Facile synthesis of double-mesoporous-shelled hollow spheres of Cu-CuFe2O4/SiO2 composite as excellent Fenton catalyst

Heterogeneous Fenton-like process is very attractive in environmental treatment. However, acidic and neutral solutions are always needed in order to obtain the excellent catalytic activity, which limited the application. In this work, Cu-CuFe2O4/SiO2 hollow spheres with double-mesoporous shells were synthesized by a solvothermal method. The composite showed excellent catalytic activity for degradation of methylene blue (MB) among wide pH range (from 3.87 to 10.08) in dark. Effects of experimental conditions on the catalytic activity were studied. A catalytic mechanism was proposed based on the experimental results, which the synergetic action between Fe3+/Fe2+ and Cu2+/Cu+ redox pairs induced the excellent catalytic properties. Simultaneously, the Cu-0 helped the reduction of Fe3+ at to regenerate Fe2+ and enhanced the catalytic activity. Meanwhile, the catalyst exhibited high stability and good reusability characteristics, which showed great potential for the actual application in wastewater treatment.