UV-Irradiated Photocatalytic Activity of α-Fe2O3/ZnO Nanocomposites for Wastewater Treatment

This work demonstrates the successful synthesis of pure α -Fe 2 O 3 , pure ZnO, and α -Fe 2 O 3 /ZnO nanocomposites with weight ratios of 1:1, 1:2, 1:3, and 1:4 by an efficient hydrothermal method for wastewater treatment. The structural, morphological, optical, and magnetic properties of the synthesized samples were characterized by x-ray diffraction (XRD), high-resolution transmission electron microscopy (HR-TEM), ultraviolet–visible (UV–Vis) spectroscopy, and vibrating-sample magnetometry (VSM), respectively. The XRD pattern confirmed the successful formation of the synthesized samples. Particle size in the range of 30–36 nm was calculated for the nanocomposite using HR-TEM. UV–Vis spectroscopy was used to calculate the optical bandgap of the synthesized nanocomposites, which varied from 1.96 eV (FZ11) to 2.27 eV (FZ14). This difference was explained by the introduction of ZnO, which is a wide-bandgap semiconductor. The value of magnetization decreased from 0.37 emu/g to 0.04 emu/g as the content of ZnO increased. The α -Fe 2 O 3 /ZnO nanocomposite with a weight ratio of 1:4 showed 85% photocatalytic degradation of methylene blue (MB) dye under UV light illumination with synchronized extraction for 105 min.