Dual-shell n-OD@PDA phase-change microcapsule reinforced superhydrophobic coatings with enhanced photothermal anti-/de-icing performance

Photothermal superhydrophobic coatings hold great potential for anti-icing/de-icing, but are severely limited by strong dependence on solar illumination and poor stability in dark or low-light environments. Herein, a multifunctional superhydrophobic coating reinforced with dual‑shell phase‑change microcapsules (n‑OD@PDA) is fabricated for synergistic passive anti‑icing and active de‑icing applications. The microcapsules consist of an n-octadecane core for latent heat storage, a SiO₂ inner shell for structural stability, and a polydopamine outer shell enabling broadband photothermal conversion. Incorporated into a fluorinated epoxy matrix, the resulting coating exhibits a hierarchical micro-/nanostructure with excellent superhydrophobicity (Contact angle 151°, Sliding angle 2°). Under 1 Sun irradiation, the coating rapidly heats to 63°C, representing a 96.3% enhancement compared with PDA-free systems. Owing to the phase-change heat storage and release, stable thermal regulation is maintained even under weak or no illumination. At -20°C, the freezing time of water droplets is prolonged by approximately 25 times, and the coating possesses ultra-low ice adhesion strength (10-15 kPa) and rapid de-icing/defrosting performance. This work provides a promising all-weather strategy for high-efficiency anti-/de-icing coatings in harsh low-temperature environments. Download: Download high-res image (246KB) Download: Download full-size image