Ultradurable underwater superoleophobic surfaces obtained by vapor-synthesized layered polymer nanocoatings for highly efficient oil-water separation

Layered polymer nanocoatings consisting of a reactive polyisocyanate primer and grafted functional top were synthesized by single-step vapor phase polymerization deposition. The rationally designed coating architecture enables strong coating adhesion and highly enriched surface functionality, resulting in superhydrophilic and underwater superoleophobic surfaces with unprecedented durability. With a coating thickness as thin as 130 nm, the coated wool fabric exhibits an excellent oil-water separation efficiency above 99.99%, which is maintained after a series of harsh durability tests, including washing and abrasion against sandpaper for up to 150 cycles. The layered nanocoating is applicable to substrates regardless of their geometry, including highly porous fabrics for ultrafast free oil-water separation and microporous PVDF membranes for efficient gravity-driven oil-in-water emulsion separation.