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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]

A novel photocatalyst composed of bismuth molybdate (Bi 2 MoO 6 , BMO) coupled with rhodium (Rh) nanoparticles was synthesized and evaluated for its efficiency in degrading dye contaminant under visible light irradiation. The BMO/Rh composite demonstrated a significant enhancement in photocatalytic performance, achieving a 40 % higher degradation rate of Rhodamine B (RhB) compared to bare BMO. Enhanced charge separation and reduced electron-hole recombination were primarily attributed to the synergistic effects introduced by the Rh nanoparticles. Extensive characterization techniques provided insights into the structural and mechanistic aspects of the photocatalyst. Stability tests confirmed that BMO/Rh maintained over 95 % of its initial activity after five consecutive reaction cycles, highlighting its durability. Scavenger experiments identified superoxide radicals (•O 2 -) and hydroxyl radicals (•OH) as the primary active species, contributing to the high efficiency of dye degradation. This study underscores the potential of BMO/Rh hybrids as sustainable and effective photocatalysts for environmental remediation. • Enhanced a BMO/Rh photocatalyst that improves dye degradation by 40 % under visible light. • Achieved improved charge separation with Rh nanoparticles, reducing electron-hole recombination. • Maintained over 95 % photocatalytic activity after five cycles, demonstrating high stability. • Quantified active radicals' roles in improving dye degradation efficiency. [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.

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]

Photocatalytic degradation of organic dyes in wastewater using visible light illumination is a green technology which requires efficient visible-light driven active catalytic material. For this, we have reported a novel visible light active Eu/WO 3 system with variation in europium contents (0, 2%, 4% and 6% Eu), which demonstrated enhanced photocatalytic activity for the degradation of various organic dyes including methylene blue (MB), methyl orange ((MO) and rhodamine B (RhB). Scanning electron microscopy (SEM), X-ray diffractometer (XRD), energy dispersive X-ray (EDX), UV–visible spectroscopy and photoluminescence (PL) spectroscopy were used for the characterization of nanostructures. The results showed that Eu has effective role in modifying the structural, morphological and optical properties of WO 3 photocatalyst. Moreover, the photocatalytic performance of WO 3 was improved due to incorporation of Eu. From results, it was seen that photocatalytic activity increases with increasing Eu concentration upto 4%, however, further increase in Eu concentration (6%) has decreased the performance under these condition for all dyes. The enhanced photocatalytic efficiency could be attributed to suppressed recombination of charge carriers and enhanced visible light absorption and increased BET surface area due to Eu doping into WO 3 photocatalyst. The as-synthesized nanostructures will be considered as a promising photocatalytic materials for the future research in this field. [ABSTRACT FROM AUTHOR]

In this paper, CeO 2 microplates were synthesized by a sol-gel auto-combustion method. AgI nanoparticles (NPs) were then deposited onto the surface of CeO 2 via a facile deposition–precipitation method. The as-prepared AgI/CeO 2 samples were characterized by various analytical techniques. The composites exhibited superior photocatalytic activities for the organic dyes (RhB) and the refractory pollutant (tetracycline (TC), a typical antibiotic) degradation under visible light irradiation. The CA-19.03 sample exhibited the highest photocatalytic activity. The enhanced photocatalytic performance could be ascribed to the improved separation of photogenerated charge carriers due to well-matched band structure. [ABSTRACT FROM AUTHOR]

Herein, we demonstrate a facile way of fabricating visible-light-active lanthanum and nitrogen – co-doped SrTiO 3 – TiO 2 heterostructured macroporous monolithic materials with bicontinuous morphology by impregnating strontium and lanthanum ions into a preformed porous TiO 2 gel in aqeuous solution containing urea followed by heat treatment in NH 3 atmosphere. The SrTiO 3 macroporous monolithic materials were formed by a solid-state reaction between the TiO 2 gel phase and precipitated SrCO 3 , while Sr 2+ was partially substituted with La 3+ ions. The SrCO 3 was precipitated within the TiO 2 wet gel by the reaction between impregnated Sr 2+ and CO 2 , which was produced by hydrolysis and decarbonation of a chelating agent in the TiO 2 wet gels and by hydrolysis of urea at 60 °C. X-ray powder diffraction studies showed that the incorporation of strontium, lanthanum, and nitrogen could effectively retard the phase transformation of TiO 2 from anatase to rutile and growth of crystallites. XPS analysis confirmed that lanthanum atoms were incorporated into the SrTiO 3 lattice by substituting strontium atoms, and nitrogen was incorporated in the TiO 2 lattice (i) substitutionally forming Ti – N-bonds and (ii) interstitially. The resultant lanthanum and nitrogen – co-doped SrTiO 3 - TiO 2 heterostructured monolithic materials retained a narrow macropore size distribution at the diameter ∼1.7 μ m. [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]

In this paper, CdS/TiO 2 heteronanofibers have been prepared for the photocatalysis toward organic dyes under visible irradiation. Firstly, the one dimensional (1D) TiO 2 porous nanofibers (50–100) nm in diameter and several micrometers in length were synthesized by electrospinning and then CdS nanopaticles (50–100 nm in size) successfully grown onto TiO 2 fibers to form the heterostructure. These CdS/TiO 2 heteronanofibers were adopted as photocatalyst and the photocatalsis processes were analyzed in detail, showing the enhanced visible photodecomposition and good recycle ability. Furthermore, the degradation kinetics was further investigated by varying the amount of CdS. The increase of CdS component may enhance the degradation rate under visible light, but the total degradation efficiency also is affected by the adsorption capacity of catalyst toward the dyes. With the improved visible light degradation performance, these CdS/TiO 2 heteronanofibers would be expected to be used in water purification. [ABSTRACT FROM AUTHOR]

A novel resin immobilized iron(II) phenanthroline [FePR] is prepared, characterized and exploited to understand C–C/C–O cleavage in Rhodamine B dye under visible light (λ ≥ 420 nm). Studies infer that both molecular oxygen and visible light are playing essential roles in photocatalysis, and pH is influencing the degradation. Photocatalysis by FePR involves oxo-iron ([Fe IV (phen) 3 = O]) species as reactive intermediate. LC–MS studies on the aliquots of partially photodegraded RhB reveal benzoic acid as a main degradation product; however, complete degradation was achieved under optimum condition. Overall, the FePR is a stable heterogeneous photocatalyst, which can be used for advanced oxidative process in greener route. [ABSTRACT FROM AUTHOR]