High photocatalytic activity of magnetically separable ZnO and Ag/ZnO supported on Mg-ferrite nanoparticles

Abstract Facile precipitation–deposition method has been used to prepare magnetically recoverable MgFe2O4/ZnO and MgFe2O4/ZnO/Ag nanocomposites. The valuation of photocatalytic activity of prepared powders was carried out using Congo red (CR) as a model of chemical pollutants, under visible light irradiation. The XRD, FE-SEM, TEM, DRS and VSM were applied to characterize the prepared nanocomposites. Structural, compositional and morphological analysis showed the successful formation of the nanocomposites with spherical shapes. The particle sizes of all the compositions were in the range of ∼39–69 nm. The MgFe2O4/ZnO and MgFe2O4/ZnO/Ag nano-photocatalyst showed higher degradation efficiency than the pure ZnO and Mg-ferrite. The enhanced photocatalytic activity of the nanocomposites is attributed to the development of a suitable internal structure between ZnO and MgFe2O4. The measured saturation magnetization of the nanocomposites with and without doping of Ag were 8.09 and 7.71 emu/g, respectively, indicating that these photocatalysts could be quickly separated from the reaction solution by an external magnetic field.