A magnetic ZnFe2O4/ZnO/perlite nanocomposite for photocatalytic degradation of organic pollutants under LED visible light irradiation

New magnetically ZnFe₂O₄/ZnO/perlite nanocomposites with different molar ratios were successfully synthesized. The as-prepared samples were characterized physically and chemically using Fourier-transform infrared spectroscopy (FT-IR), powder X-ray diffraction (XRD), scanning electron microscopy imaging (SEM), energy-dispersive X-ray spectroscopy (EDX), vibrating sample magnetometer (VSM) and diffuse reflectance spectroscopy (DRS). ZnFe₂O₄/ZnO/perlite nanocomposites were explored for their photocatalytic performance by the decomposition of methylene blue (MB) and 4-nitrophenol (4-NP) under visible LED light radiation. This experiment indicated that nanocomposite with a molar ratio of 2:1 ZnFe₂O₄:ZnO on perlite showed the highest photocatalytic activity and degraded 97 and 67% of MB (20 mgL^-1) and 4-NP (10 mgL^-1) aqueous solutions within 150 min, respectively. The enhanced photocatalytic activity of this composite ascribed to the efficient separation of photoinduced electrons and holes. In addition, it can be separated easily by an external magnet and reused twice more.