Hierarchically periodic macroporous bismuth vanadate with engineered oxygen vacancies for enhanced photo-oxidation performance

Abstract

Controlling morphology and engineering surface defects are two widely employed strategies for enhancing catalyst activity, impacting the photodegradation of antibiotics and the photo-oxidation of water to generate oxygen. The hierarchical periodic macroporous structure reduces the migration distance of photo-excited carriers, lowers the electron–hole recombination rate, and increases the number of active sites by providing a larger surface area, all of which contribute to improved catalytic efficiency. A key aspect of surface defect engineering is the study of oxygen vacancies, which can act as electron donors, promoting carrier separation and thereby enhancing catalytic performance. The combined effects of these two features significantly enhance the catalyst’s photo-oxidation capabilities. By contrast to traditional methods that create oxygen vacancies during the synthesis process, this study introduces additional oxygen vacancies through a secondary treatment applied after the catalyst has been produced.