Polytetrafluoroethylene for Improved Road Anti-Icing and Deicing

Ice formation on roads not only degrades pavement performance but also increases traffic safety hazards. Traditional mechanical and salt deicing methods often damage the pavement structure and pollute the environment. To address these issues, a clean method of preparing the hydrophobic coatings on the road has been developed in recent years. These coatings help reduce water accumulation on road surfaces and delay the freezing process. However, in extreme weather conditions, roads can still develop thick ice layers that are too robust to be broken or removed by vehicle traffic alone. Therefore, incorporating thermal energy becomes essential to decrease the ice accumulation and ease the deicing process. In our study, we prepared coatings by using polytetrafluoroethylene (PTFE) known for its hydrophobic properties, Prussian blue (PB) for its photothermal conversion property, and emulsified asphalt. The contact angle of the water droplet on the surface of the coating is 150.238°. When exposed to 808 nm near-infrared light, the time it took for water droplets on the coating surface to freeze extended up to 18.5 times longer than normal. During deicing test, the time required for ice removal from the coating and for the ice to melt reduced by 90.6% and 80.9%, respectively. Additionally, the inclusion of PB significantly enhanced the durability of the coating. Overall, this coating shows promising potential for application in road anti-icing and deicing processes.