Rationally designed nanosheet-based CoMoO4–NiMoO4 nanotubes for high-performance electrochemical electrodes

Abstract

Ultrathin nanosheet-based CoMoO₄–NiMoO₄ nanotubes were designed and synthesized by a hydrothermal treatment. The nanotubes were composed of highly ordered ultrathin nanosheets. When used as electrodes in electrochemical capacitors, the nanosheet-based CoMoO₄–NiMoO₄ nanotubes demonstrated a high specific capacitance of 751 F g⁻¹ at a current density of 1 A g⁻¹ and good cycling ability with 94% initial specific capacitance retention after 2000 cycles. The electrode showed a high energy density of 30.86 W h kg⁻¹ at a specific power of 0.27 kW kg⁻¹ and still maintained the energy density of 16 W h kg⁻¹ at the power density of 4.85 kW kg⁻¹. The prominent electrochemical performances are attributed to the rational combination of two electroactive materials and the unique nanostructure of the nanotubes constructed by nanosheets that increases the rate of electrolyte diffusion and electron transport. The nanosheet-based CoMoO₄–NiMoO₄ nanotubes with remarkable electrochemical properties could be considered a prospective electrode material for the application of electrochemical capacitors.