title: Nitrogen-Doped Carbon Membrane Derived from Polyimide as Free-Standing Electrodes for Flexible Supercapacitors.
abstract: Nitrogen-doped carbon materials have attracted great interest in the energy storage due to the better electrochemical performances than the pristine carbon materials. In this work, a heterocyclic polyimide containing benzopyrrole and benzimidazole rings is carbonized to fabricate the free-standing and flexible carbon membrane (CarbonPI ) with a high packing density (0.89 cm(-3)), in which the location of nitrogen atoms in the doped configurations is easily controlled. XPS analysis indicates that quaternary nitrogen is the predominant nitrogen-doped configurations. The high content of nitrogen effectively improves the wettability of the electrode materials. The CarbonPI membrane exhibits excellent volumetric capacitance (159.3 F cm(-3) at 1 A g(-1)), high rate capability (127.5 F cm(-3) at 7 A g(-1)), and long cycle life. TEM images reveal the very slight change of the microstructure of graphitic nanosheet of CarbonPI during the long charge/discharge cycles.
authors: State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, College of Materials Science and Engineering, Donghua University, Shanghai, 201620, P. R. China.
authors: Yingzhi
authors: Y
authors: Li
authors: State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, College of Materials Science and Engineering, Donghua University, Shanghai, 201620, P. R. China.
authors: Jie
authors: J
authors: Dong
authors: State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, College of Materials Science and Engineering, Donghua University, Shanghai, 201620, P. R. China.
authors: Junxian
authors: J
authors: Zhang
authors: State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, College of Materials Science and Engineering, Donghua University, Shanghai, 201620, P. R. China.
authors: Xin
authors: X
authors: Zhao
authors: State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, College of Materials Science and Engineering, Donghua University, Shanghai, 201620, P. R. China.
authors: Pingping
authors: P
authors: Yu
authors: State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, College of Materials Science and Engineering, Donghua University, Shanghai, 201620, P. R. China.
authors: Lei
authors: L
authors: Jin
authors: State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, College of Materials Science and Engineering, Donghua University, Shanghai, 201620, P. R. China.
authors: Qinghua
authors: Q
authors: Zhang
keywords: carbonization; free-standing structures; nitrogen doping; polyimides; supercapacitors