Synthesis of Co3O4@CoMoO4 core-shell architectures nanocomposites as high-performance supercapacitor electrode

- High specific capacitance of Co3O4 was attributed to highly accessible surface area.
- Co3O4@CoMoO4 nanocomposites showed excellent capacitive performance.
- CoMoO4 nanorods induced high specific capacitance and outstanding stability.

3D Co3O4@CoMoO4 core-shell architectures directly grown on nickel foam for supercapacitor electrode were obtained by two-step hydrothermal process. The Co3O4@CoMoO4 nanocomposites electrode exhibited higher capacitance than Co3O4 nanowire electrode. Maximum specific capacitance of 2530 F g− 1 was obtained at current density of 1 A g− 1 for Co3O4@CoMoO4 core-shell architectures. In addition, after 3000 cycles of continuous galvanostatic charge-discharge cycles, only about 3.7% degradation in specific capacitance could be noticed. The CoMoO4 nanorods stack on Co3O4 nanowires arrays allowed facile electrolyte movement during charge or discharge process and provided more active sites for the electrochemical reactions. The unique architecture had a large interfacial area and numerous channels for rapid diffusion of electrolyte ions and fast electron transport. In addition, the synergetic effect between Co3O4 nanowire and CoMoO4 nanorods also improved the supercapacitor performance.