Synthesis and characterization of N-doped reduced graphene oxide for the supercapacitor application

Abstract

In this work, N-rGO is synthesized as a material for the electrode of supercapacitors using a single-stage hydrothermal process. Ammonia functions as a nitrogen source and a reducing agent, significantly enhancing its electrochemical properties. X-ray diffractometry (XRD), Raman spectroscopy, field emission gun scanning electron microscopy (FESEM), and FT-IR (Fourier-transform infrared spectroscopy) were employed for characterization of as-prepared N-rGO electrodes. The XRD plot evidences the successful reduction of as-received GO to as-prepared N-rGO. The FESEM micrograph displays the formation of highly porous and multi-layered N-rGO, showcasing significant structural characteristics. The nitrogen atoms are successfully incorporated into the resulting material (N-rGO) and have been verified through EDS and FT-IR spectroscopy studies. The specific capacitance of N-rGO reaches 107 Fg?1 at 0.5 Ag?1 in a 0.5 M H<inf>2</inf>SO<inf>4</inf> aqueous electrolyte solution. The electrodes showed exceptional cyclic performance, maintaining approximately 130% capacitance after 10,000 cycles and delivering steady Coulombic efficiency. The material's porous structure and nitrogen doping create abundant active sites, facilitating electrolyte ion migration and producing exceptional capacitive performance. The electrochemical impedance spectroscopy study revealed that the N-rGO exhibited a distinctive capacitive behavior. The synthesized N-rGO offers excellent potential for an efficient energy storage application due to its simple, cost-effective, and eco-friendly approach. © The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature 2025.