Influence of reduction duration on reduced graphene oxide for supercapacitor energy storage enhancement

Abstract

Reduced graphene oxide (rGO) has attracted significant attention in carbon-based energy storage devices due to its promising electrochemical properties. The performance of reduced graphene oxide (rGO) in supercapacitor energy storage devices is remarkably influenced by the duration of its reduction process. In this study, graphene oxide (GO) synthesized via a modified Hummer’s method and systematically reduced over varying durations to investigate the impact of reduction time on the structural and electrochemical properties of rGO. The reduction process was monitored using ex-situ X-ray diffraction (XRD), Raman spectroscopy, and High-resolution Transmission Electron Microscopy (HR-TEM) to gain detailed insights into the evolution of rGO over time. Structural analyses employing XRD, Fourier-transform infrared spectroscopy (FTIR), and Raman spectroscopy revealed that prolonged reduction led to increase crystallite size, decrease interlayer spacing, and reduced defect densities. Cyclic voltammetry measurements demonstrated a direct correlation between reduction duration and specific capacitance, with longer reduction times enhancing the energy storage performance of rGO. These findings, including Electrochemical Impedance Spectroscopy (EIS), underscore the critical influence of reduction duration on optimizing rGO for supercapacitor applications.