Supercapacitor device performances of polycarbazole/graphene and polycarbazole/nanoclay/graphene nanocomposites

Abstract

In this study, graphene oxide (GO) is chemically reacted with sodium borohydride (NaBH4) to form reduced graphene oxide (rGO). rGO, polycarbazole (PCz)/rGO and PCz/nanoclay/rGO materials were obtained by chemical polymerisation method. These three materials were characterised by Fourier-transform infra-red spectroscopy-attenuated transmission reflectance, scanning electron microscopy, energy-dispersive X-ray analysis, cyclic voltammetry (CV), galvanostatic charge-discharge and electrochemical impedance spectroscopy. The PCz/nanoclay/rGO nanocomposite shows significantly improved capacitance (C-sp = 187.78 Fg(-1)) compared to that of PCz/rGO (C-sp = 74.18 Fg(-1)) and rGO (C-sp = 20.78 Fg(-1)) at the scan rate of 10 mVs(-1) by CV method. The supercapacitor device performance results show high power density (P = 1057.81 Wkg(-1)) and energy density (E = 1.7 Whkg(-1)) obtained from Ragone plot for PCz/nanoclay/rGO material. Stability tests were also examined by the CV method for 1000 cycles.