Tailoring micro/nanostructured porous polytetrafluoroethylene surfaces for dual-reversible transition of wettability and transmittance

Materials with dynamic transition are current mostly limited to two-state transition of single property. Herein, a textured polytetrafluoroethylene (PTFE) film with hierarchical porous micro/nanostructures is fabricated by one-step femtosecond laser line-by-line scanning technology. The as-prepared sample is superhydrophobic and opaque, and its wettability and optical transmittance can be simultaneously controlled. As the sample prewetted with alcohol, it displayed superhydrophilicity with high transparency. In contrast, since the prewetted surface was dried, it recovered its original superhydrophobicity and opacity. The switching repeatability, applicability of solutions, stability of the samples are also demonstrated. By using its controllable switching performances, potential applications such light pass/block controlling, anti-fogging, cooling were realized on the as-prepared surfaces. This work reports a smart surface with dual-functional transition ability, which could open fresh ideas for a broad range of multifunctional applications.