Synthesis, magnetic properties and photocatalytic activity of CuFe2O4/MgFe2O4 and MgFe2O4/CuFe2O4 core/shell nanoparticles

Tailored CuFe2O4/MgFe2O4 and MgFe2O4/CuFe2O4 core/shell nanoparticles were prepared by a precipitation method and their structures investigated by X-ray diffraction and electron microscopy. Vibrating sample magnetometry tests showed that coating CuFe2O4 with MgFe2O4 increased coercivity from 28.87 to 40.46 Oe and decreased remanant and saturation magnetisation from 9.679 to 5.523 and 45-05 to 30.0 emu g(-1) respectively, relative to uncoated particles; coating MgFe2O4 with CuFe2O4 increased remnant and saturation magnetisation from 3.026 to 7.055 and 16-36 to 24-66 emu g(-1) respectively and coercivity increased from 88.4 to 149.4 Oe. In tests to assess photocatalytic activity, the CuFe2O4/MgFe2O4 core/shell nanoparticles produced complete degradation of Congo red dye under visible light irradiation after 30 h. In the absence of visible light, the catalytic activity of MgFe204/CuFe2O4 is greater than that of CuFe2O4/MgFe2O4 core/shell nanoparticles.