Preparation of oil-water separation network based on the novel strategies of SiO2 ceramic micro-nano structure and PDMS modification

In this study, we adopted the novel strategies of the soot template method to construct SiO2 ceramic micro-nano structure surface and polydimethylsiloxane (PDMS) modification to reduce the surface energy. We fabricated a superhydrophobic/superoleophilic NS-PDMS oil-water separation screen by depositing coarse nano-SiO2 ceramic on the surface of 100-mesh stainless-steel screen used as a substrate under the soot template method, which reduced the surface energy with PDMS. The fabricated NS-PDMS screen exhibited excellent superhydrophobic and self-cleaning properties. In particular, the superhydrophobic properties were stably maintained under various harsh conditions. Overall, the screen manifested self-cleaning ability for various water-containing stains, for example, coffee, milk, beer, and soy sauce. The mechanically damaged screen surface still retained its high roughness, and re-modification with PDMS could recover the superhydrophobic surface and oil-water separation performance. This suggests the re-use potential of the damaged NS-PDMS screen, which is vital for cost reduction and resource recycling. We believe that our study makes a significant contribution to the literature, because the fabricated NS-PDMS screen is superhydrophobic, superoleophilic, resistant toward several water-based solutions, chemically and mechanically stable under certain conditions, and can be reused with modification and repair after damage. Therefore, this screen can be broadly used as an oil-water separator.