Photocatalytic Degradation of Methyl Orange by Ni2+-Doped Anatase TiO2/CoFe2O4 Composites Under Solar Light Irradiation

Ni2+-doped anatase TiO2/CoFe2O4 (Ni2+-TiO2/CoFe2O4) composites with core-shell structure were prepared by an ultrasonic method. The core CoFe2O4 nanoparticles were synthesized via co-precipitation method and the photoactive shell Ni2+-doped TiO2 nanoparticles were directly coated on the CoFe2O4 by the ultrasonic-induced hydrolysis reaction of tetrabutyl titanate in a nickel(II) sulfate aqueous solution, then the composites were calcined at different temperature. The resultant Ni2+-TiO2/CoFe2O4 composites exhibited good magnetic response. The photocatalytic activities of Ni2+-TiO2/CoFe2O4 composites were evaluated by the photocatalytic degradation of methyl orange under solar light irradiation. The results showed that Ni-doping concentration and calcined temperature had effect on the photocatalytic activities of Ni2+-TiO2/CoFe2O4 composites. Ni2+ doping effectively improved photocatalytic activities of TiO2/CoFe2O4 composites and the photocatalytic activities of Ni2+-TiO2/CoFe2O4 with an optimal doping concentration of 1.5 % were four times that of undoped TiO2/CoFe2O4. Moreover, H2O2 assisted Ni2+-TiO2/CoFe2O4 composites under solar light irradiation was an effective and promising process for decolourization of dye-containing wastewater.