A new photocatalyst InGaZn0.3Cu0.7O4 with co-catalyst CuO to decompose tetracycline efficiently.

• A new photocatalyst InGaZn 0.3 Cu 0.7 O 4 with CuO to decompose tetracycline efficiently. • The Cu2+ doping in InGaZnO 4 significantly improves the light absorption properties. • The layered structure of InGaZn 0.3 Cu 0.7 O 4 is conducive to the enhancement of photodegradation performance. Herein, we reported a new photocatalyst InGaZn 0.3 Cu 0.7 O 4 with co-catalyst CuO for the photo-oxidation of tetracycline. Copper doping in InGaZnO 4 significantly reduced the bandgap and enhances the absorption of visible light. The photocatalytic performance was further enhanced by making a composite with CuO. In the photo-oxidation reaction of tetracycline, the kinetic constant of the optimal composite is 0.0111 min−1, which is 3.0 and 10.1 times higher than those of InGaZnO 4 and InGaCuO 4 , respectively. The photocatalytic mechanism suggested that photogenerated holes play the most important role in the oxidation of tetracycline. [ABSTRACT FROM AUTHOR]