Polyacrylonitrile/polypyrrole core/shell nanofiber mat for the removal of hexavalent chromium from aqueous solution

► PAN nanofibers obtained by electrospinning. ► PAN/PPy core/shell nanofiber membrane was prepared. ► PAN/PPy core/shell nanofiber membrane used for Cr(VI) removal. ► Adsorption capacity remained up to 80% within 5 times cycles.