Mechanically robust superhydrophobic coating from sawdust particles and carbon soot for oil/water separation

We propose a facile, cost-effective and commercially viable method to prepare durable superhydrophobic surfaces using a bio-waste material. The naturally available nanostructured sawdust particles were combined with polychlroprene adhesive, carbon soot and silicon polymer to formulate superhydrophobic coatings. Saw dust particles were bonded on the substrate using polychloroprene adhesive, which was followed by depositing silicone by dip-coating to produce a superhydrophobic surface. To further improve the mechanical and superhdyrophobic properties, a thin layer of carbon soot was deposited and stabilized by second layer of silicone. Electron microscopy, spectroscopy and goniometry were employed for microstructural analysis, chemical nature and the contact angle measurements of the coatings. After quantifying the excellent response against mechanical abrasion, the superhydrophobic coating was employed on a mesh to demonstrate its application for oil/water separation. It was observed that the coated mesh successfully separated both light and heavy oils from oil/water mixtures with high separation efficiency and therefore has the potential for large-scale separation of oil/water mixtures.