A novel carbon doped CeO2/g-C3N4 heterostructure for disinfection of microorganisms and degradation of Malachite green and Amoxicillin under sunlight

The fabrication of semiconductor heterojunction with defect engineering is an efficient technique to boost photocatalytic activity. In this study, a novel step-scheme heterojunction C-CeO2/g-C3N4 nanocomposite was developed via the hydrothermal method for the degradation of aqueous dye and antibiotics in sunlight. The photocatalytic experiment of the CeO2/g-C3N4 heterojunction nanocomposite reveals superior photocatalytic activity and significant reusability. Further, 91.9 % of Malachite green (MG) and 87.5% of Amoxicillin(AMX) were degraded by C-CeO2/g-C3N4 nanocomposite under 150 mins of sunlight irradiation, which is ∼ 1.78 folds of the photodegradation performance of C-CeO2. The decomposition of MG and AMX into non-toxic secondary compounds was verified by total organic carbon and high-performance liquid chromatography analysis. Further, the migration and separation of charge carriers due to photons were confirmed through electrochemical analysis and, photoluminescence spectroscopy. The potential S-Scheme charge transfer pathway for improved photocatalytic activity was postulated via the quenching experiment, Mott Schottky (M-S) plot, and XPS Valance band spectroscopy (VB-XPS). In addition, the C-CeO2/g-C3N4 nanocomposite displays excellent bactericidal and fungicidal activity against pathogenic microorganisms S. aureus, E. coli, and C. albican. Hence, the synthesized S-Scheme heterojunction C-CeO2/g-C3N4 nanocomposite is an ideal catalyst for the detoxification of industrial wastewater.