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The construction of a Z-scheme heterojunction favors the improvement of the photocatalytic activity of photocatalysts. Herein, the LaVO 4 /Bi 3 O 4 Cl Z-scheme heterojunction was designed reasonably by the method of in situ growth. The obtained heterojunction was further used as a photocatalyst for the degradation of ofloxacin (OFX), an antibiotic, in wastewater. The degradation efficiency of OFX by the optimal sample (LBC-2) was 94.3 % and the values of k were about 114.7 and 2.4 times those of LaVO 4 and Bi 3 O 4 Cl, respectively. In addition, LBC-2 maintained high activity after 4 cycles. The significantly reduced recombination rate of carriers in LBC-2 was reflected by the results of the photoluminescence (PL), photocurrent (PC), and electrochemical impedance spectroscopy (EIS) studies. The degradation pathways of OFX were proposed accounting to the intermediates detected by liquid chromatography-mass spectroscopy (LC-MS). Toxicity estimations showed that the toxicity of some intermediates decreased. This work provides new insight into the development of Z-scheme photocatalysts for the removal of antibiotics as pollutants. • Novel Z-scheme LaVO 4 /Bi 3 O 4 Cl composite photocatalysts were synthesized. • LaVO 4 /Bi 3 O 4 Cl composites exhibited excellent activity for ofloxacin degradation. • The apparent rate constant for ofloxacin degradation was about 114.7 and 2.4 times as that of LaVO 4 and Bi 3 O 4 Cl. • Z-scheme heterojunction boosted the fast transfer of charge carriers. • The degradation pathway of ofloxacin was deduced. [ABSTRACT FROM AUTHOR]

In the present work, a series of layered BiOBr/g-C 3 N 4 heterojunction photocatalysts were prepared via a simple reflux process, and their photocatalytic performance was investigated by the degradation of rhodamine B (RhB) and bisphenol A (BPA) under visible light irradiation. It was found that BiOBr nanoplates were deposited on the external surface of g-C 3 N 4 nanosheets (CNNS) and the tightly contacted interface was formed between two components, giving rise to a 2D porous layered heterojunction structure with a high specific area. It was found that BiOBr nanoplates coupled with the proper amount of CNNS exhibited an excellent photocatalytic performance due to the combined effects of layered heterojunction, high specific surface area and porous structure, which lead to the high efficiency of light harvesting and charge separation. The active species of OH is the most crucial one while h + and O 2 − contributed to a lesser extent in RhB and BPA photocatalytic degradation. Based on the direct evidence of the formed OH, O 2 − and h + active species detected by active species capture experiment and ESR spectra, a Z-scheme photocatalytic mechanism was proposed for the charge separation. The present work may provide an insight for designing novel layered Z-scheme heterojunction photocatalysts with a high performance. [ABSTRACT FROM AUTHOR]