Enhanced visible-light photocatalytic degradation of tetracycline by a novel hollow BiOCl@CeO2 heterostructured microspheres: Structural characterization and reaction mechanism

A high-efficiency hollow [email protected]2 heterostructured microspheres with type-II staggered-gap type was successfully synthesized by precipitation-hydrothermal process loaded with BiOCl nanoparticles on CeO2 microspheres. XRD, FT-IR, EDS, SEM, HRTEM and XPS results show that the prepared materials have good crystallization, morphology and retain hollow spherical structure of CeO2. Batch experiments indicate that the photocatalytic performance of [email protected]2 towards Tetracycline (TC) is superior to pure BiOCl or CeO2 owing to the distinctive hollow structures and the formed heterostructure between BiOCl and CeO2. Cyclic experiment exhibits that the optimal [email protected]2 photocatalyst can still photodegrade more than 80% of TC in 120 min after 4 cycles. Additionally, the reactive oxidation species (ROS) trapping experiments reveal that the critical ROS include photogenerated holes (h+) and superoxide radical anions (O2−). Finally, the possible degradation pathways of TC and enhanced photodegradation mechanism was systematically discussed. On this basis, the hollow [email protected]2 heterostructured microspheres provide a new alternative with great potential in efficient visible-light-driven photodegradation of persistent organic pollutants.