Durable tetra-scale superhydrophobic coatings with virus-like nanoparticles for oil-water separations

For highly efficient water-oil separation, superhydrophobic surfaces were prepared by coating the virus-like silica nanoparticles (VLSNs) on a substrate in scalable manner and subsequent fluoroalkyl silane through the sol-gel process. On the VLSN-coated glass substrate, the contact angle of the water droplet increased from 100.8 degrees (plain silica nanoparticles) to 178.9 degrees in the air as the areal density of coated nanoparticles increased up to 8,170 nanoparticles per mu m2. Furthermore, fabric membrane and stainless-steel mesh were coated with VLSNs and subsequently functionalized with fluoroalkyl silane, which was utilized for continuous oil-water separation with a high separation efficiency (>99%), high flux (>2,000 L/m2h) and high washing durability (>500 cycles). Additionally, these superhydrophobic fabrics were applied for removing oil contaminants on water by absorption within ten seconds.

Automated summary

Researchers successfully prepared superhydrophobic surfaces using the sol-gel process for highly efficient water-oil separation and oil contaminant removal. By coating virus-like silica nanoparticles and fluoroalkyl silane on substrates, they achieved high separation efficiency, high flux, and washing durability for oil-water separation.