Interface oxygen vacancy-enhanced core-shell composite material CeO2@SrTiO3 utilizes Z-scheme heterojunction to achieve efficient degradation of tetracycline antibiotics

The misuse of tetracycline (TC) harms ecosystems and human health. CeO 2 , with its stable structure and abundant oxygen vacancies (OVs), is a focus for TC photocatalytic degradation but suffers from high carrier recombination, poor visible light absorption, and nanoparticle agglomeration. In this study, to overcome the drawbacks of CeO 2 mentioned above, PVP-modified SrTiO 3 (STO) was used as the support, PVP efficiently captures the precursor Ce 3 + by taking advantage of its network structure. And a layer of ultrafine nanoparticles CeO 2 was uniformly loaded on its surface by hydrothermal synthesis to form a core-shell structure composite material CeO 2 @STO, effectively solving the problem of CeO 2 nanoparticle agglomeration. A large specific surface area and sufficient active sites have been obtained, which enables CeO 2 to fully exert its catalytic degradation ability. The TC removal rate of the composite material CeO 2 @STO-2 was 80.50 %, which was 1.5 times and 2.5 times that of CeO 2 and STO respectively, and still maintained a high TC removal rate after 5 cycles, with only a decrease of 10.03 %. Furthermore, for tetracycline antibiotics such as chloramphenicol (CTC) and oxytetracycline (OTC), the removal rates were as high as 85.60 % and 78.60 %, which were significantly higher than those of CeO 2 and STO. The enhanced catalytic performance is attributed to the broadened visible-light absorption of composites, a Z-scheme heterostructure that suppresses carrier recombination, and interfacial doping that enriches oxygen vacancies. Toxicity simulations and bean sprout experiments confirmed significantly reduced toxicity after degradation. This work provides a novel strategy for developing high-performance OV-rich core-shell photocatalysts.