Durable self-cleaning hydrophobic surface of hollow cylindrical stainless steel with controllable adhesion prepared by nanosecond laser

The easy preparation of an environmentally friendly self-cleaning functional surface has been a troubling challenge that limits the effort put in by current researchers to achieve production and application of target materials. In this paper, a hollow cylindrical stainless-steel superhydrophobic surface (HCSS) is developed. Based on the nanosecond laser processing method, a hollow cylindrical microstructure is designed on the metal surface, and low surface energy treatment is completed by secondary scanning after stearic acid immersion, which can achieve low adhesion to a variety of liquids and universal applicability to a variety of metal materials and application scenarios. The results show that the HCSS has a smaller solid-liquid contact area and the hollow structure forms an air cushion layer, which greatly enhances the wettability of the metal surface. Moreover, adjusting the height of the air cushion using the negative pressure principle can clearly show the controllability of surface adhesion. The hollow cylindrical microstructure surface prepared by the eco-friendly and non-toxic method has excellent performance in low adhesion and self-cleaning durability.