Effects of active species on degrading A-ring of tetracycline in the Z-scheme heterostructured core-shell La(OH)(3)@BaTiO3 composition

摘要

It has been found it more difficult in completely degrading A-ring of tetracycline (TC) than completely degrading B-D rings of tetracycline. Thus, it is very necessary to find an effective route to completely degrading A-ring of tetracycline. In this work, a Z-scheme heterojuncted core-shell La(OH)(3)@BaTiO3 composite (LB) was designed and fabricated through hydrothermal method. Many characterization techniques were employed to investigate the microstructure, phases, composition, energy band structure, and the lifetime of photogenerated carriers. In the mean time, the photocatalytic properties, including the degradation of A-ring and B-D rings of TC, as well as active species during photodegradation were investigated. It is found that the as-prepared LB has an improved lifetime of photoproduced carriers, as well as high photocatalytic properties, being attributed to the core-shell structured heterojunction La(OH)(3)@BaTiO3. In addition, it is also found that center dot O-2(-) is more effective on degrading A-ring of TC than other active species, likely owed to the PKa3 value (3.3) of A-ring in TC. This work has supplied a route to completely degrading the A-ring of TC: rationally design and prepare a Z-scheme heterojuncted composites which supply very negative conduction band bottom potential. (C) 2019 Elsevier B.V. All rights reserved.