Enhanced faradaic pseudo-capacitance in a reduced π-conjugated carbon network anchored with strontium tungstate nano-hybrids for high-energy supercapacitors

Abstract

The development of high-performance electrode materials is essential for next-generation supercapacitor (SC) technologies. Herein, SrWO₄/rGO hybrid nanostructures were synthesized to enhance electrochemical performance through the synergistic effect of conductive SrWO₄ and high-surface-area reduced graphene oxide (rGO). The hybrid electrode exhibits excellent electrochemical performance, delivering an excellent specific capacitance of 727 F g⁻¹ at 1 A g⁻¹ and retaining 95% of its capacitance over 5000 cycles, indicating long-term stability. The assembled symmetric two-electrode cell (SrWO₄/rGO@NF//SrWO₄/rGO@NF) operates within a 1.6 V potential window in 1 M KOH electrolyte and shows excellent rate capability. Electrochemical impedance spectroscopy of a symmetric cell reveals low charge-transfer resistance and efficient ion diffusion. The Ragone plot indicates an impressive energy density of 26.13 Wh kg⁻¹ at a power density of 2159.5 W kg⁻¹ for the assembled symmetric cell. This exceptional performance is attributed to the synergistic effects of conductive SrWO₄ and the higher surface area of the resorted π-conjugated rGO structure, enabling efficient charge transport and abundant electroactive sites. These results highlight a promising strategy for developing advanced electrode materials for high-performance energy storage systems.