Organic Dyes and Perfluorooctanoic Acid Decompositions by Cerium- and Copper-Modified Commercial TiO2 under Visible Light

The study focuses on doping low-cost commercial TiO2 (P25) to synthesize composite photocatalysts, Cu/TiO2 and Ce/TiO2, which decompose organic dyes and perfluorooctanoic acid (PFOA) under mostly visible light of a Xenon lamp. By the basic impregnation method, copper and cerium are successfully doped in P25 with different contents, which is confirmed by some structural analysis, such as X-ray analysis, inductively coupled plasma optical emission spectroscopy, and scanning electron microscopy. The optical band gaps of P25, Cu/P25/1, Cu/P25/5, Ce/P25/1, and Ce/P25/5 are respectively 3.10, 2.96, 2.93, 2.84, and 2.92 eV. Under the Xenon lamp illumination (300-700 nm, 95% visible light), the decomposition ability of Ce/P25/1 with organic dye is the best, 96.7% methylene blue decomposition after 30 minutes, and methyl orange is 90.4% after 50 minutes. The study also looks at how different types of dyes affect the ability of the photocatalysts to break down substances by examining how well the photocatalysts can adsorb the dyes. Moreover, about 22.6% of PFOA is degraded by Ce/P25/1 under the Xenon lamp illumination (300-700 nm, 95% visible light). Therefore, this research compares photocatalytic materials synthesized from cheap commercial sources to decompose pollutants in water, contributing to the development of wastewater treatment technology in Vietnam.