Cage-like magnetic CdS/MgFe2O4 S-scheme heterojunction material for photocatalytic decomposition of tetracycline hydrochloride

The cage-like CdS/MgFe2O4 Step-scheme heterojunctions (S-scheme heterojunction) material was synthesized by loading CdS onto the surface of magnetic MgFe2O4. The crystal structure, morphology and properties of the catalyst were fully characterized, and the photocatalytic performance of the catalyst was investigated by photodegradation of tetracycline hydrochloride (TCH). The crystalline structure of CdS/MgFe2O4 is dominated by the cubic spinel structure of MgFe2O4 with a hollow cage morphology. CdS and MgFe2O4 form a tight-binding S-scheme heterostructure, which can accelerate the recombination of ineffective charge carriers and promote the separation of the effective charge carriers via the internal electric field, enabling CdS/MgFe2O4 to maintain an optimal redox potential. Compared with pure CdS and MgFe2O4, CdS/MgFe2O4 is more effective on degradation of TCH. Moreover, magnetic separation, recovery, and recycling of the composite catalyst can be achieved without secondary contamination by using the magnetic properties of the CdS/MgFe2O4.