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The increasing presence of pharmaceutical pollutants, such as acetaminophen, in water bodies poses a significant environmental challenge due to their persistence and potential toxicity. This study investigated the enhanced photodegradation of acetaminophen using ZnO-NiO nanofibers as superior photocatalysts. The nanofibers synthesized with varying NiO contents (designated as ZN0.5, ZN1, ZN1.5, and ZN2), were characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), Raman, FTIR, Brunauer–Emmett–Teller (BET) analysis, and diffuse reflectance spectroscopy (DRS) to elucidate their structural, morphological, and optical properties. Thermogravimetric analysis (TGA) indicated that the nanofibers exhibit high thermal stability, with major weight loss attributed to the decomposition of the polymer matrix and residual organics. The BET analysis revealed that the specific surface area remains stable after increasing the NiO content up to a certain ratio. This stability correlates with the enhanced photocatalytic performance due to increased light absorption and improved charge separation. The diffuse reflectance spectra and Kubelka–Munk plots demonstrated a reduction in bandgap energy with higher NiO content, facilitating greater visible light absorption. Photocatalytic experiments under visible light irradiation, in the presence of peroxymonosulfate (PMS), showed that the ZN1.5 nanofibers achieved the highest acetaminophen degradation rate, i.e., 92%, within 3 h. Mechanistic studies, supported by radical trapping experiments, revealed that the improved photocatalytic efficiency is due to the synergistic effects of ZnO and NiO heterojunctions, which enhance charge separation and reactive oxygen species (ROS) generation. This research highlights the potential of ZnO-NiO nanofibers as effective photocatalysts for the degradation of pharmaceutical pollutants. The findings demonstrate that optimizing the composition and structure of nanofibers can significantly improve their environmental remediation capabilities, providing a promising solution for sustainable water treatment. [ABSTRACT FROM AUTHOR]

The current work focuses on the photo degradation of organic pollutants, particularly methylene blue (MB) dye, and the production of hydrogen as green energy using a composite of silver phosphate Ag3PO4 (AP) and barium oxide/silver phosphate BaO@Ag3PO4 (APB) as a photocatalyst. This composite was successfully synthesized using a chemical co-precipitation approach. The physicochemical properties of the obtained samples were investigated using scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR), ultraviolet–visible diffuse reflectance spectroscopy (UV–Vis/DRS), and photoluminescence (PL) spectrophotometry. From XRD, the average crystallite sizes of AP and APB are 39.1 and 46 nm, respectively, with a homogeneous morphology detected by SEM. UV and PL experiments showed that the compound is active under visible light, with an improvement in the lifetimes of the electrons and the holes in the presence of BaO with Ag3PO4. The as-synthesized APB photocatalyst sample showed a remarkably high degradation efficiency of MB (20 ppm, 50 mL) of around 94%, with a hydrogen production yield of around 7538 μmol/(h·g), after 120 min of illumination, which is greater than the degradation efficiency of the AP photocatalyst sample, which was about 88%. The high photodegradation efficiency was attributed to the electronic promotion effect of the BaO particles. The APB composite demonstrated an increased photocatalytic performance in effectively degrading an organic dye (MB) with no secondary pollutants when exposed to visible light irradiation. [ABSTRACT FROM AUTHOR]

Binary composite WS2/TiO2 nanofibers (WTN) were elaborated by electrospinning technique. The photocatalytic efficiency of the binary nanofibers was changed via different ratios between WS2 and TiO2. The structural, morphological and optical properties of the prepared nanofibers were evaluated by Raman spectroscopy, Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM) and UV-Vis diffuse reflectance spectroscopy (UV-vis/DRS), respectively. The prepared nanofibers showed a remarkable performance in photocatalytic efficiency of phenol compound degradation under visible light. WTN nanofibers showed superior photocatalytic activity (83%) and high stability of several cycles under visible light. Therefore, WS2/TiO2 nanofibers have great prospects for the treatment of wastewater from toxic organic contamination due to their excellent photocatalytic performance reusability and recyclability. [ABSTRACT FROM AUTHOR]

Magnetite zinc oxide (MZ) (Fe3O4/ZnO) with different ratios of reduced graphene oxide (rGO) was synthesized using the solid-state method. The structural and optical properties of the nanocomposites were analyzed using transmission electron microscopy (TEM), X-ray diffraction (XRD), Raman spectroscopy, Fourier-transform infrared spectroscopy (FTIR), ultraviolet–visible diffuse reflectance spectroscopy (UV–Vis/DRS), and photoluminescence (PL) spectrophotometry. In particular, the analyses show higher photocatalytic movement for crystalline nanocomposite (MZG) than MZ and ZnO nanoparticles. The photocatalytic degradation of methylene blue (MB) with crystalline ZnO for 1.5 h under visible light was 12%. By contrast, the photocatalytic activity for MZG was more than 98.5%. The superior photocatalytic activity of the crystalline nanocomposite was detected to be due to the synergistic effect between magnetite and zinc oxide in the presence of reduced graphene oxide. Moreover, the fabricated nanocomposite had high electron–hole stability. The crystalline nanocomposite was stable when the material was used several times. [ABSTRACT FROM AUTHOR]