Preparation, magnetic properties, and photocatalytic performance under natural daylight irradiation of Fe3O4-ZnO core/shell nanoparticles designed on reduced GO platelet

Ternary mesoporous nanocomposites of RGO/Fe3O4-ZnO were prepared successfully via hydrothermal technique. Fe3O4-ZnO core/shell nanoparticles were decorated on the surface of reduced graphene oxide platelet to improve charge separation efficiency and magnetic properties. The phase, microstructure and specific surface area of the prepared samples were determined via X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy/selected area electron diffraction (TEM/SAED) and Brunauer-Emmett-Teller (BET) techniques. A vibrating sample magnetometer (VSM) was used for recording the magnetization hysteresis curves. The methylene blue (MB) degradation and photocatalytic activities of prepared catalysts were examined under natural daylight irradiation. The magnetic properties of the RFZ photocatalyst increased compared with the FZ from 12.45 emu g−1 to 20.18 emu g−1. The specific surface area (as,BET) for the RFZ compared to the FZ increased from 31.56 m2 g−1 to 36.05 m2 g−1. The RFZ photocatalyst, as a result of synergistic effects, indicated an excellent performance for treatment of MB dye. The photocatalytic reactions obeyed pseudo-first-order kinetics and apparent rate constant (kap) of RFZ photocatalyst increased compared to FZ. Furthermore, the RFZ photocatalyst could be recycling using a common magnet besides to the high efficiency of degradation. The repeatability of the photocatalytic activity after 10 cycles was additionally tested and revealed that the RFZ photocatalyst up to 8 cycles showed a small drop in catalysis efficiency. Thus, it was concluded that the RFZ ternary photocatalyst can be an economical multifunctional photocatalyst for the degradation of unsafe compounds in wastewater.