Route to a Porous Carbon Nanofiber Membrane Containing Fe_xC_y/Fe by Facile In Situ Ion-Exchange Functionalization of the PAA Carboxyl Group: Exemplified by a Supercapacitor

Abstract

In this paper, the concept of facile carboxyl in situ ion-exchange (CISIE) functionalization is utilized in preparing polyimide (PI)-derived carbon materials for the first time. Taking Fe species as an example, a high-performance Fe x C y /Fe composite porous carbon nanofiber (PCF) membrane is obtained by electrospinning of the PI precursor. The morphology and structure are characterized by scanning electron microscopy, X-ray diffraction, Raman spectroscopy, X-ray photoelectron spectroscopy, and other means. Then, the electrochemical performance is taken as an example to highlight the prospect of this preparation method of functional porous carbon materials. The cyclic voltammetry curves are analyzed by means of b-values, Trasatti's method, and Dunn's method, and it was found that porous carbon materials can show pseudocapacitance due to the introduction of Fe 3+ . Herein, the activated PCF-Fe electrode exhibits a high specific capacitance, which reaches 340 F g −1 at a current density of 1 A g −1 and shows a rate capability of 35.29% (120 F g −1 at 50 A g −1 ). In addition, PCF-Fe also shows great potential for application in self-standing electrodes. Furthermore, an assembled asymmetric supercapacitor made of PCF-Fe exhibits an energy density of 16.3 W h kg −1 at a power density of 0.6 kW kg −1 and a long cycle life. The Fe x C y /Fe composite PCF membranes obtained based on facile CISIE functionalization exhibit an excellent electrochemical storage performance and are expected to be utilized as electrode materials for supercapacitors.

N-Doped carbon nanoparticles on highly porous carbon nanofiber electrodes for sodium ion batteries

“…Moreover, the deconvolution of N1s peaks showed that the compositions of pyridinic and pyrrolic are high which result in more conductive and reversible sites for Na + ion adsorption. 7,30 The amounts of graphitic-N (402.6 eV), pyrrolic-N (400.8 eV) and pyridinic-N (398.5 eV) are 1, 33, and 66%, respectively for N-PCNF4 whereas those are 26, 20 and 54% respectively for N-PCNF5 which confirms Raman results that suggest higher disordered structure of N-PCNF4.…”

Research Progress and Application of Polyimide-Based Nanocomposites

“…Lei et al [ 136 ] successfully prepared CeO 2 –Fe 2 O 3 –ZnO compound oxide layers on a PI substrate by this ion exchange scheme and studied the effects of different initial Ce, Fe, and Zn ion loadings on the microstructure, thermal properties, and catalytic performance of the obtained PI-supported mixed oxide, consequently achieving a superior methyl orange degradation rate of 98.7% in 12 min ( Figure 14 ). Researchers effectively synthesized a series of PI composites using an ion exchange method, such as silver/PI (Ag/PI), copper/PI (Cu/PI), zinc oxide/PI (ZnO/PI), iron/PI (Fe/PI) composites, and so on [ 137 , 138 , 139 , 140 ]. The main advantage of PI composites prepared by this technology is the well dispersibility, size adjusting, and morphology modification of metal and metal oxide nanoparticles to optimize the performance.…”

Exchanging interlayer anions in NiFe-LDHs nanosphere enables superior battery-type storage for high-rate aqueous hybrid supercapacitors

“…31,32 The interlayer spacing of LDHs can be enlarged by introducing macromolecules or organic molecules, such as aniline and sodium dodecyl benzene sulfonate (SDBS). [33][34][35] Additionally, the interlayer of the LDH structure also can be tuned by varying the concentration of the metallic ratio, temperature, and reaction time during the preparation. The most efficient way to tune the interlayer spacing is by exchanging the interlayered anions during the synthesis of materials.…”