Fabrication of Vanadium Oxide@Polypyyrole (V2O5@PPy) Core-shell Nanofiber Electrode for Supercapacitor

Abstract

To address the dissolution problem and further enhance the cycling stability and capacitive performance of V2O5, V2O5@polypyrrole (V2O5@PPy) core-shell nanofiber electrode was synthesized by combining a low-cost, easily processible, and eco-friendly sol-gel with in situ polymerization method in this work. V2O5@PPy showed a high specific capacitance of 307 F/g and good cycling life (82% capacity retention up to 1000 cycles). This benefited from the highly conductive PPy coating layer that facilitated charge transfer and protected the dissolution of V2O5 in the aqueous solution. The synergistic effect between V2O5 and PPy and the individual role of each component in the electrochemical process were studied to further explore the growth mechanism and provide some important guidance for the rational design of electrode materials in the future. Also, the two-electrode symmetric V2O5/PPy device exhibited a maximum energy density of 37 Wh/Kg when the power density was 161 W/kg.