Constructing oxygen defect-rich Bi2WO6/CeO2 S-scheme heterojunction for boosted photocatalytic antibiotic removal

Efficient photocatalytic eradication of antibiotic contaminant from water is of significance for the sustainability of the aquatic environment. Oxygen defective Bi2WO6/CeO2 S-scheme heterojunctions were obtained by two-step hydrothermal processes. The optimal Bi2WO6/CeO2 heterostructure (BC-10) delivered degradation efficiencies of 86.6 % and 87.1 % for tetracycline (TC) and ciprofloxacin (CIP), respectively. The boosted photocatalytic performance of BC-10 was attributed to the increased specific surface area, S-scheme construction and the formed oxygen-defect energy level which promoted the fast charge transfer and separation of photoinduced h+/e– pairs. In addition, experiments confirmed that BC-10 possessed a good catalytic performance for other organic pollutants. The toxic behavior of the TC-removal solution was verified via the Ecological Structure-Activity Relationship (ECOSAR) model and hemp-pea growth experiment, and the possible photocatalytic degradation mechanism of TC and CIP on BC-10 was proposed. This work offers an applicable construction concept of advanced photocatalysts with high redox capacity for wastewater remediation.