Nanoscale Bumps and Dents on Nanofibers Enabling Sonication-Responsive Wetting and Improved Moisture Collection

Nanofibers have been developed as basic nanotechnology building blocks, however, unlike with conventional textiles, nanofibers have lacked the surface engineering tools. Herein, we have developed novel basic techniques used to introduce nanoscale bumps and dents on the surfaces of nanofibers. Nanoparticles were first attached uniformly onto nanofibers by electrohydrodynamic jetting, which were subsequently thermally annealed to embed the nanoparticles (bumps). The embedded nanoparticles could be further detached via ultrasonication, resulting in the formation of nano-craters (dents). Ultrasonication could change the contact angle of nanofibers in situ from 84 degrees to 146 degrees. These surface nanoengineering techniques could widen the utility window of nanofibers.