Engineered g-C3N4/MnO2 Nanocomposite for Exceptional Photocatalytic Methylene Blue Degradation and Robust Antibacterial Impact

Abstract

In this work, we reported the simple one-step wet impregnation method of g-C₃N₄/MnO₂ nanocomposites aimed at improving the photocatalytic degradation efficiency of methylene blue dye. The synthesized catalysts underwent comprehensive characterization using various techniques such as X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and ultraviolet-visible diffuse reflectance spectroscopy (UV-vis DRS) to investigate their physicochemical properties. Their photocatalytic performance was evaluated by the degradation of methylene blue (MB) dye under visible light irradiation. Consequently, the MnO₂/g-C₃N₄ nanocomposite demonstrates superior photocatalytic degradation performance compared to both bare MnO₂ and g-C₃N₄. This enhancement is attributed to the improved efficiency of charge carrier separation and interfacial charge transfer within the nanocomposite structure. The degradation efficiency of MnO₂/g-C₃N₄ nanocomposite was found 89% of MB under visible light irradiation at 120 min. Meanwhile, the recyclability analysis demonstrated that the MnO₂/g-C₃N₄ nanocomposite can be recycled four times. Furthermore, the substance demonstrated positive antibacterial activity against Escherichia coli, and Staphylococcus aureus bacterial strains. These findings suggest that the MnO₂/g-C₃N₄ nanocomposite, with its dual roles as a photocatalyst and an antibacterial agent, has potential applications in environmental decontamination.