Defect Engineering of Bi2WO6 for Enhanced Photocatalytic Degradation of Antibiotic Pollutants.

Infiltration of excessive antibiotics into aquatic ecosystems plays a significant role in antibiotic resistance, a major global health challenge. It is therefore critical to develop effective technologies for their removal. Herein, defect-rich Bi2WO6 nanoparticles are solvothermally prepared via epitaxial growth on pristine Bi2WO6 seed nanocrystals, and the efficiency of the photocatalytic degradation of ciprofloxacin, a common antibiotic, is found to increase markedly from 62.51% to 98.27% under visible photoirradiation for 60 min. This is due to the formation of a large number of structural defects, where the synergistic interactions between grain boundaries and adjacent dislocations and oxygen vacancies lead to an improved separation and migration efficiency of photogenerated carriers and facilitate the adsorption and degradation of ciprofloxacin, as confirmed in experimental and theoretical studies. Results from this work demonstrate the unique potential of defect engineering for enhanced photocatalytic performance, a critical step in removing antibiotic contaminants in aquatic ecosystems.