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

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.