Influence of heat-treatment temperature on the improvement of the electrochemical performance of CoMoO₄ nanomaterials for hybrid supercapacitor application

The rational design and construction of nanostructured materials have a great impact on the development of high-performance advanced electrode materials, which has attracted extensive attention to improve reliable and efficient energy storage devices. Herein, we report vertically aligned CoMoO₄ nanoflakes with interconnected network-like porous structures as Faradic battery-type electrode materials for the advancement of supercapacitors (SCs). The nanoarchitecture CoMoO₄ electrode materials were effectively fabricated through simple hydrothermal method and subsequent heat-treatment under different temperatures. Further, the effect of heat-treatment on the electrodes materials’ structural, morphological, and electrochemical properties were investigated by utilizing various characterization techniques. The unique nanoarchitecture of the 400 °C heat-treated CoMoO₄ (CMO1) endows a facile pathway for the fast diffusion of the electrolyte ions and mass transfer reaction. Interestingly, the CMO1 (400 °C) electrode exhibits the specific capacity of 499 C g⁻¹, which is higher than those of the CMO2 (500 °C) of 385 C g⁻¹ and CMO3 (600 °C) of 260 C g⁻¹, respectively. Furthermore, the hybrid supercapacitor (HSC) tailored with CMO1 as a positrode and activated carbon as a negatrode delivers a high specific capacitance of 102 F g⁻¹ with excellent energy and power densities of 31.61 W h kg⁻¹ and 19.29 kW kg⁻¹, respectively.