A Simple Way to Achieve Superhydrophobic Surfaces with Tunable Water Adhesion by a Nanosecond Pulse Laser

Superhydrophobic surfaces with various levels of adhesion have attracted tremendous research attentions due to their potential applications in both academic research and industrial application. Herein, we proposed a rapid and simple method to realize superhydrophobic surfaces with tunable water adhesion by nanosecond pulse laser irradiation on PTFE. The surfaces were composed of nanoscale and microscale square array. By only adjusting the power of the laser scanning, the adhesive forces between the water droplets and the as-prepared PTFE surfaces could be dynamically tuned. The tunable water adhesion was mainly ascribed to the change of micro/nano structure on the as-prepared surfaces which resulted from the change laser power. The as-prepared superhydrophobic surfaces showed tunable water adhesion from ultralow to ultrahigh, on which the static contact angle (SCA) of up to 155.2 1.5, and the sliding angle (CA) can be controlled from 3 +/- 0.5 degrees to > 90 degrees. The tunable adhesive surperhydrophobic surfaces could be achieved by a fast laser scanning speed. Compared with the other laser equipment, the 355nm nanosecond pulse laser had a high single photon energy, high processing speed, low equipment cost and maintenance cost, and showed a huge potential in industrial applications for large-scale fabrication of superhydrophobic surfaces.