Gradient structure based dual-robust superhydrophobic surfaces with high-adhesive force

Dual-robust (mechanical and chemical robust) superhydrophobic surfaces with a high adhesive state have aroused lots of attention for their potential application in liquid transportation, biochemical separation and in situ detection devices. Herein, we design a gradient structure based multi-scale micro- and nano-structures (inorganic-organic interpenetrating structures, self-similar sacrificial structures and micro-nano structures) to realize dual robust superhydrophobic surfaces by spraying method. Upon changing the fabrication process, three kinds of superhydrophobic surfaces were made based on benzoxazine, mesoporous SiO ₂ and imidazole. A rigorous sandpaper abrasion test, chemical resistance test (pH = 1–14, 12 h) and anticorrosion test were carried out to exhibit the environmental stability of the system. High adhesive properties of surfaces were demonstrated by adhering water test. The clear multi-scale structures are showed and its relationship with properties is built. Scanning electron microscope was used to examine different structures and the gradient structure in system. The gradient structure based dual-robust superhydrophobic surfaces give a promising prospect for water transportation application in their large-scale and low-cost fabrication method and super mechanical and chemical robust.