Magnetically separable Au-TiO2/nanocube ZnFe2O4 composite for chlortetracycline removal in wastewater under visible light

Magnetically separable Au-TiO2/nanocube ZnFe2O4 composite exhibit an outstanding photocatalytic activity in degradation of chlortetracycline (CTC) under visible light irradiation. [Display omitted] •A new type ternary Au-TiO2/nanocube ZnFe2O4.•The Au-TiO2/nanocube ZnFe2O4 shows superior photocatalytic activity.•The chlortetracycline can be removed by Au-TiO2/nanocube ZnFe2O4.•Cycle degradation tests show the catalyst was highly active, stable and recoverable. Magnetically recyclable Au-TiO2/nanocube ZnFe2O4 (Au-TiO2/NC ZFO) composite photocatalysts have been successfully prepared by a hydrothermal method. It was revealed that Au-TiO2/NC ZFO composite with 25% mass percentage of Au-TiO2 exhibited a significantly enhanced photocatalytic efficiency toward chlortetracycline (CTC) degradation as compared to the binary TiO2/NC ZFO composite. The enhanced performance can be attributed to the addition of Au nanoparticles, which act as electron traps aiding the electron-hole separation and increasing the light absorption through the surface plasmon resonance effect. The synthesized catalyst showed good stability after three cycles and could be easily separated by a magnet and reused.