Vanadium Sesquioxide/Nitride Nanostructures in Electrospun Carbon Fibers for High Energy Density Supercapacitors

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.