Effect of Sulfur and Nitrogen co-Doped Graphene Quantum Dots on Co₃O₄ Nanoparticles as Solar Induced Photocatalyst

The photocatalyst process is considered the most promising method for the removal of water contamination. For excellent chemical and structural properties of Co₃O₄ nanoparticles, various Co₃O₄-based nanostructures can be applied as a photocatalyst. In this work, carbon quantum dots is prepared via an eco-friendly process and linked to Co₃O₄ effectively. X-ray diffraction pattern (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), UV-visible absorption spectroscopy and Fourier transform infrared spectroscopy (FT-IR). The photocatalyst process reveals that prepared nanocomposites can be degraded methylene blue under solar irradiation strongly. Results showed that methylene blue and methyl orange are degraded via 64% and 56% efficiency after 70 minutes of irradiation under visible irradiation using Co₃O₄ nanoparticles respectively. The photocatalytic performance of Co₃O₄ nanoparticles was improved via linking SN-GQDs and formation SN-GQDs/ Co₃O₄ nanocomposites. UV-Vis analysis revealed that charge transfer from Co₃O₄ to SN-GQDs and prevent charge recombination in Co₃O₄ which leads to better photocatalytic efficiency. This study introduces SN-GQDs/ Co₃O₄ nanocomposites as a novel and green photocatalyst agent.