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The construction of heterojunction photocatalysts is an excellent strategy for treating wastewater. Herein, a three-dimensional nanoflower-like TiO 2 /WO 3 heterojunction photocatalyst was synthesized in situ on the surface of pure Ti substrate by plasma electrolyte oxidation (PEO) combined with a subsequent process, and the abundant network topology and lattice defects improved the adsorption performance of the photocatalyst. The construction of Z-scheme heterojunction not only promotes the separation of photogenerated carriers, but also enhances the light absorption ability and greatly improves the photocatalytic performance of photocatalysts. Under the synergistic effect of adsorption and photocatalysis, the degradation rate of MB reached 86.2 % in 2 h, which was significantly higher than that of the single-component photocatalyst. Finally, the synthesis of TiO 2 /WO 3 heterojunction photocatalysts by this process and the reaction mechanism of heterojunction photocatalysts for the degradation of organic dyes were illustrated by combining experiments and DFT calculations. In conclusion, this study opens up a new process for synthesizing Z-scheme heterojunction photocatalysts, which brings new insights for photocatalytic treatment of water pollution. [ABSTRACT FROM AUTHOR]

The structural uniqueness of covalent organic frameworks (COFs) has brought great potential for their applications in photocatalysis. Two novel azo‐linked COFs AZO‐B‐COF and AZO‐T‐COF were successfully constructed by the monomer exchange method. Significantly, two as‐synthesized azo COFs presented a much higher photodegradation rate of 96 % and 51 % for AZO‐T‐COF and AZO‐B‐COF, respectively, which was in sharp contrast to the almost 0 degradation rate of imine COFs. And as expected, AZO‐T‐COF could be cycled at least 5 runs without a significant decrease in catalytic efficiency. Systematical experiments and theoretical calculations showed that comparing with imine COFs, conjugated structure of azo COFs broadened the visible‐light absorption range and improved the transfer efficiency of the photocarriers. The N‐rich azo bonds acted as an electron acceptor and made the materials better planarity. This work not only enriches COFs family but also demonstrated the superiority of azo‐linked COFs. [ABSTRACT FROM AUTHOR]

The presented study was focused on the simple, eco-friendly synthesis of composite hydrogels of crosslinked carboxymethyl cellulose (CMC)/alginate (SA) with encapsulated g-C3N4 nanoparticles. The structural, textural, morphological, optical, and mechanical properties were determined using different methods. The encapsulation of g-C3N4 into CMC/SA copolymer resulted in the formation of composite hydrogels with a coherent structure, enhanced porosity, excellent photostability, and good adhesion. The ability of composite hydrogels to eliminate structurally different dyes with the same or opposite charge properties (cationic Methylene Blue and anionic Orange G and Remazol Brilliant Blue R) in both single- and binary-dye systems was examined through adsorption and photocatalytic reactions. The interactions between the dyes and g-C3N4 and the negatively charged CMC/SA copolymers had a notable influence on both the adsorption capacity and photodegradation efficiency of the prepared composites. Scavenger studies and leaching tests were conducted to gain insights into the primary reactive species and to assess the stability and long-term performance of the g-C3N4/CMC/SA beads. The commendable photocatalytic activity and excellent recyclability, coupled with the elimination of costly catalyst separation requirements, render the g-C3N4/CMC/SA composite hydrogels cost-effective and environmentally friendly materials, and strongly support their selection for tackling environmental pollution issues. [ABSTRACT FROM AUTHOR]

Repurposing enzymes to catalyze non‐natural asymmetric transformations that are difficult to achieve using traditional chemical methods is of significant importance. Although radical C−O bond formation has emerged as a powerful approach for constructing oxygen‐containing compounds, controlling the stereochemistry poses a great challenge. Here we present the development of a dual bio‐/photo‐catalytic system comprising an ene‐reductase and an organic dye for achieving stereoselective lactonizations. By integrating directed evolution and photoinduced single electron oxidation, we repurposed engineered ene‐reductases to steer non‐natural radical C−O formations (one C−O bond for hydrolactonizations and lactonization‐alkylations while two C−O bonds for lactonization‐oxygenations). This dual catalysis gave a new approach to a diverse array of enantioenhanced 5‐ and 6‐membered lactones with vicinal stereocenters, part of which bears a quaternary stereocenter (up to 99 % enantiomeric excess, up to 12.9 : 1 diastereomeric ratio). Detailed mechanistic studies, including computational simulations, uncovered the synergistic effect of the enzyme and the externally added organophotoredox catalyst Rh6G. [ABSTRACT FROM AUTHOR]

Photocatalysis, mainly using TiO2 as a catalyst, has emerged as a promising method to address the issue of wastewater treatment. This study explores the enhanced photocatalytic activity of TiO2 through the introduction of reduced graphene oxide (rGO) and cadmium sulfide (CdS) as selective metal dopants. The incorporation of rGO and CdS into the TiO2 lattice aims to optimize its photocatalytic properties, including bandgap engineering, charge carrier separation, and surface reactivity. The unique combination of CdS and rGO with TiO2 is expected to boost degradation efficiency and reduce the reliance on expensive and potentially harmful sensitizers. This experimental investigation involves the synthesis and characterization of TiO2-based photocatalysts. The photocatalytic degradation of methyl orange (MO) and methylene blue (MB) was assessed under controlled laboratory conditions, studying the influence of metal dopants on degradation kinetics and degradation efficiency. Furthermore, the synthesized photocatalyst is characterized by advanced techniques, including BET, SEM, TEM, XRD, and XPS analyses. The degraded samples were analyzed by UV-Vis spectroscopy. Insights into the photoexcitation and charge transfer processes shed light on the role of metal dopants in enhancing photocatalytic performance. The results demonstrate the potential of a TiO2-rGO-CdS-based photocatalyst in which 100% degradation was achieved within four hours for MO and six hours for MB, confirming efficient azo dye degradation. The findings contribute to understanding the fundamental principles underlying the photocatalytic process and provide valuable guidance for designing and optimizing advanced photocatalytic systems. Ultimately, this research contributes to the development of sustainable and effective technologies for removing azo dyes from various wastewaters, promoting environmental preservation and human well-being. [ABSTRACT FROM AUTHOR]

The release of industrial effluents into fresh water is a major contributor of water contamination. Therefore, it is highly desirable to develop a viable solution to this alarming issue to improve the quality of clean water. To enhance the photocatalytic efficiency and hence utilization ratio of CuO, a series of CuO–FeSe2 composites with different varying contents of FeSe2 were prepared through facile synthetic methods. X-ray diffraction (XRD) and energy-dispersive X-rays (EDX) analysis verified that the samples were successfully prepared without any contaminating phases. The average crystallite sizes of CuO and FeSe2 were computed to be 29 and 21 nm respectively. For the CuO–FeSe2 composites, the crystallite sizes varied between 25 and 27 nm. The morphology of CuO was comprised of needle-shaped structures, whereas that of FeSe2 was observed to be flower-shaped structures comprising of irregular crystals. A red shift in the bandgap of CuO–FeSe2 composites was observed with the increase in FeSe2 concentration. The prepared photocatalysts were utilized to evaluate their efficiency under visible light against Rhodamine B (RhB). Among all the prepared composites, CuO–75% FeSe2 revealed a remarkable performance and degraded 96% RhB in 180 min. Rate constants for the degradation of the dye were determined by applying the Langmuir–Hinshelwood model. [ABSTRACT FROM AUTHOR]

Magnetic separation of photocatalysts holds great promise for water treatment. A magnetic separation method has a positive effect on the recovery of catalysts after degradation. In this paper, an efficient and reusable catalytic system is developed based on coating magnetic Fe3O4 by depositing Fe2+ on the surface of ZnO. The Fe3O4/ZnO nanocomposite exhibits enhanced performance for organic pollutant degradation. The Fe3O4/ZnO system demonstrates a high photocatalytic activity of 100% degradation efficiency in Rhodamine B (RhB) degradation under UV light irradiation for 50 min. The excellent photocatalytic activity is primarily due to the separation of photogenerated electron-hole pairs being facilitated by the strong interaction between Fe3O4 and ZnO. The induction of the magnetic Fe3O4 endows the Fe3O4/ZnO composite with superior magnetic separation capability from water. Experiments with different radical scavengers revealed that the hydroxyl radical (·OH) is the key reactive radical for the effective degradation of RhB. This work innovatively affords a common interfacial dopant deposition strategy for catalytic application in the degradation of organic dye pollutants and catalyst separation from wastewater efficiently. [ABSTRACT FROM AUTHOR]

This study explores the use of Halloysite NanoTubes (HNTs) as photocatalysts capable of decomposing organic dyes under exposure to visible or ultraviolet light. Through a systematic series of photocatalytic experiments, we unveil that the photodegradation of Rhodamine B, used as a model cationic dye, is significantly accelerated in the presence of HNTs. We observe that the extent of RhB photocatalytic degradation in 100 min in the presence of the HNTs is ~four times higher compared to that of bare RhB. Moreover, under optimized conditions, the as-extracted photodegradation rate of RhB (~0.0022 min−1) is comparable to that of the previously reported work on the photodegradation of RhB in the presence of tubular nanostructures. A parallel effect is observed for anionic Coumarin photodegradation, albeit less efficiently. Our analysis attributes this discrepancy to the distinct charge states of the two dyes, influencing their attachment sites on HNTs. Cationic Rhodamine B molecules preferentially attach to the outer surface of HNTs, while anionic Coumarin molecules tend to attach to the inner surface. By leveraging the unique properties of HNTs, a family of naturally occurring nanotube structures, this research offers valuable insights for optimizing photocatalytic systems in the pursuit of effective and eco-friendly solutions for environmental remediation. [ABSTRACT FROM AUTHOR]

Water pollutants of non-biodegradable toxic aromatic dye including Methylene blue (MB) and Rhodamine (RhB) are extremely carcinogenic thiazines used in various industries such as leather industry, paper industry, and the dyeing industry. The presence of dyes in wastewater causes severe threats to human health that are responsible for various harmful chronic or acute diseases and also shows an adverse impact on the environment as it reduces transparency and is harmful to water microorganisms. To overcome severe issues, many traditional techniques have been used to remove toxic pollutants, but these methods are insufficient to remove chemically stable dyes that remain in the treated wastewater. However, the photocatalytic degradation process is an efficient approach to degrade the dye up to the maximum extent with improved efficiency. Therefore, in this work, a new class of two-dimensional (2D) transition metal carbide of Titanium Carbide (Ti3C2Tx) MXene material was used for the organic dyes degradation such as MB and RhB using a photocatalytic process. A layered structure of hexagonal lattice symmetry of Ti3C2Tx MXene was successfully synthesized from the Titanium Aluminum Carbide of Ti3AlC2 bulk phase using an exfoliation process. Further, the XRD spectrum confirms the transformation of bulk MAX phase having (002) plane at 9.2° to Ti3C2Tx MXene of (002) plane at 8.88° confirms the successful removal of Al layer from MAX phase. A smooth, transparent, thin sheet-like morphology of Ti3C2Tx nanosheet size were found to be in the range of 70 to 150 nm evaluated from TEM images. Also, no holes or damages in the thin sheets were found after the treatment with strong hydrofluoric acid confirms the formation Ti3C2Tx layered sheets. The synthesized Ti3C2Tx MXene possesses excellent photocatalytic activity for the degradation of dyes MB, RhB, and mixtures of MB and RhB dyes. MB dye degraded with a degradation percentage efficiency of 99.32% in 30 min, while RhB dye was degraded upto 98.9% in 30 min. Also, experiments were conducted for degradation of mixture of MB and RhB dyes by UV light, and the degradation percentage efficiency were found to be 98.9% and 99.75% for mixture of MB and RhB dye in 45 min, respectively. Moreover, reaction rate constant (k) was determined for each dye of MB, RhB, and mixtures of MB and RhB and was found to be 0.0215 min−1 and 0.0058 min−1, and for mixtures, it was 0.0020 min−1 and 0.009 min−1, respectively. [ABSTRACT FROM AUTHOR]

Water, essential for all life, faces contamination challenges due to industrialization and unchecked urban development, producing pollutants such as organic dyes, detergents, heavy metals, and pesticides. This has emerged as one of the most pressing environmental concerns in recent years, with a particular emphasis on organic dyes due to their demonstrated health-related concerns. In this context, this paper reviews the use of photocatalysis as a wastewater treatment method, highlighting its significant potential for removing organic dyes from aqueous solutions. Additionally, the focus is on the design, development, performance enhancement, and overall research progress in fabricating graphene-based semiconductor nanocomposites as photocatalysts. Representative examples are discussed, emphasizing the potential of these nanocomposites in degrading toxic organic dyes through photocatalysis. The enhanced photoactivity is attributed to the synergistic effects of graphene and semiconductor materials, leading to improved light absorption, charge separation, and reactive oxygen species generation. This comprehensive review provides valuable insights to advance wastewater treatment technologies and address environmental impacts caused by organic dye pollution. [ABSTRACT FROM AUTHOR]

In this paper, three-dimensional TiO2 nanoflowers (NFs) were prepared by a facile hydrothermal method, and Ag3PO4 was grown in situ following alkali treatment to design and synthesize a Ag3PO4/OH/TiO2 catalyst with excellent photocatalytic activity under visible light. The test results show that the photocatalytic degradation performance of TiO2 NFs after alkali treatment and Ag3PO4 loading is significantly improved. This is because the alkali treatment and the introduction of Ag3PO4 can provide a large amount of –OH, which can be converted to ˙OH under UV irradiation, followed by an increase in the number of active radicals to enhance the photocatalytic degradation performance. Meanwhile, the introduction of Ag3PO4 can effectively improve the light absorption ability of the photocatalyst. Moreover, the in situ growth of Ag3PO4 on TiO2 NFs can construct a high-quality Ag3PO4/TiO2 heterojunction to promote the charge separation and transport. Therefore, the degradation rate of Ag3PO4/OH/TiO2 can reach 90% after 30 min for degrading 3 mg L−1 RhB under visible light. The Ag3PO4/OH/TiO2 photocatalyst designed in the present work provides a new tool for the degradation of organic dyes. [ABSTRACT FROM AUTHOR]

Recently, visible-light-driven photocatalysis attracts much concerns in the remediation of environmental organic pollutants. In this study, the cerium doped biochar was fabricated through the hydrothermal method, and served as an efficient photocatalyst towards rhodamine B degradation under visible light irradiation. Almost 100% of rhodamine B was removed by 2.0 g·L−1 cerium doped biochar after 60 min of visible light irradiation at pH 3, but only about 25.50% and 29.60% of rhodamine B was removed by cerium dioxide and biochar under identical conditions. The degradation process coincided well with the pseudo-first-order kinetic model, and the photodegradation rate constant of cerium doped biochar was 0.0485·min−1, which was respectively 97 and 44 times that of biochar (0.0005·min−1) and cerium dioxide (0.0011·min−1). According to the trapping experiments and electron spin resonance spectroscopy analysis, h+, O2−∙ and ∙OH all participated in the degradation of rhodamine B in the cerium doped biochar photocatalytic systems, and the function of h+ and ∙OH was dominated. Consequently, the biochar could not only be an excellent carrier for supporting cerium dioxide, but also greatly improved its photocatalytic activity. The band gap of cerium doped biochar was narrower than cerium dioxide, which could improve the separation and migration of photogenerated electron–hole pairs under visible-light excitation, thus ultimately enhanced the degradation of rhodamine B. This work provided a deeper understanding of the preparation of biochar-based photocatalyst and its application in the remediation of environmental organic pollution. [ABSTRACT FROM AUTHOR]

In the current research, new metal complexes have been synthesized by using the greener synthetic approach in which 3‐Nitroaniline reacts with the elements of group‐IIB and group‐IVB. According to this method, ligand and metals were dissolved in 1,4‐dioxane and stirred at room temperature for a specific time period. The method for the preparation of metal‐base complexes is quite simple and cost‐effective. To identify the synthesized compounds various physio‐chemical analytical techniques were used such as Melting point, FT‐Raman Spectroscopy, FT‐IR Spectroscopy, Thermogravimetric analysis, and Scanning electron microscope (SEM) that provide significant data about the general structural characteristics of synthesized compounds. The percentage degradation efficiency of synthetic dyes was obtained as 57 %, 66 %, and 97 % using the synthesized compounds as photocatalysts. A statistical tool, RSM was used for the optimization of parameters (Concentration of Dye, Dose of Catalyst, and contact time). [ABSTRACT FROM AUTHOR]

Metal-organic frameworks (MOFs) are emerging as pivotal porous crystalline materials with diverse applications. Typically, MOFs are synthesized using solvothermal techniques at high temperatures and pressures. In this study, a novel approach was employed to synthesize zinc-based MOFs, specifically MOF-5, at low temperatures (up to 50 °C) via chemical mixing at standard pressures. Varying the temperature and solvents, N-methyl-2-pyrrolidone (NMP) and N,N-dimethylformamide (DMF), in the chemical mixing process, the highest yield of the material was observed with DMF at 50 °C (M1). Two additional samples, M2 and M3, are synthesized at room temperature using DMF and NMP, respectively. Despite similarities in XRD, Raman, and FTIR analyses confirming successful MOF-5 formation, noticeable differences in sample morphology arise due to distinct synthesis conditions, particularly solvent and temperature variations. The MOF-5 samples exhibit UV absorption with varying band gaps. Notably, when employed as photocatalysts for organic dye (methylene blue) degradation, M2 outperforms others, achieving an impressive 85% degradation under simulated solar light irradiation. This work underscores the significance of tuning MOF photocatalyst properties through tailored synthesis routes, recognizing the profound impact of morphology and elemental composition on enhancing photocatalytic dye degradation performance. [ABSTRACT FROM AUTHOR]

Tribocatalysis is one of the emerging processes for organic dye degradation application. The process uses mechanical energy as a source for breaking down organic pollutants present in water. The synergistic effect of two catalysis processes for eliminating organic pollutants, here in the present study photocatalysis an advanced oxidation process is integrated with the tribocatalysis process for enhancing the degradation efficiency of the tribocatalysis process by using BaTiO3 ceramic powder as a catalyst. The responsible factors for dye degradation via the tribocatalysis process such as surface roughness of the materials utilized, force applied, and energy band gap of the catalyst are also studied. The Methylene Blue dye's degradation was ~39%, ~60%, and ~76% through tribocatalysis, photocatalysis, and photo-tribocatalysis respectively by using 400 mg BaTiO3 ceramic powder in 8 h. The synergistic effect of photocatalysis and tribocatalysis process showed enhanced degradation compared to individual processes. [ABSTRACT FROM AUTHOR]

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Developing novel eco-friendly broad-spectrum visible light photocatalysts for dye removal is one of the urgent problems for water treatment. Here, copper-doped carbon dots (CDs) were reported to be directly fabricated from chromated copper arsenate (CCA) wood waste for the photocatalytic degradation of the methylene blue dye. The properties of the resulting CDs were thoroughly characterized and analyzed, preceding an investigation into the adsorption kinetics of dye degradation. The kinetic study showed that reactant concentration was the rate-limiting factor. The obtained CDs showed a 151 mg/g photocatalytic degradation capacity. Comparing pure CDs to CDs/TiO2 composites, the former demonstrated higher photodegradation efficiency. This superiority can be attributed to the synergistic action of adsorption and photocatalytic degradation working in tandem. This study prepared Cu doped CDs and elucidated the photocatalysis mechanism of methylene blue degradation by CDs. The photodegradation of organic dyes through CDs derived from waste CCA wood emerges as an eco-friendly, facile, and highly efficient method. [ABSTRACT FROM AUTHOR]

Over the past decade, safeguarding marine life and aquatic ecosystems against deleterious dye pollutants has emerged as a paramount concern. Methylene blue dye stands out as one such pollutant capable of inflicting irreversible damage to marine ecosystems even at minute concentrations. Addressing this pressing issue, we synthesized a novel CoMnFe2O4/graphene oxide nanocomposite employing a microwave-ultrasonic method. This composite, comprising soft superparamagnetic CoMnFe2O4 hollow microstructures integrated onto graphene oxide surfaces, revealed a mesoporous structure with a notably high surface area, which was about 96.4654 m2.g−1. Various analytical techniques were employed to scrutinize the crystal structure, functional groups, surface chemical composition, and morphologies of the synthesized CoMnFe2O4/graphene oxide nanocomposite (X-ray diffraction, Fourier-Transform Infrared Spectroscopy, energy-dispersive X-ray spectroscopy, field emission scanning electron microscopy, and high-resolution transmission electron microscopy). The CoMnFe2O4 crystal phase appears to be cubic in the X-ray diffraction with a 28.91 nm Avg. crystallite size. The measured band gap energies for the CoMnFe2O4, graphene oxide, and CoMnFe2O4/graphene oxide nanocomposite are 2.23 eV, 2.90 eV, and 1.89 eV, respectively. Remarkably, under visible light irradiation, the nanocomposite exhibited an impressive degradation efficiency of 97.54 % within just fifty minutes (at pH = 7, Methylene blue conc. = 15 mg/L, and catalyst dose = 0.05 g.), attributed to a photo degradation rate constant (k value) reaching 0.07330 min−1. Notably, this efficiency nearly doubled with the introduction of H2O2 peroxide. The outstanding recyclability of the CoMnFe2O4/graphene oxide nanocomposite, sustaining optimal performance over four cycles without significant degradation, underscores its potential for long-term environmental remediation efforts. Moreover, its magnetic extractability from contaminated solutions enhances its suitability for advanced environmental applications.

Synthetic dyes are widely used in various industries, which inevitably leads to increased water pollution. One of the recognized and waste-free techniques for water treatment is photocatalytic purification using semiconductor nanoparticles. However, the debate on how photocatalytic properties can be tuned through structural and morphological parameters using nanoparticle synthesis procedures remains open. In the present work, an approach to regulate UV-light-driven photocatalytic activity of spherical SnO2 nanoparticles using different structural parameters is demonstrated for the first time. Complex characterization of nanoparticles was provided using physicochemical methods with the help of computational methods. Special attention was paid to the development of a protocol of oxygen vacancy accounting within computer calculations for more realistic modeling of the interaction energy between nanoparticle surfaces and organic dye molecules of different natures. The photocatalysis mechanism was investigated according to the developed protocol, including the study of dye mixture kinetic degradation, dye-photocatalyst complex formation, and the ratio of oxygen vacancies and defects. It was shown that 93% of single dye decomposed in 7 min, and degradation of the dye mixture in a real water sample from Neva River achieved 60% after 40 min. It was possible to establish that this proof-of-concept study based on the combination of experimental and computational approaches can help develop the strategy of the rational design of photocatalysts promising for purification of real water samples. [ABSTRACT FROM AUTHOR]

Inorganic‐organic hybrid materials are a kind of multiduty materials with high crystallinity and definite structures, built from functional inorganic and organic components with highly tunable photochemical properties. Perylenediimides (PDIs) are a kind of strong visible light‐absorbing organic dyes with π‐electron‐deficient planes and photochemical properties depending on their micro‐environment, which provides a platform for designing tunable and efficient hybrid photocatalytic materials. Herein, four radical‐doped PDI‐based crystalline hybrid materials, Cl4‐PDI⋅SiW12O40 (1), Cl4‐PDI⋅SiMo12O40 (2), Cl4‐PDI⋅PW12O40 (3), and Cl4‐PDI⋅PMo12O40 (4), were attained by slow diffusion of polyoxometalates (POMs) into acidified Cl4‐PDI solutions. The obtained PDI‐based crystalline hybrid materials not only exhibited prominent photochromism, but also possessed reactive organic radicals under ambient conditions. Furthermore, all hybrid materials could be easily photoreduced to their radical anions (Cl4‐PDI⋅−), and then underwent a second photoexcitation to form energetic excited state radical anions (Cl4‐PDI⋅−*). However, experiments and theoretical calculations demonstrated that the formed energetic Cl4‐PDI⋅−* showed unusual POM‐dependent photocatalytic efficiencies toward the oxidative coupling of amines and the iodoperfluoroalkylation of alkenes; higher photocatalytic efficiencies were found for hybrid materials 1 (anion: SiW12O404−) and 2 (anion: SiMo12O404−) compared to 3 (anion: PW12O403−) and 4 (anion: PMo12O403−). The photocatalytic efficiencies of these hybrid materials are mainly controlled by the energy differences between the SOMO‐2 level of Cl4‐PDI⋅−* and the LUMO level of the POMs. The structure‐photocatalytic activity relationships established in present work provide new research directions to both the photocatalysis and hybrid material fields, and will promote the integration of these areas to explore new materials with interesting properties. [ABSTRACT FROM AUTHOR]

Photocatalysis promotes eco-friendly reactions under mild conditions, and among photocatalytic agents are dyes, which have good redox potential in their excited states. The aim of the current contribution was to design a novel series of coumarins based on DFT analysis of their photochemical properties. The coumarin amide group serves as a linking group to cinnamic acid, allowing for electron delocalization throughout the system and the stabilization of the anionic and cationic species. An electronic structure analysis was performed by calculating vertical excitations and emissions, obtaining conceptual DFT chemical descriptors and nonlinear optical parameters (e.g., first static hyperpolarizability β). The novel coumarin derivatives display a reduction in the HOMO–LUMO energy gap from 6.11 to 4.2 eV, large oscillator strength (1.93), efficient nonlinear optical behavior, and excellent redox potential. Hence, they are promising compounds for photocatalytic activity. The present work shows a series of computational parameters that can be considered for the design of a molecule with potential photocatalytic activity, evaluating in this instance a series of new coumarins, promising from the computational point of view [ABSTRACT FROM AUTHOR]

A facile method for the preparation of porous micro/nano fibers was demonstrated. The TiO2/PVDF/CA-composite micro/nano fibers were prepared by centrifugal spinning and then CA was removed by a selective dissolution: reaction with the solution of Acetic Acid. The obtained TiO2/PVDF/CA micro/nano fibers showed highly porous surfaces after the extraction of CA. The structure and properties of PVDF/CA micro/nano fibers were characterized by fourier transform infrared (FTIR), and thermogravimetry (TG), and scanning electron microscope (SEM). The results indicated that CA could be introduced into the PVDF solution and PVDF/CA-composite fibers could be fabricated via centrifugal spinning successfully. CA is dissolved and pores are formed on the fibers. The morphology image of the fibers was detected by scanning electron microscope (SEM) and showed that many pores aligned the nanofibers. The photocatalytic degradation properties of the treated composite fibers were studied. The results showed that the composite fibers prepared by centrifugal spinning had good degradation effects for different concentrations and dyes, and the composite fibers had good reusability. [ABSTRACT FROM AUTHOR]

In this study, Mn-doped ZnO composite carbon nanofibers (Mn-ZnO/CNFs) were prepared via a simple blending and electrospinning (ES) method, followed by a thermal treatment. These fibers were used to investigate the photocatalytic degradation of an organic dye under UV and visible light irradiation. The results showed that Mn-ZnO/CNFs were successfully prepared under the same conditions used for CNFs preparation conditions, which induced a morphological change from a smooth to a rough surface compared to the CNFs. Energy dispersive X-ray (EDX), x-ray diffraction (XRD), and x-ray photoelectron spectroscopy (XPS) analyses confirmed the formation of Mn-doped ZnO on the CNFs' surface. Furthermore, the addition of the catalyst significantly increased in the specific surface area, and a N2 adsorption-desorption isotherm analysis revealed that all samples had mesoporous characteristics with a type IV isotherm index. The photocatalytic activity of the Mn-ZnO/CNFs carbonized at 650 ℃ using methylene blue (MB) dye as a model pollutant was investigated. All prepared samples effectively removed the MB with a degradation rate of 70-90%. The kinetic reaction rate was described using the simplified Langmuir-Hinshelwood equation. Overall, the CNFs and composites nanofibers developed through moderate thermal treatment processes possessed a high specific surface area and oxygen vacancy, enabling their potential use as adsorbents and as a catalyst support for reactions at room-to-elevated temperatures, as well as photocatalysts for the removal of organic contaminants. [ABSTRACT FROM AUTHOR]

Bismuth oxybromide (BiOBr) nanoflowers were anchored onto kaolinite nanosheets via a calcination method. Assisted by characterization methods including XRD, SEM, and XPS, the microstructures of photocatalysts were comparatively investigated. The findings revealed a close integration of BiOBr nanoflowers with kaolinite, resulting in a gradual phase transition and augmented surface oxygen. Furthermore, the photocatalytic performance was assessed by investigating the degradation of organic dyes under visible light irradiation. Notably, the experimental results demonstrated that the degradation efficiencies of BiOBr/kaolinite composites were higher than that of pure BiOBr. The ⋅O2− was proven to be the major active radical in the photocatalytic process. This study presents a straightforward approach for fabricating BiOBr‐based photocatalysts, showcasing their enhanced performance in organic dye degradation under visible light. [ABSTRACT FROM AUTHOR]

Organic dyes in natural waters jeopardize human health. Whether semiconductor materials can effectively degrade dyes has become a challenge for scientific research. Based on this, this study rationally prepared different nanocomposites to remove organic dyes effectively. Pure SnO2 quantum dots, ZnO nanosheets, and SnO2/ZnO (ZS) binary nanocomposites are prepared using the hydrothermal method. Subsequently, SnO2/ZnO@GO (ZSG) ternary composites containing different amounts of GO, i.e., ZSG-5, ZSG-15, and ZSG-25, are synthesized by an ultrasonic water bath method, in which ZS was coupled with GO to form Z-type heterojunctions. The ZSG-15 ternary composites exhibited excellent photocatalytic activity for the degradation of rhodamine B by simulating sunlight. The test results show that the degradation rate of ZSG-15 is about 7.6 times higher than ZnO. The increase in photocatalytic activity is attributed to the synergistic effect of SnO2 and GO to improve the separation efficiency of photogenerated carriers in ZnO. Notably, the large specific surface area of GO increases the reactive sites. Compared with binary nanocomposites, ZSG-15 broadens the response range to light while further accelerating the electron transport rate and improving the photoelectric stability. [ABSTRACT FROM AUTHOR]

Herein we synthesized biochar/iron oxide composite (C/α‐Fe2O3/γ‐Fe2O3) by two‐step calcination method. The prepared C/α‐Fe2O3/γ‐Fe2O3 had a highly pure and a concentration ratio of α‐Fe2O3 and γ‐Fe2O3 about 1 : 1. The optical properties of as‐synthesized C/α‐Fe2O3/γ‐Fe2O3 show a lower bandgap energy (1.90 eV) than that of pure C/α‐Fe2O3 (2.02 eV). The effects of different biochar composite catalysts on the removal of amino black were investigated. Upon illumination, the total removal rate of amino black dye by C/α‐Fe2O3/γ‐Fe2O3 catalyst reached 98 %, which was about 1.7 times that of C/α‐Fe2O3. In addition, the coercivity and the remanence intensity of C/α‐Fe2O3/γ‐Fe2O3 is respectively 1.81 times and 7.17 times that of C/α‐Fe2O3. The catalyst could be magnetically separated and reused for five times with a slight loss of its reactivity. The study of biochar composite provides a new direction for the removal of toxic organic dye in wastewater. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: A photocatalytic [3+2] annulation of alkenes with vinyl azides was developed under irradiation by visible light in the presence of organic dye photocatalysts. Broad substrate scope and high functional group tolerance were demonstrated by more than 50 examples. The reaction provides a novel and efficient method for the synthesis of polyfunctionalized pyrroles under very mild metal‐free conditions without other additives. [ABSTRACT FROM AUTHOR]

This study reports magnetic graphene oxide composite microspheres (MGO) were firstly synthesized via one step miniemulsion polymerization. α-FeOOH rods were then loaded onto MGO via a facile hydrothermal method to prepare α-FeOOH@MGO, which was served as the photocatalyst for the Fenton reaction. Subsequently, the properties of the resulting α-FeOOH@MGO were characterized by FT-IR, XRD, SEM, VSM and UV-vis DRS analysis methods. The influence of various parameters was investigated, such as dye type, dye concentration, H2O2 dosage, catalysts dosage and pH of MO solution during heterogeneous photo-Fenton processes. Under visible light irradiation, the degradation rate of MO, MB and CR could reach 99.96%, 98.47% and 99.97% in 40 min, respectively. Six cycle experiments confirmed that the α-FeOOH@MGO possessed a satisfied stability and recycling ability. In addition, the photocatalytic reaction mechanism was also revealed by the Mott-Schottky plot, band structure and trapping experiments of active species. [ABSTRACT FROM AUTHOR]

Photocatalysis is an innovative method for environmentally friendly wastewater treatment. A development of modern photocatalyst, which is suitable for industrial water purification from hazardous organic compounds, is a global challenging problem. Novelty of this work is in the development of synthetic approach based on hydrothermal treatment in a combination with computational experiment. Oriented attachment mechanism was engaged via hydrothermal treatment to produce SnO2 nanoparticles out of preliminary obtained initial blocks – smaller SnO2 nanoparticles, obtained via precipitation method. The initial blocks and obtained nanoparticles were studied with a large set of methods, such as XRD, FTIR, SSA, HRTEM, XPS, and Raman spectroscopy. The oriented attachment mechanism was studied using a computational method, based on the earlier developed approach, revealing the role of ions, existing in the reaction media, and the path of nanoparticle formation. Initial blocks and obtained nanoparticles were tested as photocatalysts on test solutions of organic dyes (methylene blue, rhodamine 6G and congo red). The more complex the dye structure, the more difficult is photocatalytic decomposition of its molecule. However, optimization of the extraction procedure allowed to achieve up to 90% extraction efficiency. [ABSTRACT FROM AUTHOR]

Currently, textile and food industries produce a significant volume of sewages containing azo dyes and other organic pollutants. These effluents are serious environmental threats, so new methods for their treatment and the degradation of azo dyes are attracting much attention. Composite materials based on TiO2 modified by noble metals and nanoceria show high activity in the photodegradation of organic contaminates and are proposed for hydrogen synthesis as well. To optimize the treatment of contaminants, different processes can combine including the strategies of adsorption, photoluminescence, photocatalysis, etc. The synthesized TiO2-based nanomaterials (sols, powders) will be exploited for bioremediation due to their small size and surface plasmon resonance from noble metals. Binary nanocomposites based on TiO2 were obtained by the chemical co-precipitation method from solutions of titanium tetraisopropoxide (TTIP) and inorganic salts of cerium, silver, and palladium. It has been stated that TiO2 is represented by anatase with primary particle size (CSR) from 8.5 to 16.8 nm, depending on the nature and concentration of the dopant. It is shown that Ag is reduced on the surface of anatase particles and blocks their growth, while Pd and Ce penetrate the titanium dioxide matrix in the form of small clusters with the deformation of the anatase crystal lattice. Nanocomposite particles formed loose and fragile aggregates, which spontaneously dispersed in solutions of dyes with the formation of colloid-stable sols, required the use of a centrifugal field for their sedimentation. Nanoparticles of TiO2&Pd were electronegative and others were electropositive according to the values 4.1÷9.6 of ZPC (zero point of charge). It was shown that the particles of all composites sorbed Methylene Blue (MB) without photocatalytic activity under the visible light to any dye. Moreover, anionic dyes such as OrangeG (Or-G) and Methyl Orange (MO) were excellently discolorated in the presence of TiO2&Pd system; cationic dyes of MB and Rhodamine B (RhB) discolorated too with the TiO2, TiO2&CeO2, and TiO2&Ag systems under UV light action. As such, photocatalysis tests showed that Orange-G’s and MO’s discoloration was higher for TiO2&Pd (2 wt. %) and TiO2 systems with the correlation coefficient R² 0.999. [ABSTRACT FROM AUTHOR]

For a realistic solution, the synthesis of a cost-effective and efficient photocatalyst for the environmental need is utmost essential. Here, a simple in situ hydrothermal method that is a type of “green synthesis” since it doesn’t require harmful chemicals was used to synthesise the simple catalyst Co3O4/reduced graphene oxide/biochar (CBG). The Co3O4 nanoparticles are finely distributed over the sheets of reduced graphene oxide and biochar during the morphological examination, making the composite stable and appropriate for environmental applications. This catalyst was specifically used to create a Z-scheme heterostructure composite that significantly improves the Co3O4 and biochar/rGO photocatalytic performance when exposed to visible light. When it comes to dye and heavy metal Chromium (VI) degradation, the catalyst composite exhibited significantly greater catalytic efficacy compared to individual catalysts. The structural, morphological, and optical features of the CBG nanocomposite were primarily responsible for its exceptional visible light photocatalytic activity with a maximum kinetic rate constant. By optimising the catalyst ratio, the herein described technology can be used to create a promising photocatalyst for environment friendly and sustainable development. [ABSTRACT FROM AUTHOR]

The relevance of the work is related to the solution of environmental problems arising from an increase in the amount of industrial waste water contaminated with organic dyes. The aim of the work was to optimize the process of wastewater treatment from organic dyes - methylene blue, methylviolet and Congo red, when using copper-zinc ferrite, taking into account the change in its mechanism over time and varying the process parameters: the concentration of dye solutions or ferrite mass. Quantitative kinetic characteristics of the process of cleaning solutions from organic dyes with a ferrite composite material of the composition Zn0.875Cu0.1Fe4.42O4 at various mass ratios n = "ferritic composite material: organic dye" are determined. It was proved that the purification of wastewater from organic dyes proceeds through the mechanisms of photocatalytic transformations and sorption and the kinetic characteristics of photocatalytic processes are an order of magnitude higher than those for the adsorption of dyes. An experimental database on wastewater treatment from dyes was created for each mechanism separately. The kinetic equations for the dependence of the concentration of dyes on time and the ratio n are calculated. The cleaning process was optimized for one or two process mechanisms progress while varying the process time, the initial dye concentration or ferrite mass, depending on the need to achieve certain process rates and the depth of cleaning. A scheme of a method for optimizing the process of wastewater treatment from organic dyes using a copper-zinc ferrite composite is proposed. The results are aimed at improving the efficiency and completeness of the purification process. A significant increase in the economic effect of the introduction of the cleaning process is predicted, since it is proposed to use waste from galvanic production for the production of copper-zinc ferrites. [ABSTRACT FROM AUTHOR]

Cobalt aluminate/carbon composite nanoparticles have been synthesised by utilising an auto-combustion method using glycine as an inexpensive fuel. The products were analysed by various techniques such as powder X-ray diffraction (XRD), Fourier transform infrared (FT-IR), thermal analysis (TG), field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS), UV-Vis diffuse reflectance spectrum (DRS), energy-dispersive X-ray spectroscopy (EDS). The results exhibited that the average crystallite size of the as-prepared CoAl2O4/C nanocomposite was ca. 26 nm. The photocatalytic activity of the as-prepared catalyst was evaluated through the degradation of methylene blue (MB) dye under different conditions, and the photocatalytic degradation mechanism was proposed. The results indicated that CoAl2O4/C nanocomposite has a high catalytic performance for the photocatalytic degradation of MB dye under UV illumination in the presence of H2O2. The degradation efficiency reached 98.5% in 90 min with a degradation rate constant of 0.046 min−1. [ABSTRACT FROM AUTHOR]

Photonic crystals (PhCs) are interesting structures for photocatalytic applications because of their capability of harnessing distinct forms of light–matter interactions within the PhCs. Of all these, overlapping one of the photonic stopband's (PSB) edge with the absorption of the PhC material or adsorbed molecules improves their excitation and generated charge carriers can subsequently induce photocatalytic reactions. The PSB position of anodic aluminum oxide PhCs (AAO‐PhCs) can be easily adjusted by modifying the anodization profile. Herein, AAO‐PhCs are designed to match the band gap of a model semiconductor enabling a general photocatalytic activity enhancement independent of the chemical to be decomposed. Fe2O3, as an example photocatalyst, is coated onto AAO‐PhCs to demonstrate efficient photocatalytic systems by utilizing the slow photon effect. Tailored Fe2O3‐AAO‐PhCs with their PSB edge at 564 nm matching the Fe2O3 band gap exhibit generally enhanced degradation of three different organic dyes while a significant activity decrease is observed when the PSB edge does not overlap with the Fe2O3 absorption. Furthermore, photocatalyst degradation can be reduced down to only 4% activity loss over six consecutive measurements by an ultra‐thin alumina coating. [ABSTRACT FROM AUTHOR]

Development of nanocomposites as efficient photocatalysts for the removal of hazardous organic pollutants is always in dire demand due to increase in water pollution. In this article, a facile sol-gel method has been used to synthesize cerium oxide (CeO2) nanoparticles followed by their decoration over multi-walled carbon nanotubes (CNTs) and graphene oxide (GO) to construct binary as well ternary hybrid nanocomposites using ultrasonic treatment. The oxygen vacancy defects have been depicted using X-ray photoelectron spectroscopy (XPS) that may result into improved photocatalytic efficiency. The ternary hybrid nanocomposites (CeO2/CNT/GO) showed excellent photocatalytic efficiency towards degradation of rose bengal (RB) dye up to 96.9% in 50 min. CNTs and GO provide the interfacial charge transfer which inhibits the electron-hole pair recombination. The results obtained here indicate that these composites can be effectively utilized as promising materials for the degradation of harmful organic pollutants for wastewater treatment. [ABSTRACT FROM AUTHOR]

The design of efficient photocatalysts for dye degradation is a challenging task for the scientific community. Semiconductor-based photocatalysts such as g-C3N4 and oxides, utilizing solar energy, have been proven to be effective and promising approaches to resolve this issue to some extent. Constructing Z-scheme heterostructures by coupling g-C3N4 with suitable oxide semiconductors has shown substantial enhancement of the photocatalytic performance. In this article, perovskite-type CeMnO3 (5, 15, 25%) nanoparticle-decorated g-C3N4 nanosheets are fabricated as heterostructures, using a hydrothermal synthesis process, for efficient photocatalysis of organic dyes. The formations of heterostructures are confirmed through structural, microstructural, and elemental state analysis. Brunauer–Emmett–Teller (BET) and Barrett–Joyner–Halenda (BJH) characterization techniques exhibited enhanced surface area and pore sizes, respectively. Ultraviolet–visible (UV–vis) diffuse reflectance spectroscopy (DRS), Mott–Schottky, and linear sweep voltammetry (LSV) analyses along with density functional theory (DFT) calculations predicted a p–n junction heterostructure. Electron paramagnetic resonance (EPR) studies revealed a broad spectrum with sextet hyperfine lines corresponding to Mn4+ and Mn2+ ions and enhanced intensity as compared to the parent ones, signifying the creation of oxygen vacancies in the heterostructure. The CeMnO3 (25 wt %)/g-C3N4 heterostructure showed highly efficient photocatalytic degradation of methylene blue under direct sunlight irradiation, with up to 99% degradation achieved in 120 min and excellent recyclability. The robustness of this photocatalyst was tested by adopting a similar process for methylene orange dye degradation, exhibiting 94% yield in 120 min. A tentative degradation mechanism is proposed based on the enhanced photodegradation efficiency and results obtained from electrochemical impedance (EIS), photoluminescence (PL), LSV, and first principal studies, which provides more insights into the photogenerated charge separation, enhanced photocurrent, and interfacial transfer efficiency through the Z-scheme charge transfer process. This study offers opportunities for designing high-performance Z-scheme hybrid photocatalysts for environmental remediation. [ABSTRACT FROM AUTHOR]

Stress-induced polarization is deemed to be an important avenue for enhancing photocatalytic activity of photocatalysts, which has drawn considerable attention recently. In this report, we have experimentally and theoretically studied the piezoelectricity-enhanced photocatalytic activity and involved mechanism of Bi 2 MoO 6 nanosheets derived via a hydrothermal synthesis route. Simulated sunlight, ultrasonic and both of them were used to drive the photocatalysis, piezocatalysis and piezo-photocatalysis, respectively. It is demonstrated that, for degradation of various organic dyes and antibiotics, the Bi 2 MoO 6 nanosheets manifest a piezo-photocatalytic activity obviously larger than single photocatalytic activity and piezocatalytic activity with synergistic factor SF > 1. The piezoelectricity in the Bi 2 MoO 6 nanosheets and its enhanced photocatalytic mechanism were elucidated through density functional theory (DFT) calculations combined with finite-element method (FEM) simulations. Additionally, taking the typical organic dye — methylene blue (MB) as an example, we have also investigated the effects of various factors on its degradation efficiency, degradation pathways and mechanism, as well as toxic assessment of degradation by-products. [ABSTRACT FROM AUTHOR]

A functionalized gum acacia–activated carbon-CaO/NiO nanocomposite was synthesized using an eco-friendly sol–gel method. The formed nanocomposite was designed to apply various light sources to enhance the improved removal of organic dyes such as methylene blue, methyl orange, methyl red, and rhodamine B from aqueous media. The band gap energies of CaO, NiO nanoparticles and gum acacia–activated carbon were 3.54, 4.28, and 5.34 eV, respectively, corresponding to a reflection edge of 350, 290, and 232 nm, respectively. The surface area of the synthesized nanocomposite was measured to be 17.892 m2 g−1. Sunlight and 20 mg L−1 of the nanocomposite quenched the dyes (methylene blue, 99.7%; methyl orange, 98.3%; methyl red, 96.7%; and rhodamine B, 93.5%) after 120, 100, 100, and 75 min of irradiation, respectively. However, after 80, 100, 100, and 75 min, the percentage of dyes under UV light irradiation was 98.6%, 95.8%, 98.4%, and 94.2% for methylene blue, methyl orange, methyl red, and rhodamine B, respectively. The nanocomposite showed excellent stability after five cycles of dye reduction. [ABSTRACT FROM AUTHOR]

In this work, nanocomposites based on titanium dioxide and reduced graphene oxide (TiO2@rGO) with different weight percentages of rGO (4, 8, and 16 wt%) were prepared by the hydrothermal/solvothermal synthesis method and thermally treated at 300 °C. The prepared nanocomposites were explored for the removal of methylene blue dye (MB) in the presence of simulated solar illumination as well as natural sunlight. The structural, morphological, chemical, and optical properties of the as-synthesized TiO2@rGO nanocomposites were characterized. The obtained results of the graphene-based nanocomposite materials indicated the existence of interactions between TiO2 and rGO, i.e., the Ti–O–C bond, which confirmed the successful integration of both components to form the TiO2@rGO nanocomposites. The addition of rGO increased the specific surface area, decreased the band gap energy, and increased the photocatalytic degradation efficiency of MB from water compared to TiO2 nanoparticles. The results of photocatalytic activity indicated that the amount of rGO in the prepared TiO2@rGO nanocomposites played a significant role in the application of different photocatalytic parameters, including the initial dye concentration, catalyst concentration, water environment, and illumination source. Our studies show that the reinforcement of the nanocomposite with 8 wt% of rGO allowed us to obtain the maximum photocatalytic decomposition performance of MB (10 mg·L−1) with a removal percentage of 99.20 after 2 h. Additionally, the obtained results show that the prepared TiO2@rGO_8 wt% nanocomposite can be used in three consecutive cycles while maintaining photocatalytic activity over 90%. [ABSTRACT FROM AUTHOR]

In this work, cobalt activated TiO2 photocatalyst have been successfully prepared on graphene oxide (GO) using simple and cost‐effective method to prepare Co‐TiO2/GO nanocomposites for the photocatalytic treatment of methylene blue (MB), representative organic dye, under visible light irradiation. The as‐prepared samples were characterized by X‐ray diffraction (XRD), High resolution transmission electron microscope (HRTEM), X‐ray photoelectron spectroscopy (XPS), UV‐vis diffused reflectance spectra (DRS), Raman spectroscopy and photoluminescence spectroscopy (PL). The characterization results confirmed that Co‐TiO2 catalyst is decorated on the graphene oxide. The photocatalytic efficiency of Co‐TiO2/GO for the degradation of MB was also improved by changing the proportion between Co‐TiO2 and GO. Highest photocatalytic activity was observed for Co‐TiO2 loaded with 5 wt % GO (88.7 %) compared with neat Co‐TiO2 (43.4 %) after 180 min of visible light irradiation. Furthermore, degradation by products was analyzed on Quadrupole Time‐of‐Flight Liquid Chromatography/Mass Spectroscopy (QTOF/LCMS) and the possible degradation pathway was proposed. It is investigated that the Co‐TiO2/GO nanocomposite has potential use in the catalytic degradation of organic contaminants under visible light irradiation. [ABSTRACT FROM AUTHOR]

Bismuth MOF catalysts were successfully fabricated using the solvothermal method, which involved the use of a mixed solvent composed of DMF and ethanol in varying volume ratios. Subsequently, the catalysts underwent comprehensive characterization using diverse techniques i.e., FTIR, XRD, N2 adsorption-desorption, UV–vis diffuse, and SEM-EDX. The photocatalytic degradation of RhB was investigated using six different bismuth MOF (BiEt) catalysts. Later, parametric analysis study was performed to test the BiEt catalysts under different values of pH, Rhodamine B (RhB) dye concentrations, and different scavengers. The results showed that BiEt1 had total surface area of 16.78 m2/g and pore volume of 0.025 cm3/g with a pore size of 1.5331 nm. The photocatalytic performance of the catalysts was assessed by quantifying the removal capacity and analyzing theUV–vis absorption spectra during the degradation of RhB. The results show that BiEt 1 had the highest photodegradation efficiency toward the RhB and that it required the shortest time of 60 min to achieve 100% removal. The UV–vis absorption spectra of BiEt catalysts during the degradation of RhB showed that the characteristic absorption wavelength of RhB was observed at 576 nm. These findings suggest that the prepared BiEt was an exceptional photocatalyst for the degradation of RhB. It has great potential for environmental remediation applications. [Display omitted] • Bismuth MOF catalysts revealed exceptional photocatalytic performance, achieving 100% removal of RhB dye within 60 min. • BiEt1 exhibited highest removal capacity of RhB and possessed a total surface area of 16.78 m2/g. • DMF/ethanol solvent mixture improved the photocatalytic efficiency. • The pH significantly influenced the photocatalytic activity of Bi-BTC catalysts. • Scavengers hindered efficiency of RhB degradation. [ABSTRACT FROM AUTHOR]

In summary, the study demonstrates that the photodegradation of methylene blue is influenced by the effective surface charge and colloidal stability of TiO SB 2 sb nanoparticles in aqueous solutions. Designing Highly Active S-g-C 3 N 4 /Te@NiS Ternary Nanocomposites for Antimicrobial Perfo... This research focused on the synthesis of pure nickel sulfide (NiS) nanoparticles, Te-doped NiS nanoparticles (Te@NiS), and nanocomposites combining sulfur-doped g-C SB 3 sb N SB 4 sb (S-g-C SB 3 sb N SB 4 sb ) and Te@NiS through a hydrothermal process. Preparation and Real-World Applications of Titania Composite Materials for Photocatalytic... This article discusses potential applications of the semiconducting transition metal oxide titanium dioxide (TiO SB 2 sb ), which is a cost-effective and non-toxic material known for its excellent photocatalytic properties. Synergistic Correlation in the Colloidal Properties of TiO 2 Nanoparticles and Its Impact... This study explores the relationship between the photodegradation rate of methylene blue (MB) and the effective surface charge of titania nanoparticles (TiO SB 2 sb NPs) in an aqueous solution. [Extracted from the article]

Dye-contaminated water from industry is hazardous to human and aquatic lives. Membrane technology is considered a viable approach to resolve the issue. Herein, copper oxide nanoparticles (CuO NPs) embedded in porous chitosan membranes have been prepared using a solution-casting approach with sodium tripolyphosphate as a crosslinker and polyethylene glycol as a porogen. The prepared membranes have been characterized by physicochemical, mechanical and photocatalytic properties. FTIR results indicate some hydrogen bonding across CuO NPs and the chitosan matrix. XRD and TGA analyses reveal that the membranes are thermally stable and somehow crystalline. SEM examination indicates that the membrane surfaces express porous/roughened texture. The contact angle measurement indicates that the pure chitosan and CuO NPs-embedded membranes are hydrophobic, whereas PEG-leached porous chitosan membranes express hydrophilicity. CuO NPs reinforcement has significantly improved the tensile strength, whereas the elongation at break decreased. The CuO NPs incorporated in chitosan membranes exhibit exceptional photocatalytic activities against methyl orange and methylene blue dyes for their effective removal from aqueous media. [ABSTRACT FROM AUTHOR]

Pollution by organic dyes has received extensive attention due to their high toxicity, biohazard, and high stability in the natural environment, and the development of high‐efficiency dye degradation and heavy metal ion reduction technologies is urgently needed in photocatalysis. However, the interface microenvironment between catalyst and pollutant is often ignored, and the poor compatibility of the catalyst‐pollutant interface constrains further efficient catalysis. Herein, to improve the compatibility of the catalyst‐pollutant interface, a surfactant‐capping strategy for enhanced photocatalysis of rhodamine B (RhB) on one‐dimensional rod‐like Bi2S3 nanocrystals was investigated. Specifically, polyvinylpyrrolidone (PVP)‐capped Bi2S3 (Bi2S3‐PVP) showed enhanced RhB degradation rate compared with pure Bi2S3, and further studies suggested enhanced reaction interface compatibility at the Bi2S3‐PVP‐RhB interface. This work provides an interface microenvironment modulation strategy for improving photocatalytic performance towards organic dyes. [ABSTRACT FROM AUTHOR]

In this study, a Cd-CeO2@C photocatalyst was produced via the calcination of a precursor (Cd-Ce(OH)4@AR14) obtained by co-precipitation of Ce(NO3)3·6H2O, Cd(NO3)2·4H2O and acid red 14 (AR14). The structure, composition, morphology, and optical properties of the synthesized products were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), infrared spectrum (FT-IR), Ultraviolet–Visible Diffuse Reflectance Spectroscopy (UV–Vis DRS), X-ray photoelectron spectroscopy (XPS) and Photoluminescence Spectroscopy (PL). The photocatalytic activity of the synthetized materials was evaluated by performing the degradation of AR14. The results showed that the band gap of CeO2 could be effectively reduced by Cd-doping, and that carbon bonds could decrease the recombination rate of photogenerated electrons and holes, resulting in enhancing the photocatalytic efficiency of the synthesized materials compared with that of pure CeO2. Hydroxyl groups play an important role in the photocatalysis because the adsorption of AR14 over Cd-CeO2@C is greatly affected by the content of hydroxyl groups. Moreover, effect of oxygen vacancies on the photocatalytic efficiency was investigated and the results showed that oxygen vacancies could improve the photocatalytic efficiency of the resulted samples.

This comprehensive and quantitative research offers a thorough analysis of how metal oxides and nanocomposites are used in the photocatalytic treatment of organic dyes. It explores the challenges and opportunities of employing photocatalytic conversion technologies, discussing the optimal conditions for efficient degradation. The mechanisms of photocatalytic degradation are elucidated, highlighting the steps involved in transforming organic dyes into harmless by-products. Additionally, the article examines the factors that enhance the overall efficiency of photocatalytic conversion and compares its cost-effectiveness to other treatment methods. Various photocatalysts, with a focus on metal oxides and nanocomposites, are analyzed in terms of their advantages and limitations in degrading organic dyes. This article serves as a valuable resource for researchers and practitioners seeking sustainable and economical wastewater treatment solutions through efficient and eco-friendly photocatalytic approaches.