Fabrication of hybrid micro-nano structure superhydrophobic surfaces by a simple nanosecond laser ablation and chemical modification process

The present study describes a simple method for fabricating hybrid micro-nano structured super-wetting surfaces of copper oxide using the laser ablation. Laser ablation technology enables the replication the surface arrays featuring peak-groove surfaces, stacked particles, and oxidation of copper in a single step. Copper oxide coats the surfaces of the microstructures. The resulting Cu samples exhibit excellent non-wetting properties following chemical modification with stearic acid. The water contact angles (WCAs) of the laser-ablated samples were measured at 156.9° with an average roughness value of 10.0 μm on a rough hybrid micro-nano structure, for samples treated with a Q-switched laser pulse duration of 0.30 μs＀ Furthermore, accompanied by self-cleaning and anti-fouling properties, the hybrid structure can maintain droplets in a superhydrophobic state for an extended duration during evaporation. Even after exposure to mechanical wear, acids, and alkalis, the surface remains its superhydrophobic properties. This paper presents a detailed study of the surface topology, elemental composition, the roughness, and the wetting properties. The vital outcome of this study is the development of hybrid micro-nano structures in a single step, fabricated using straightforward laser ablation process.