Flower-like CoMoO₄/Carbon Nanocomposites for Supercapacitors

Abstract

The synthesis and preparation of supercapacitor cathode materials is one of the important ways to achieve the increase of the energy density of supercapacitors. CoMoO 4 is a commonly used cathode material, but its own conductivity is poor, however, carbon can make up for this shortcoming of poor conductivity. In this paper, soluble starch with high solubility and uniform dispersion was used as the carbon source, and CoMoO 4 /carbon flower-like nanocomposites (CCMO) containing surface flocculants were successfully synthesized by a two-step hydrothermal reaction and applied as the cathode for supercapacitors, which showed excellent electrochemical properties. In order to determine the electrochemical properties of the prepared CCMO, it was tested in a three-electrode system. The test results demonstrate that the CCMO-3 electrode prepared under the condition of a quality ratio of CoMoO 4 to soluble starch of 1:1 demonstrated the best electrochemical performance, with a specific capacitance of 415F g –1 . After 15000 cycles at a current density of 10 A g –1, its specific capacitance remained at 87.5% of the initial reversible capacity. The supercapacitor device (CCMO//AC ASC) prepared with CCMO-3 and activated carbon, as both positive and negative electrodes, has an energy density of 12.44 Wh kg –1 under a power density of 799.71 W kg –1 . At a current density of 5 A g –1, it maintains 75% of its initial capacity after 10000 cycles. The excellent electrochemical performance of CCMO-3 shows its application potential in energy storage devices.