Synthesis and characterization of graphene oxide using a modified Hummers method for enhanced quality and yield

Graphene oxide (GO) was successfully synthesized using a modified Hummers method and comprehensively characterized to confirm its structural, morphological and optical properties. Compared to earlier synthesis techniques, the modified method offers enhanced safety, reproducibility and a higher degree of oxidation. Ultraviolet-visible spectroscopy, Fourier-transform infrared spectroscopy and X-ray diffraction analyses confirmed the incorporation of oxygen-containing functional groups and the structural transformation from graphite to GO. Raman spectroscopy indicated significant structural disorder and the formation of sp2/sp³ hybrid domains. Scanning electron microscope and Transmission electron microscope analyses revealed the typical layered morphology of GO, while energy dispersive X-ray spectroscopy confirmed its elemental composition and high oxidation state. Optical and photoluminescence studies further supported the presence of disrupted conjugation and oxygenated functionalities. The synthesized GO exhibited a C:O ratio of 1.82, an optical bandgap in the range of ∼2.5–3.6 eV and a disorder index (ID/IG) of 0.93, aligning well with values reported in the literature. These findings demonstrate that the modified Hummers’ method is a reliable, scalable and efficient approach for producing high-quality GO, suitable for a broad range of applications, including energy storage, water treatment and nanoelectronics.