Design and construction of hollow nanocube NiMoO4 electrode with high performance for asymmetric supercapacitor.

In this work, NiMoO₄ hollow nanocubes were first successfully obtained via facile solvothermal and subsequent etching process. Assembling two-dimensional NiMoO₄ nanosheets into the three-dimensional framework based on Cu₂O nanocubes provided outstanding nanostructure stability and excellent electrochemical property. For example, the as-prepared hollow NiMoO₄ nanocubes exhibited an outstanding capacitance of 1093 F g⁻¹ at 1 A g⁻¹. In addition, the supercapacitor is composed of hollow NiMoO₄ nanocubes as positive electrode and N-rGO as negative electrode, which showed an outstanding energy density (44.01 Wh kg⁻¹) at a power density of 769 W kg⁻¹ in a voltage windows of 0–1.55 V, and even maintained an energy density (23.68 Wh kg⁻¹) at a high power density (7.7 kW kg⁻¹). Furthermore, the device delivered a promising long-term cyclic performance of 84.7% capacitance retention after 5000 charge–discharge cycles. [ABSTRACT FROM AUTHOR]