Here reports a hollow cube NiCo2S4 nanomaterial, which was prepared via facile hydroxylation and sulfuration steps using the self-prepared ZIF-67 as a precursor. This kind of NiCo2S4 as an electrode material for supercapacitor presents a specific capacitance high up to 1350 F g-1 at 1 A g-1 due to the contribution of pseudocapacitance. Particularly, the hybrid supercapacitor PC//NiCo2S4, assembled using the NiCo2S4 as the positive electrode material and the PC as the negative electrode material, delivers a high energy density of 33 Wh kg-1 at the power density of 800 W kg-1. Meanwhile, it presents a good cyclic stability with 67% capacitance retention after 10,000 cycles of charge–discharge at the current density of 5 A g-1. However, the rate capability is not good enough because of the polarization effect of NiCo2S4 as a battery-type electrode material. Therefore, this research provides a reference for enhancing capacitance performance of an electrode material. For instance, reversibility in redox reaction and stability in structure are more important than the capacity in many cases.
Volume 132, 2020
Continuous Article Publishing mode
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