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

Abstract

ABSTRACTIn 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 (Csp = 187.78 F g−1) compared to that of PCz/rGO (Csp = 74.18 F g−1) and rGO (Csp = 20.78 F g−1) at the scan rate of 10 mV s−1 by CV method. The supercapacitor device performance results show high power density (P = 1057.81 W kg−1) and energy density (E = 1.7 Wh kg−1) obtained from Ragone plot for PCz/nanoclay/rGO material. Stability tests were also examined by the CV method for 1000 cycles.