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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]

Mn3O4 were synthesized via the hydrothermal method at 200°C for 24 h, using surfactants. The resultant products were examined by powder X-ray diffraction (XRD), Raman spectroscopy, Fourier transform infrared spectroscopy (FTIR), transmission electronic microscope (TEM), UV-visible spectroscopy and BET surface area analysis. The as-prepared materials were used for the adsorption of methylene blue dye (MB). The effect of various experimental parameters (initial concentration, adsorbent dose and temperature) and optimal experimental conditions were ascertained by response surface methodology using Doehlert model. Finally, the antibacterial activity of Mn3O4 nanoparticles was tested. [ABSTRACT FROM AUTHOR]

Undoped and Mg-doped (y = [Mg2+]/[Fe3+] = 1, 2, 3, and 4 at.%) Fe2O3 thin films were synthesized by a simple spray pyrolysis technique. The thin films were extensively characterized. X-ray diffraction (XRD) and energy-dispersive spectroscopy (EDS) analysis confirmed the successful insertion of Mg in the rhombohedral structure of Fe2O3. In addition, scanning electronic microscope (SEM) and confocal microscope (CM) images showed a homogenous texture of the film, which was free of defects. The rough surface of the film obtained by spray pyrolysis is an important feature for photocatalysis and gas sensor applications. The direct band gap of the doped Fe2O3 films obtained for [Mg2+]/[Fe3+] = 3 at.% was Edir = 2.20 eV, which recommends the Mg-doped iron oxide as an optical window or buffer layer in solar cell devices. The photodegradation performance of Mg-doped Fe2O3 was assessed by studying the removal of methylene blue (MB) under sunlight irradiation, with an effective removal efficiency of 90% within 180 min. The excellent photodegradation activity was attributed to the strong absorption of Mg-doped Fe2O3 in the UV and most of the visible light, and to the effective separation of photogenerated charge carriers. [ABSTRACT FROM AUTHOR]

The α-Fe2O3/TiO2 nanostructure material, synthesized on FTO (fluorine-doped tin oxide) substrate using the hydrothermal method at 180 °C for 5 h, exhibits an enhanced performance in the photocatalytic degradation of an organic dye. The optical band gap was found to decrease compared to the TiO2 one. The photocatalytic performances of the as-prepared heterojunction were evaluated with the degradation of methylene blue (MB) in an aqueous medium. The results revealed that the photocatalytic activity of the Fe2O3/TiO2/FTO was much higher than that of the pure TiO2. In addition, the photocurrent of the Fe2O3/TiO2/FTO heterojunction was remarkably higher than that of the bare TiO2 electrode. The obtained results indicate that the heterojunction formed between Fe2O3 and TiO2significantly improved the separation efficiency of the photo-generated electron–hole pairs. The electrochemical properties of the as-synthesized nanocomposite materials (α-Fe2O3/TiO2) were also evaluated with cyclic voltammetry for 1000 cycles. This nanocomposite exhibited an enhanced specific discharge capacity compared to the Fe2O3 nanomaterial. The as-produced material proved to have an impressive performance as a high-capacity anode for Na+-ion batteries. [ABSTRACT FROM AUTHOR]

BiCePO ( x = 0.00-0.08) nanorods were synthesized using the solvothermal method at 160 °C. The successful incorporation of Bi dopant ions into the hexagonal structure of CePO was verified by XRD, EDX, FTIR, and UV-Vis spectroscopic techniques. The XRD and IR spectroscopy results have demonstrated that low bismuth doping does not alter the CePO structure and good nanocrystalline materials are synthesized. The temperature dependence of conductivity, for both the pure and Bi-doped samples, obeys the Arrhenius law of conduction. The Bi doping process has been successful in effectively tuning the optical band gap energy and electronic band structure of the cerium phosphate materials. Electrochemical tests showed an improved capacity when increasing the Bi content and a stable cycling performance of the BiCePO ( x = 0.00, 0.02, and 0.08) nanorods, making them interesting for potential further investigations. [ABSTRACT FROM AUTHOR]

Cobalt-nickel-manganese pyrophosphate nanostructures with formula CoNiMnPO were prepared via the hydrothermal method at 150 °C, with further calcinations at 500 °C. A structural analysis of CoNiMnPO samples was carried out using X-ray diffraction (XRD). The effect of Co substitution on the structural, electrical, and electrochemical properties of CoNiMnPO is reported. The electrochemical results show that the specific capacity increases from 59 to 205 mAh/g with increasing Co content. This study demonstrates the Co substitution effect on the mixed electrical conductivity. The temperature dependence of the dc electrical conductivity, for both pure and Co-doped samples, obeys the Arrhenius law. The frequency dependence of ac conductivity for the materials exhibited a Jonscher's universal power law. The plots of pre-exponent (n) versus temperature suggested that the conduction mechanism can be described using correlated barrier hopping model. The improved electrical conductivity and electrochemical proprieties of CoNiMnPO nanomaterials could be ascribed to the synergistic effect of nickel and cobalt ions. The best results have been obtained for the composition x(Co) = 0.75, where the electrical conductivity is maximum, and the CoNiMnPO demonstrates the highest specific capacity, implying their promising potential applications in the energy storage. [ABSTRACT FROM AUTHOR]

Abstract: The x(CuO)/(1−x)Ni(OH)2 [x=0, 0.1 and 0.3] nanocomposites were prepared by the hydrothermal method in the presence of the surfactant polyethylenglycol-10000 (PEG-10000). X-ray diffraction (XRD), infrared (IR) spectroscopy, scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were used to characterize the as-prepared samples. The increase of the CuO content led to the increase of the crystallite size of both, the β-Ni(OH)2 and the CuO. The increase in the crystallite size greatly affects the band gap energy of the as-prepared nanocomposites. The band gap energies of the x(CuO)/(1−x)Ni(OH)2 nanocomposites were estimated by UV–vis spectroscopic method. UV–vis spectroscopic results showed an apparent decrease in the direct band gap energies. The x(CuO)/(1−x)Ni(OH)2 [x=0, 0.1 and 0.3] nanocomposites show low band gap energies compared to the Ni(OH)2 bulk materials. The enhanced optical properties lead to their possible use in photocatalytic and photovoltaic applications. [Copyright &y& Elsevier]

Highlights: [•] Nanostructured pyrophosphate Ni0.25Co0.75MnP2O7 were synthesized and characterized by XRD and SEM. [•] The ac-conductivity at different values of temperature for Ni0.25Co0.75MnP2O7 nanomaterials shows frequency independence in the lower frequency range. [•] Obvious improvements of the electrical conductivity and the electrochemical properties are achieved comparatively Mn2P2O7. [•] The electrochemical behaviors of Ni0.25Co0.75MnP2O7 were studied using cyclic voltammetry. [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]