Preparation and Photocatalytic Properties of Hollow Spheres-like Zn-doped CuO/CuAl_2O_4 Composite Photocatalysts

Zn-doped CuO/CuAl2O4 composite hollow spheres with high specific surface area were synthesized by hydrothermal method, using glucose as template and Zn(NO3)2·6H2O, Cu(NO3)2·3H2O, Al(NO3)3·9H2O as raw materials. The samples were characterized by XRD, SEM, HRTEM, BET, DRS and PL spectra. The results showed that Zndoped CuO/CuAl2O4 composites possessed hollow microspheres shape with specific surface area up to 214.97 m2/g and diameter of about 2 μm after calcined at 600℃. The Zn doped photocatalysts exhibited enhanced absorption intensity, decreased electron-hole recombination. Further photocatalytic activities of the samples were greatly increased. The influences of calcination temperature and Zn doping content on photocatalytic activities of the samples were investigated by measuring the degradation rate of methyl orange(MO) under simulated sunlight irradiation. The sample doped with 0.5wt% Zn which was calcined at 600℃ showed the highest efficiency. Under visible light irradiation for 60 min, the decolorizing efficiency of 25 mg/L MO by 0.5 g/L photocatalyst reached 97%.