Ultraflexible Photothermal Superhydrophobic Coating with Multifunctional Applications Based on Plasmonic TiN Nanoparticles

Abstract Photothermal superhydrophobic coatings are essential for a variety of applications including anti‐icing and light‐driven self‐propelled motion. However, achieving a flexible and durable superhydrophobic coating with high photothermal efficiency and long‐term stability is still challenging. Herein, a facile and eco‐friendly approach to realizing a superhydrophobic coating with excellent flexibility is proposed. The coating is obtained by spraying titanium nitride (TiN) nanoparticles embedded in polydimethylsiloxane (PDMS) solution onto various substrates. A tight binding between the substrate and nanoparticles occurs that offers the coating the mechanical robustness to endure bending, twisting, abrasion, and tape peeling. The water repellency is retained even after 500 cycles of bending–twisting tests. Combined with the micro–nanoscale porous structure of the surface and plasmonic property of TiN nanoparticles, the coating shows excellent superhydrophobicity and high photothermal conversion properties. The equilibrium temperature of the coating is as high as 130 °C at room temperature under 1 W cm⁻² of 808 nm near‐infrared laser irradiation. Due to its flexible property, the coating can be easily applied to irregular surfaces, which, together with the excellent anticorrosion, anti‐icing, and defrosting performances, makes it a reliable resource for multifunctional applications. This work offers a novel technological approach to flexible devices, wearable electronics, and smart textiles.