Long-time durability of superhydrophobic surface fabricated by laser texturing and carbon soot

In this work, a novel approach to fabricate highly durable superhydrophobic surfaces (SHSs) with exceptional long-term performance. The demand for real-world applications in various areas such as self-cleaning, anti-bacterial, anti-icing, and water droplet non-wetting behaviour has driven significant attention towards SHSs fabrication. As inspired by the lotus leaf's hierarchical structure, which combines low surface energy and a micro/nanopillar structure to achieve Superhydrophobicity. To achieve this, a fibre laser marking machine has been used to create circular-shaped microstructures on an AISI 420 steel substrate, with a pitch and diameter of 100 µm. To further enhance the surface's water-repellent properties, a unique technique that involves the deposition of carbon soot onto the textured geometry using a candle has been adopted. This resulted in a surface with impressively low surface energy. The most notable aspect of our research is the long-term durability of the fabricated SHSs. Even after two years of exposure to ambient conditions, the surface maintained a maximum contact angle of 158.6°, which is remarkably high, exceeding 150°. This research shows a robust and enduring superhydrophobic surface fabrication method, highlighting its potential for diverse real-world applications.