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This study explores a simple method of fabricating hybrid supercapacitor electrodes, which could potentially broaden the application of this technology. The method involves electrospinning a uniform solution of Matrimid/Metal−Organic Polyhedra 18 (MOP−18) followed by carbonization at a relatively low temperature of 700 °C in air, rather than in an inert atmosphere, to create free−standing, redox−active hybrid supercapacitor electrodes. Additionally, the synthesis procedure requires no stabilization or activation steps, which enhances the cost effectiveness of the synthesized electrode materials. The resulting C/CuO composite was used as the working electrode, with a polyacrylonitrile (PAN)/Poly(methyl methacrylate) (PMMA) carbon nanofiber (CNF) electrode as the counter and 6 M KOH as the electrolyte in a T−cell configuration. The cell performance and redox activity were evaluated using cyclic voltammetry (CV), galvanostatic charge–discharge (GCD), electrochemical impedance spectroscopy (EIS) and cycling stability tests. Additionally, the physical and chemical structures of the electrode materials were assessed using X−ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), transmission electron spectroscopy (TEM), X−ray diffractometry (PXRD), surface area analysis and other characterization techniques. The electrode material demonstrated a specific capacitance of up to 206 F/g. Supercapacitors utilizing this material display an energy density of 10.3 Wh/kg (active material) at a current density of 1 A/g in electrochemical testing. [ABSTRACT FROM AUTHOR]

Vanadium sesquioxide/vanadium nitride nanoparticles were prepared in carbon fibers by electrospinning, followed by carbonization. Polyacrylonitrile was used as the carbon precursor, poly-(methyl methacrylate) as the porogen, and V2O5 nanowires as the vanadium source. During the high temperature carbonization, V2O5 was reduced in situ by carbon and converted into V2O3 and further transformed into VN by NH3 released from polyacrylonitrile. The composite was used as electrodes and fabricated into a symmetric coin cell-type supercapacitor using 1 M lithium bis-(trifluoromethanesulfonyl)-imide in propylene carbonate as the electrolyte. The resulting supercapacitor showed a specific capacitance of 369 F g–1 at 5 mV/s, an energy density of 107 Wh kg–1 at 0.05 A g–1, and a high power density of 5154 W kg–1 at 5 A g–1. [ABSTRACT FROM AUTHOR]

The process pf electrospinning, which produces fibers in the nanometer to micron range under the influence of high voltages, is studied to produce polymer and textile fibers. The electroluminescent polymer MEH-PPV and molecular sieve SBA-15 is used to produce the composite fibers and an inte4seting aspect of these composites is that the fluorescence of MEH-PPV is blue shifted in the composites.

The standard heterogeneous electron-transfer rate constants between substrate gold electrodes and either ferrocene or pentaaminepyridine ruthenium redox couples attached to the electrode surface by various lengths, which are measured as a function of temperature are presented.