Nanosecond laser fabrication of microporous silver for superhydrophobicity with wetting simulation mechanisms

Laser microfabrication is used to create micro/nano structures on surfaces to enhance hydrophobicity. In this study, nanosecond laser irradiation was employed to prepare microporous structures on silver surfaces. The topography of microstructures was controlled by adjusting laser power, scanning speed, repetition frequency, and number of scan passes, which further affected the wettability of the surfaces. The average optimal contact angles of four sample sets were 156.1°, 153.3°, 150.9°, and 147.2°, respectively. After silanization treatment, the average contact angles of laser-processed surfaces further increased to 161.0°, 157.5°, 158.2°, and 153.6°, all surpassing the threshold of superhydrophobicity. Furthermore, the numerical simulations and experimental analyses revealed that the droplet–surface contact area was affected by air filling inside the microporous structure, thereby critically governing wettability. The nanosecond laser strategy proposed in this work establishes a cost-efficient and scalable approach for manufacturing superhydrophobic precious metal surfaces, offering a promising industrial alternative to conventional surface modification techniques.