Fabrication of Superhydrophobic Composite Membranes with Honeycomb Porous Structure for Oil/Water Separation

Due to the low separation efficiency and poor separation stability, traditional polymer filtration membranes are prone to be polluted and difficult to reuse in harsh environments. Herein, we reported a nanofibrous membrane with a honeycomb–like pore structure, which was prepared by electrospinning and electrospraying. During the electrospraying process, the addition of polydimethylsiloxane and fumed SiO2 formed pores by electrostatic repulsion between ions, thereby increasing the membrane flux, subsequently reducing the surface energy, and increasing the surface roughness. The results show that when the content of SiO2 reaches 1.5 wt%, an ultra–high hydrophobic angle (162.1° ± 0.7°) was reached. After 10 cycles of oil–water separation tests of the composite membrane, the oil–water separation flux and separation efficiency was still as high as 5400 L m−2 h−1 and 99.4%, and the membrane maintained excellent self–cleaning ability.