Preparation of La-Nd co-doped ZnO nanospheres and application on effluent treatment containing reactive dyes

Zinc oxide (ZnO) nanospheres and La-Nd co-doped spherical ZnO composite were prepared by solvothermal method with zinc chloride and urea, ethylene glycol (EG) as morphology controller, to obtain excellent photocatalytic effect and degradation of pollutants containing reactive dyes. The morphology, structure and chemical composition were described by scanning electron microscopy (SEM), X-ray diffractometry (XRD), X-ray photoelectron spectroscopy (XPS) and diffuse reflection spectrum (DRS). The results showed that the size of La-Nd co-doped spherical ZnO about 130 nm, and the XRD results showed sharper characteristic peak. Meanwhile, the band gap of 2%La-1%Nd co-doped ZnO reduced from 3.23 eV to 2.97 eV. The degradation of effluent treatment containing reactive dyes like reactive red 24 (RR24) or reactive yellow 145 (RY145) was reached 99.99% under UV illumination for 75 min with 2%La-1%Nd co-doped ZnO as catalyst, which showed remarkable photocatalytic performance. After 120 min, removal efficiencies of chemical oxygen demand (COD) and total organic carbon (TOC) for RR24 discharge liquid attained 76.68% and 73.16% respectively, meanwhile, COD and TOC removal efficiencies for RY145 discharge liquid reached 76.32% and 72.36%.