A BaTiO3/WS2 composite for piezo-photocatalytic persulfate activation and ofloxacin degradation

Abstract

Piezoelectric fields can decrease the recombination rate of photogenerated electrons and holes in semiconductors and therewith increase their photocatalytic activities. Here, a BaTiO3/WS(2 )composite is synthesized and characterized, which combines piezoelectric BaTiO3 nanofibers and WS2 nanosheets. The piezo-photocatalytic effect of the composite on the persulfate activation is studied by monitoring Ofloxacin (OFL) degradation efficiency. Under mechanical forces, LED lamp irradiation, and the addition of 10 mM persulfate, the OFL degradation efficiency reaches similar to 90% within 75 min, which is higher than efficiencies obtained for individual BaTiO3 , WS2 , or TiO3 , widely used photocatalysts in the field of water treatment. The boosted degradation efficiency can be ascribed to the promotion of charge carrier separation, resulting from the synergetic effect of the heterostructure and the piezoelectric field induced by the vibration. Moreover, the prepared composite displays good stability over five successive cycles of the degradation process. GC-MS analysis is used to survey the degradation pathway of OFL during the degradation process. Our results offer insight into strategies for preparing highly effective piezo-photocatalysts in the field of water purification.