Robust All-Waterborne Superhydrophobic Coating with Photothermal Deicing and Passive Anti-icing Properties

The compelling integration of superhydrophobic coatings with light-to-heat conversion capabilities has garnered substantial interest due to their dual functionality encompassing passive anti-icing and deicing attributes. However, the insufficient mechanical stability and the environmental and human health concerns stemming from the extensive use of organic solvents limit their practical application. In this study, an all-waterborne superhydrophobic photothermal coating (PCPAS) was prepared through the synergy of composite micro-nanoparticles derived from carbon nanotubes (CNT), polydopamine (PDA), and Ag particles with fluorine-containing polyacrylic emulsion (PFA). The PDA provided active sites for Ag⁺ reduction reaction and enhanced the interfacial interaction between CNT and Ag particles. The interfacial enhancement enabled the coating to maintain stable superhydrophobicity after 260 times sandpaper abrasion and 240 times tape peeling. Simultaneously, the composite micro-nanoparticle's light-to-heat conversion ability gave the coating excellent anti-icing/deicing capabilities. Under the condition of -20 °C, the freezing time of 30 μL of water droplets was extended to 392 s, and 2 × 2 × 2 cm ice cubes placed on the surface of the coating could completely melt after only 1142 s under simulated sunlight irradiation with a 1 kW/m² intensity. In addition, the coating also had suitable self-cleaning properties and substrate applicability. The comprehensive attributes of this all-waterborne photothermal superhydrophobic coating render it a promising contender for anti-icing and deicing applications in challenging outdoor environments.