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

Abstract

The new approach to synthesize porous Co 3 S 4 nanoparticles derived from ZIF-67 polyhedrons decorated with WO 3 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 WO 3 precursor give the Co 3 S 4 /WO 3 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 H 2 SO 4 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 WO 3 structure and Co 3 S 4 nanoparticles. The positive electrochemical results of the composites demonstrate its potential or practical hybrid supercapacitor application.