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The effects of various additives (Y2O3, Ga2O3, and WO3) on photocatalytic degradation efficiency under UV light-emitting diodes (LEDs) and the optical properties of TiO2 Degussa P25 were investigated using ketoprofen and diclofenac, two non-steroidal anti-inflammatory drugs commonly detected in German rivers. Experimental results demonstrated that thin films containing these additives exhibited similar photocatalytic degradation efficiencies as pure TiO2, achieving a 30% degradation of ketoprofen over 150 min. In contrast, the Y2O3/TiO2 thin film showed significantly improved performance, achieving a 46% degradation of ketoprofen in 180 min. Notably, the Y2O3/TiO2 system was three times more effective in degrading diclofenac compared to pure TiO2. Additionally, the Y2O3/TiO2 photocatalyst retained its activity over three successive cycles with only a slight decrease in efficiency. The photocatalytic degradation of both organic pollutants followed first-order kinetics with all photocatalysts. The investigation included SEM imaging to assess the surface homogeneity of the thin films and UV-vis solid-state spectroscopy to evaluate the impact of the additives on the energy band gap of TiO2. [ABSTRACT FROM AUTHOR]

In the current study, a novel electrochemical sensor has been developed for levofloxacin detection, by coating an Indium tin oxide (ITO) modified electrode with a thin film of Cu-nanoplatelets, WO3 quantum dots coupled to the g-C3N4 nanosheets. The prepared electrode was characterized using various analytical tools, including powder X-ray diffraction (XRD), scanning electron microscope (SEM), high resolution transmission electron microscope (HRTEM) and Fourier-Transform Infrared spectroscopy (FT-IR). The electrochemical properties of levofloxacin (LEVO) were determined by performing cyclic voltammetry (CV) and amperometric tests. The hybrid electrode exhibits a well-defined peak around 1.2 V during the anodic potential scan, which was attributed to the (LEVO) oxidation process. The measured ultrahigh sensitivity is 0.786 µA µM−1 cm−2 for a linear range of 0–70 µM in the low concentration zone and 0.312 µA µM−1 cm−2 for a linear range of 120–870 µM in the high concentration zone. A good linear correlation between the peak current and LEVO concentration in the range of 0 to 70 µM was obtained through detection and quantification limits of 0.1 µM and 0.3 µM, respectively.The WO3/g-C3N4/Cu nanoparticles that modified the ITO electrode reveals high stability, reproducibility, and repeatability, as well as selectivity for LEVO in real water samples. Analyses were also conducted on the LEVO detection in the presence of interfering substances.As far as this paper is concerned, this is the first time that a ternary nanocomposite WO3/g-C3N4/Cu has been used to detect LEVO at low and high concentrations. Application of ITO/WO3/g-C3N4/Cu as an electrochemical sensor for LEVO [ABSTRACT FROM AUTHOR]

AbstractA TiO2 photocatalyst modified with g-C3N4 and different wt% of CuO, is performed via hydrothermal method. The structural, morphological and spectroscopic characterizations are carried out. The ternary composite, g-C3N4/CuO/TiO2, exhibits greater photocatalytic activity than CuO/TiO2. The highest degradation of Levofloxacin reaches 99% and 44%, after 10 and 60 min UV irradiation over ternary and binary composites for 20 wt% of CuO, respectively, with a concentration of 5.10−3 g/L of LEVO and a photocatalyst mass of 2.10−2 g. The stability of g-C3N4/CuO/TiO2 is confirmed allowing its reuse for five successive cycles with a longer treatment time. Under solar irradiation, the degradation yield of Levo using g-C3N4/CuO/TiO2 is 100% after only 20 min. The as-synthesized nanocomposite present interesting electrochemical properties. In the medium-frequency region, the diameter of the semicircle for the g-C3N4/CuO/TiO2 electrode is much smaller than that of the CuO/TiO2 electrode, indicating a lower charge-transfer resistance. [ABSTRACT FROM AUTHOR]