Akademik Veri Yönetim Sistemi
JOURNAL OF MOLECULAR STRUCTURE, cilt.1364, 2026 (SCI-Expanded, Scopus)
This study investigates the photocatalytic degradation of Remazol Black 5 (RB5), a vinyl sulfone-type azo dye known for its environmental persistence and severe health hazards, using various metal oxide (MeO) catalysts under different light sources and experimental conditions. Semiconductor photocatalysts, including TiO2, ZnO, Bi2O3, and CTAB-assisted TiO2, were synthesized via different preparation methods and characterized using Brunauer-Emmett-Teller (BET), X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, diffuse reflectance spectroscopy (DRS), scanning electron microscopy (SEM), photoluminescence spectroscopy (PL) techniques. Photocatalytic experiments were conducted under UV light, natural sunlight, and visible lamp irradiation, with dye concentration monitored by UV-Vis spectrophotometry. Among the tested catalysts, TiO2 exhibited superior photocatalytic activity, achieving complete degradation of RB5 within 30 min under solar irradiation and 45 min under UV-B light. CTAB-assisted TiO2 also enhanced degradation within 15 min under natural sunlight. The highest pseudo-first-order rate constant was obtained with TiO2 under solar light (0.20 min-1), surpassing other metal oxide systems. Furthermore, the CTAB-modified TiO2 (TiO2-CTAB) demonstrated even higher apparent rate constants (0.39 min-1 under sunlight and 0.21 min-1 under UV light), attributed to improved charge separation and surface reactivity. Both catalysts exhibited measurable adsorption behavior; however, TiO2 primarily acted through photocatalytic pathways, while TiO2-CTAB operated via a synergistic adsorption-photocatalytic mechanism, enhancing overall dye removal efficiency. The results emphasize the critical influence of catalyst structure, synthesis method, and irradiation conditions on degradation efficiency. This work demonstrates the potential of TiO2-based photocatalysis as a sustainable and efficient technology for the removal of hazardous dyes from wastewater, particularly in systems utilizing solar energy.