A coactive performance of Ag2WO4 nanorods wreathed on the N-doped carbon nanofibers as electrode for electrochemical supercapacitors

Abstract

The thriving energy demand of the gradually increasing population and modernised life style requires development in energy storage devices for usage in commercial electronic devices. In this particular work, we have explored electrochemical performances of bimetallic oxide Ag2WO4 nanorods and tuned its performance by decorating it on the nitrogen doped carbon nanofiber (N-CNF). The Ag2WO4 nanorods are synthesised by a facile route of co-precipitation method followed by ultrasonication with N-CNF. The synthesised Ag2WO4 nanorods was found electrochemically active and the incorporation of N-CNF end up boosting its electrochemical performances. The obtained nanocomposites were characterised by various advanced techniques. The amount of N-CNF was determined by characterisation via the potentiostatic and galvanostatic cycle measurements and electrochemical impedance spectroscopy (EIS). The electrochemically active Ag2WO4 with 20 wt. % of N-CNF (Ag2WO4/N-CNFb) exhibited 2.2-fold higher charge storage capacity than pristine Ag2WO4. The Ag2WO4/N-CNFb exhibited specific capacitance as high as 330 F g-1 at a constant applied current density of 1 A g-1 in 1 M KOH. The improved capacity may be due to conductive pathways provided by N-CNF. The Ag2WO4 got well decorated over the N-CNF facilitating the active sites interaction with electrolyte. The symmetric device fabricated with Ag2WO4/N-CNFb electrodes exhibited excellent energy density of 10 W h kg-1 at 6000 W kg-1 at 5 A g-1. The Ag2WO4/N-CNFb electrode long-term stability has been minutely observed; the high Coulombic efficiency of 90% and high rate of capacity retention 98% even after 3000 cycles. Owing to these excellent electrochemical properties, the research work can potentially widen the opportunity to explore other profound bimetallic oxides and its nanocomposites with conductive carbon-based matrix for energy storage applications.