The synthesis of rGO, rGO/RuO2 and rGO/RuO2/PVK nanocomposites, and their supercapacitors

In this study, graphene oxide (GO) was eco-friendly and reduced with microwave-assisted method to form reduced graphene oxide (rGO). Two components of nanocomposite of rGO and Ruthenium oxide (RuO2) (rGO/RuO2) and a ternary components of nanocomposite of rGO, RuO2 and polyvinylcarbazole (PVK) (rGO/RuO2/PVK) were synthesized via in-situ polymerization technique. These nanocomposite materials were characterized by Fourier-transform infrared spectroscopy-attenuated transmission reflectance (FTIR-ATR), scanning electron microscopy (SEM), and energy-dispersive X-ray analysis (EDX), thermal-gravimetric (TGA-DTA) analysis, transmission electron microscopy (TEM), X-ray diffraction (XRD), and BET surface analysis. Supercapacitor device performances were taken by cyclic voltammetry (CV), galvanostatic charge/discharge (GCD), and electrochemical impedance spectroscopy (EIS) used as two electrode configuration. The highest specific capacitance (C-sp) was obtained as C-sp = 2698 F/g at 2 mV/s for rGO/RuO2/PVK nanocomposite at initial feed ratio of [rGO](o)/[RuO2](o)/[9-VK](o) = 1: 1: 5. Besides, the highest energy and power density values were obtained as E = 17.711 Wh/kg and P = 2684.36 W/kg for rGO/RuO2 nanocomposite. Ragone plots were drawn to observe energy and power density of supercapacitor devices. Stability tests were examined by CV method for 1000 cycle. (C) 2019 Elsevier B.V. All rights reserved.