Construction of superhydrophilic hierarchical polyacrylonitrile nanofiber membranes by in situ asymmetry engineering for unprecedently ultrafast oil–water emulsion separation

With multi-hydrophilic functional networks, asymmetric PAN nanofiber membranes with finely tailored pore structures and hydrophilicity are constructed and show high permeance 22 000 L m⁻² h⁻¹ bar⁻¹, separation efficiency 99.2% and flux recovery rate 98%.