Synthesis of hierarchical carbon sphere@NiMoO₄ composite materials for supercapacitor electrodes

In this work, hierarchical Carbon sphere@NiMoO₄ (C@NiMoO₄) composite was successfully synthesized by cost-effective two-step hydrothermal method. The samples were characterized by scanning electron microscopy, X-ray photoelectron spectroscopy, X-ray diffraction analysis and Thermogravimetric analysis. The Electrochemical measurement demonstrated that hierarchical C@NiMoO₄ electrode materials exhibited good specific capacitance (Csp) of 268.8 F g⁻¹ at a current density of 1 A g⁻¹ in 2 M NaOH aqueous electrolyte solution, as well as good cycling stability (88.4% retention after 2000 cycles). Compared to pure NiMoO₄, the excellent capacitive properties and stability suggest that the hierarchical structure C@NiMoO₄ could be promising electroactive material for supercapacitors.