CuS@Cu-CD composites as efficient heterogeneous Fenton-like catalysts for the photodegradation of tetracycline

In this work, CuS@Cu-CD composites were synthesized and employed as Fenton-like catalysts. CuS significantly enhanced the photodegradation activity of tetracycline (TC) when decorated with Cu-doped-carbon dots (Cu-CDs). The influence of initial pH, dosage of catalyst, and H2O2 concentration on the catalyst performance was investigated. Radical trapping experiments proved that ·O2− and h+ played critical roles and ·OH played a moderate role in the degradation of TC. Mechanism analyses demonstrated that Cu2+/Cu+ redox circulation could be accelerated by the introduction of Cu into carbon dots, which further facilitated H2O2 consumption and resulted in higher TC degradation efficiency.