ZIF-67 Derived Co3S4/WO3 Composites as a Negative Electrode for Hybrid Supercapacitor Application

Abstract

The new approach to synthesize porous Co3S4 nanoparticles derived from ZIF-67 polyhedrons decorated with WO3 rectangular sheets is demonstrated. Furthermore, the composite material is employed as a negative electrode for high energy density supercapacitor application. The one pot hydrothermal treatment of ZIF-67 with WO3 precursor give the Co3S4/WO3 composites. The obtained samples are evaluated with cyclic voltammetry, galvanostatic charge/discharge and electrochemical impedance spectroscopy tests. The composites delivered the highest specific capacitance of 668 F/g at the current density of 1 A/g in 1 M H2 SO4 electrolyte. Addition to this, the composite material remains stable upto 2000 cycles of charging/discharging cycles with 94% capacitance retention. The excellent electrochemical performance is attributed to the synergy between the sheet like WO3 structure and Co3S4 nanoparticles. The positive electrochemical results of the composites demonstrate its potential or practical hybrid supercapacitor application.