Hydrophobic polyacrylonitrile/pitch electrospun nanofibers for oil spill cleanup: Fabrication, optimization, and kinetic investigations

Superhydrophobic surfaces are of immense scientific and technological interests for a broad range of applications. However, a major challenge remains in developing scalable methodologies that enable superhydrophobic coatings on versatile substrates with a combination of strong mechanical stability, optical transparency, and even stretchability. Herein, we developed a scalable methodology to versatile hydrophobic surfaces that combine with strong mechanical stability, optical transparency, and stretchability by using a self-assembled hydrogel as the template to in situ generate silica microstructures and subsequent silanization. The superhydrophobic coatings can be enabled on virtually any substrates via large-area deposition techniques like dip coating. Transparent surfaces with optical transmittance as high as 98% were obtained. Moreover, the coatings exhibit superior mechanical flexibility and robustness that it can sustain contact angles ∼ 160° even after 5000 cycles of mechanically stretching at 100% strain. The multifunctional surfaces can be used as screen filters and sponges for the oil/water separation that can selectively absorb oils up to 40× their weight.