First investigation of high-performance FeS-based W18O49 asymmetric supercapacitors operating at 1.6 V

Abstract

This study presents a comprehensive evaluation of FeS-W18O49 composite electrodes, revealing their exceptional performance for supercapacitor applications. Fabricated via a wet-chemical method, the FeS-W18O49 composites demonstrated a high specific capacitance of 558 F g−1 at a current density of 1 A g−1, showcasing their outstanding charge storage capabilities. The composites achieved an energy density of 89.77 W h kg−1 and a power density of 4950 W kg−1, attributed to the synergistic effect between the excellent electrical conductivity of FeS and the redox activity of W18O49, which collectively enhance the electrode's electrochemical performance. Moreover, the FeS-W18O49 electrodes exhibited remarkable cycling stability, retaining 87.6% of their capacitance after 10 000 charge-discharge cycles. These findings underscore the potential of FeS-W18O49 composites to advance supercapacitor technology by improving energy storage capacity and extending cycle life.