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[Display omitted] Sunlight active CdS/BiOBr heterojunction photocatalyst was fabricated by a solvothermal route. To the best of our knowledge, the novelty of the research is based on the decoration of the hexagonal CdS nanoparticles on the surface of the tetragonal BiOBr microflowers for the creation of a heterostructure photocatalyst used for the removal of the antibiotics. The CdS/BiOBr-1:3 heterojunction exhibited 100% removal of norfloxacin and ciprofloxacin under simulated visible light. In addition, complete degradation of the antibiotics under natural sunlight was also achieved. Construction of the CdS/BiOBr heterojunction is a promising strategy for the improvement of photocatalytic performance due to a decrease in the charge carrier recombination rate at the interface, an increase in the visible light absorption range, and an enhancement of the surface area of the resultant product. The removal of the pollutants fit very well with the first-order reaction. The photogenerated hole played a crucial role in the removal of the antibiotics. Confirmation of the stability of the CdS/BiOBr heterojunction was also elucidated. The photoactivity of the photocatalyst remained the same after the fifth cycle implying the excellent cycling ability of the sample. This research demonstrates the promising potential of the CdS/BiOBr heterojunction for degradation of toxic antibiotics presented in water. [ABSTRACT FROM AUTHOR]

New strategy to create sunlight-active photocatalysts is a vital research topic in photocatalysis. In this work, ZnO/ZnS heterojunctions were fabricated very easily by thermal oxidation of hydrothermally grown ZnS in air. XRD, FT-IR, FESEM, TEM, XPS, XAS and PL results confirmed that ZnS-500 (ZnS calcined at 500 °C) contains the ZnO/ZnS heterojunctions. The ZnS-500 exhibited the highest photoactivity toward removal of azo dyes (reactive red 141, Congo red) and antibiotics (ofloxacin, norfloxacin) under natural sunlight. The combination of ZnS and ZnO enhances the photoactivity by suppressing the recombination of electron-hole pairs. The photodegradation of the organic contaminants followed pseudo-first order kinetics. The photocatalyst showed structural stability after five cycles. To understand the photocatalytic degradation mechanism, trapping experiment using various scavengers have been investigated. Photogenerated electrons are the crucial species involved in the degradation of the pollutant. It is also proposed that charge transfer at the ZnO/ZnS heterojunction is the Z-scheme type. This work provides a facile strategy for the interfacial engineering of heterojunctions with enhanced photocatalytic performance for environmental remediation. [Display omitted] • ZnO/ZnS photocatalyst was successfully fabricated by a thermal oxidation of hydrothermally grown ZnS in the air. • The enhanced photoactivity toward degradation of azo dyes and fluoroquinolone antibiotics was obtained. • The degradation of the pollutants followed the first-order kinetic model. • The prepared photocatalyst showed the excellent cycling ability after five times of use. [ABSTRACT FROM AUTHOR]

[Display omitted] • Ternary photocatalyst based on g-C 3 N 4 /BiOCl/CdS was successfully prepared. • The complete removal of oxytetracycline antibiotic under sunlight was achieved. • The photocatalyst shows good cycling ability with excellent structural stability for seven runs. • The photocatalytic degradation mechanism was proposed. One of the vital topics in photocatalysis research is the development of novel photocatalytic nanomaterials for degradation of toxic pollutants in the natural water under visible light irradiation. Herein we report, for the first time, a facile hydrothermal synthesis of g-C 3 N 4 /BiOCl/CdS heterojunction for complete removal of oxytetracycline (OTC) antibiotic in wastewater. The suppression of electron-hole recombination rate was obtained after creation of the ternary heterostructure. Accordingly, the enhanced photoactivity was found in the prepared heterojunction photocatalyst as expected. Complete removal of OTC was obtained under natural sunlight irradiation. The removal of OTC follows the first-order reaction with the maximum rate constant of 0.023 min−1. The prepared photocatalyst still maintains its structural stability with high photocatalytic performance even after seven times of use. Photogenerated holes are the crucial species involved in the OTC removal while electrons and hydroxyl radicals play a subordinate role. Charge transfer at the interface of the ternary heterojunction is proposed to be the Z-scheme type. The present work shows a promising strategy to create a novel ternary heterojunction with an enhanced photoactivity for complete detoxification of harmful OTC antibiotic in the environment. [ABSTRACT FROM AUTHOR]

A sunlight responsive WO 3 /AgBr heterojunction photocatalyst was prepared using hydrothermal and chemical precipitation methods. The photocatalyst with band gap of 2.93 eV exhibited high efficiency of 86% toward degradation Rhodamine B (RhB) dye under visible light. Interestingly, nearly complete degradation of RhB dye and ofloxacin (OFL) antibiotic under natural sunlight was achieved. Creation of the WO 3 /AgBr heterojunction is a promising strategy for enhancement of the photoactivity. This may be due to a decrease of charge carrier recombination rate at the interface and an increase in visible light absorption range of the resultant photocatalyst in comparison to those obtained from the pristine photocatalysts. Photogenerated hole plays the major role in photodegradation of the pollutant. The photocatalyst remains stable and still shows high efficiency after five consecutive cycles confirming its excellent cycling ability. This research demonstrates a promising performance of the sunlight active WO 3 /AgBr heterojunction photocatalyst for detoxification of dye and antibiotic in wastewater by utilization of an economical solar energy. [Display omitted] • A heterojunction photocatalyst based on WO3/AgBr was successfully prepared. • Complete removal of Rhodamine B (RhB) dye under natural solar light was achieved. • The photocatalytic degradation of both dye and antibiotic follows the first-order reaction. • The photocatalyst shows excellent structural stability and cycling ability after five cycles. [ABSTRACT FROM AUTHOR]