Hierarchical porous nitrogen-doped carbon nanofiber (HPNCNF) films were prepared via a simple electrospinning process, in which polyacrylonitrile and silicone surfactants were adopted as carbon source and porogen, respectively, followed by a thermal treatment. The morphology, chemical composition, and porosity of the HPNCNF5 were investigated by scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, Raman spectroscopy and nitrogen adsorption-desorption experiments. The as-prepared HPNCNFs with a specific surface area of 656 m(2) g(-1), a hierarchical pore structure, and a nitrogen content of 8.1 at% showed a specific capacitance of 289 F g(-1) in a 6 mol L-1 KOH aqueous solution with excellent cycle durability, making HPNCNF films a promising electrode material for a future application in supercapacitors. (C) 2015 Elsevier B.V. All rights reserved.