文摘
A series of novel magnetically separable Fe3O4/ZnO/CoWO4 nanocomposites with different contents of CoWO4 were fabricated using a facile refluxing method at 96 °C followed by a calcination step. The structure, purity, morphology, spectroscopic, and magnetic properties of the prepared samples were characterized by XRD, EDX, SEM, TEM, UV–vis DRS, FT-IR, PL, and VSM techniques. Photocatalytic activity of the nanocomposites was investigated by degradation of rhodamine B, methylene blue, methyl orange, and fuchsine under visible-light irradiation. The results showed remarkably enhanced activity for the Fe3O4/ZnO/CoWO4 (30%) nanocomposite relative to the Fe3O4/ZnO and Fe3O4/CoWO4 samples. The degradation rate constant of RhB over the optimal nanocomposite is nearly 24 and 5 times higher than those of the Fe3O4/ZnO and Fe3O4/CoWO4 samples, respectively. The intensive absorption of visible light and separation efficiency of the photogenerated electron–hole pairs in the ternary nanocomposites were confirmed by UV–vis DRS and PL techniques, respectively. In addition, a plausible mechanism for separation of the electron–hole pairs based on p–n heterojunction was proposed.
