Structural and Morphological Characterization of Graphene Oxide (GO), Reduced Graphene Oxide (rGO), and Nitrogen-Doped Graphene Oxide (N-GO) for Electrochemical Water Treatment

Abstract

Developing efficient electrode materials is essential for improving electrochemical water treatment technologies. In this study, we synthesized and compared three materials: graphene oxide (GO), reduced graphene oxide (rGO), and nitrogen-doped graphene oxide (N-GO). GO was produced using a modified Hummers method, followed by chemical reduction to obtain rGO and hydrothermal nitrogen doping to obtain N-GO. Scanning Electron Microscopy (SEM) showed clear morphological changes, evolving from the flat and exfoliated sheets of GO to the highly crumpled and porous three-dimensional structure of N-GO, which offers a larger surface area for contaminant adsorption. X-ray diffraction (XRD) confirmed an expanded interlayer spacing of about 0.86 nm in GO and the reappearance of the graphitic (002) peak near 25 degrees after reduction and nitrogen doping. Raman spectroscopy provided additional structural insights, showing a blue shift of the G band to around 1595 cm⁻¹ and an ID/IG ratio of 1.11 in N-GO, indicating successful nitrogen incorporation and the formation of active defect sites. These combined structural improvements, especially the restored conductivity and increased defect density in N-GO demonstrate its strong electrochemical potential for removing pollutants from water. This work offers a solid structural foundation for designing optimized graphene-based electrodes for high-performance water purification systems.