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The development of highly active photocatalysts with broad spectrum response is of paramount importance for photocatalytic applications. Herein, heterostructured CuO-Cu 2 O/ZnO photocatalysts were prepared in a single step and under mild conditions using a photodeposition process which allows to deposit CuO-Cu 2 O particles with an average size of ca. 2.4 nm on the surface of ZnO nanorods. The p-n heterojunction built between CuO-Cu 2 O and ZnO allows to increase both the visible light response of the photocatalyst and the charge separation. The CuO-Cu 2 O(10%)/ZnO catalyst exhibits the highest activity for the degradation of dyes (Rhodamine B and Remazol Brilliant Blue R) and of Naproxen under simulated solar light irradiation. Based on scavenging experiments, holes, superoxide radicals O 2 ●- and singlet oxygen 1O 2 are the dominant species involved in the photocatalytic degradation and a mechanism is proposed. Due to its high stability and photocatalytic performance in various water matrices, the CuO-Cu 2 O(10%)/ZnO nanohybrid is of high potential for the large scale remediation of organic pollutants in wastewater. [Display omitted] • Facile photodeposition method to associate CuO-Cu 2 O nanoparticles with ZnO NRs. • The CuO-Cu 2 O(10%)/ZnO photocatalyst shows the highest activity for the degradation of emerging pollutants. • The Naproxen photocatalytic degradation was investigated. • The CuO-Cu 2 O(10%)/ZnO photocatalyst is of high potential for wastewater treatment. [ABSTRACT FROM AUTHOR]

A series of heterostructured photocatalysts associating reduced graphene oxide (rGO) and BiOBr sheets with exposed {001} facets were prepared via a hydrothermal method. TEM experiments demonstrate that rGO deposits at the surface of BiOBr sheets to yield shell/core rGO/BiOBr particles. Under visible light irradiation, the rGO (1%)/BiOBr photocatalyst exhibits the highest activity for the degradation of the Orange II dye and for the removal of acetaminophen. This originates from the increased visible light absorption and from the effective separation of charge carriers in rGO/BiOBr composites. Investigations into the photocatalytic mechanism show that holes in the valence band of BiOBr and superoxide O 2 − radicals generated by the photocatalyst are the main species responsible for the oxidation of acetaminophen. The rGO (1%)/BiOBr catalyst was also demonstrated to be of high stability, further highlighting its potential for practical photocatalytic applications. Unlabelled Image • Shell/core rGO/BiOBr composites were synthesized by a hydrothermal method. • The rGO (1%)/BiOBr catalyst exhibits high activity for the degradation of Orange II and acetaminophen. • The coupling of rGO with BiOBr allows effective charge carriers separation. [ABSTRACT FROM AUTHOR]

The preparation of heterostructured photocatalysts associating BiOBr, reduced graphene oxide (rGO) and zinc tetracarboxyphthalocyanine (ZnPc(CO 2 H) 4) and their performance for the degradation of the Orange II dye and of phenol are reported. The BiOBr/rGO/ZnPc(CO 2 H) 4 (0.25) photocatalyst displays a superior activity than BiOBr and BiOBr/rGO, indicating that ZnPc(CO 2 H) 4 enhances both the visible light absorption and the charge carrier separation, which is confirmed by photoluminescence, photocurrent responses and electrochemical impedance spectroscopy Nyquist plots. Scavenging experiments show that the main active species involved in the degradation of Orange II and phenol are superoxide radicals and holes and a mechanism is proposed. Due to its high stability, the BiOBr/rGO/ZnPc(CO 2 H) 4 (0.25) catalyst shows high potential for real environmental remediation. [Display omitted] • ZnPc(CO 2 H) 4 was easily associated to BiOBr/rGO by sonication. • High photocatalytic activity owing to the synergy between ZnPc(CO 2 H) 4 and BiOBr/rGO. • Enhanced visible light absorption and charge separation result in improved photoactivity. • The BiOBr/rGO/ZnPc(CO 2 H) 4 photocatalyst is stable and can be reused up to 10 times. [ABSTRACT FROM AUTHOR]