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[Display omitted] The exploration of emerging photocatalysts like covalent organic frameworks (COFs) is an essential but challenging endeavor to find sustainable solutions for selective organic transformations. Anthraquinones are envisaged to construct COFs for visible light photocatalysis because their derivatives are employed industrially as oxidation catalysts or organic dyes. Herein, an anthraquinone COF, TpAQ-COF, is successfully constructed with 1,3,5-triformylphloroglucinol (Tp) and 2,6-diaminoanthraquinone (AQ). Then, the selective oxidation of amines over TpAQ-COF is implemented. Amines can be effectively converted into corresponding imines over TpAQ-COF powered with green light and oxygen, during which superoxide radical anion is discerned as the pivotal reactive oxygen species. This work suggests that COFs could inherit the advantages of molecular building blocks for selective reactions powered with broad visible light. [ABSTRACT FROM AUTHOR]

To simulate natural photosynthesis, scientists have developed an artificial Z-scheme system that splits water into hydrogen and oxygen using two different semiconductors. Researchers are striving to improve the performance of Z-scheme systems by improving light absorption, developing redox couples with high stability, and finding new cocatalysts. Here, we report the synthesis and utilization of LaFeO3/g-C3N4 as a Z-scheme system for water reduction to produce hydrogen and organic dye degradation under visible light irradiation. The as-fabricated photocatalyst revealed exceptional activity for H2 production (i.e., 351 µmol h−1g−1), which is 14.6 times higher compared to that of the single-component g-C3N4 (i.e., 24 µmol h−1g−1). In addition, the composite photocatalyst degraded 87% of Methylene Blue (MB) and 94% of Rhodamine B (RhB) in 2 h. Various experimental analyses confirmed that the exceptional performance of the LaFeO3/g-C3N4 Z-scheme catalyst is due to remarkably enhanced charge carrier separation and improved light absorption. The development of this highly effective Z-scheme heterostructure photocatalyst will pave the way for the sustainable development of newly designed Z-scheme scheme systems that will tackle energy and environmental crises. [ABSTRACT FROM AUTHOR]

The construction of a p-n heterojunction photocatalyst manage to conquer the setbacks of low photocatalytic activity caused by rapid charge recombination and precarious photo-response range. Herein, an interlayer of expanded MoS 2 coupled with Bi 2 WO 6 (BW-IEM) photocatalyst was synthesized for removal of Methylene Blue (MB) up to 97% (5.18 ×10−2 min−1) under irradiation of low power 1 W LED white light. The outstanding photocatalytic performance of the p-n heterojunctions BW-IEM photocatalyst is mainly attributed to the enhancement of light harvesting, improvement in the separation of charge carriers, and coexistence of oxygen vacancy. The main reactive oxygen species (ROS) responsible for the photodegradation of MB were •O 2 - radicals and •OH. This work provides a new strategy for the potential IEM photocatalyst as a matrix in a p-n heterojunction composite. [Display omitted] • p-n heterojunctions of interlayer expanded MoS 2 coupled with Bi 2 WO 6. • 4% BW-IEM shows excellent LED white light driven photocatalytic activity. • Bi 2 WO 6 and oxygen vacancy enhances the separation of photogenerated carries. • •O 2 - and •OH radicals are the main reactive oxygen species. [ABSTRACT FROM AUTHOR]

The present work demonstrates a facile hydrothermal synthesis of Plasmonic Au–TiO 2 nanocatalyst followed by its successful application for complete photocatalytic dye degradation (oxidation) in batch and continuous flow process under natural sunlight as well as visible and UV light. The Au-TiO 2 nanocatalyst was synthesized by a hydrothermal method at basic pH conditions. It was meticulously analyzed by a variety of spectroscopic (UV-Vis, Raman, FTIR, PL, Powder XRD, ED-XRF, XPS), microscopic (FE-SEM with elemental mapping, TEM), and thermal (DSC) techniques. The characterization results showed that monodisperse Plasmonic Au(0) nanoparticles with a mean diameter of 12 ± 1 nm are homogeneously deposited on Anatase TiO 2 crystals. The nanocatalyst showed complete photocatalytic degradation of various dye compounds (Eosin Yellowish, Indigo Carmine, Methyl Orange, Methylene Blue, and Rhodamine B) under visible light or sunlight as confirmed through UV-Vis spectra, mass spectral study, and TOC analysis of dye solutions. A continuous flow process using a specially designed photoreactor was accomplished with a long catalyst lifespan, easy processibility, and low cost. Easy synthesis of the catalyst, its very detailed characterization, and its efficient catalytic studies to completely degrade various dye molecules under visible light source in the absence of any added oxidizer (O 2 , H 2 O 2 , KMnO 4 , Organic peroxides) and the demonstration of continuous flow process are significant highlights of the present work. A plausible mechanistic pathway is also presented in line with the previous literature reports and presently observed phenomenon. [Display omitted] [ABSTRACT FROM AUTHOR]