Affordable Biogenic Anti-Icing Surfaces

In this study, the development of low-cost biogenic anti-icing coatings that heat up upon irradiation is reported. Charcoal from coconut shells is milled into various particle sizes (Ranging from <90 µm to >600 µm) and immobilize onto glass using epoxy adhesives is reported. These substrates are subsequently rendered hydrophobic through surface treatment with rapeseed oil (RO), squalene (SQ), a beeswax extract (BW), or a commercially available alkane-based release spray (RS). Results showed that a particle size distribution of 90–250 µm is optimal for achieving strong hydrophobicity, while particle size has minimal impact on light absorption. Among hydrophobic agents, beeswax extract demonstrated superior performance, yielding apparent contact angles up to 130° and sliding angles of 8°. All coatings exhibited efficient light-to-heat conversion, with surface temperatures rising from 25 °C to over 45 °C within 3 min under simulated sunlight. BW coatings exhibited self-cleaning properties, as demonstrated by the removal of sand particles in a gentle water stream. The materials and processes used in this study are readily accessible and inexpensive. Compared to more complex fabrication methods, the approach is simple, scalable, and effective. These findings suggest that biogenic photothermal hydrophobic coatings offer promising potential for scalable, eco-friendly anti-icing solutions in practical applications.