Sustainable Water Remediation Through Degradation of Organic Pollutants Using Green-Synthesized Cerium and Sulfur-Doped TiO2 Nanoparticles.

Eco-friendly photocatalysis offers a sustainable approach for degrading hazardous water pollutants. In this study, sulfur-doped (S─TiO2) and cerium-doped (Ce─TiO2) nanoparticles were synthesized via a green route using Syzygium cumini L. leaf extract. Comprehensive characterization via SEM, FTIR, UV-vis diffuse reflectance spectroscopy, photoluminescence (PL), Raman, and XPS confirmed successful dopant incorporation, introduced mid-gap defect states, narrowed the band gap (2.0-2.5 eV), and promoted efficient charge separation. Photocatalytic performance was optimized across varying parameters including catalyst loading, solution pH, and contact time. Under optimized conditions, S─TiO2 nanoparticles achieved degradation efficiencies of 98.5% for Rhodamine B (RhB) within 90 min, 96.0% for omeprazole (OMZ) within 30 min, and 98.1% for chlorpyrifos (PCPS) within 40 min, slightly outperforming Ce─TiO2 (97.3%, 95.55%, and 97.3%, respectively). Radical scavenger studies confirmed •OH and •O2- as the primary reactive species driving degradation. Reusability evaluations demonstrated exceptional structural and chemical stability over successive cycles with minimal activity loss. Benchmarked against literature standards, these green-synthesized nanostructures present robust potential for practical wastewater remediation applications.