Tannin-inspired robust fabrication of superwettability membranes for highly efficient separation of oil-in-water emulsions and immiscible oil/water mixtures

•Hydrophobic PVDF membrane was directly transformed into superhydrophilic ones.•The TA modified membrane possessed excellent water flux and separation efficiency.•The TA modified membrane displayed good recyclability and chemical stability.•This TA coating method can be applied on different kinds of substrate materials.