The synergistic effect of the RuO2 nanoparticle-decorated V2O5 heterostructure for high-performance asymmetric supercapacitors

Abstract

Two-dimensional RuO₂ nanoparticle-decorated V₂O₅ nanoflakes are successfully synthesized by a simple solvothermal method. The synthesized RuO₂-decorated V₂O₅ nanocomposite electrode exhibited a high charge–discharge capacity with an excellent cyclic retention of 94.6% over 10 000 cycles. Specifically, the 3 wt% RuO₂ in V₂O₅ (R2) nanocomposite electrode showed a high specific capacitance of 421 F g⁻¹ at a current density of 1 A g⁻¹ in a three-electrode system. The specific capacitance of the R2 nanocomposite is almost 3-fold higher than that of pure V₂O₅ nanosheets in the three-electrode system. An energy density of 29 Wh kg⁻¹ was achieved in a two-electrode system at a power density of 816 W kg⁻¹ in an R2 based asymmetric supercapacitor device. The energy density and power density of the RuO₂–V₂O₅ nanocomposite are higher than those of previously reported V₂O₅ nanostructured asymmetric supercapacitors.