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This study aims to elucidate the possible application of cobalt aluminate nanoparticles (CoAl 2 O 4) as a photocatalyst for the removal of organic dyes. The sol-gel method was employed to synthesise Nd x /CoAl 2 O 4 nanoparticles with varying weight percentages (x = 0.0, 0.2, 0.4, and 0.6 wt %). The experimental investigation focused on the photocatalytic destruction of colour, employing a visible light irradiation source. The structural and optical properties of the synthesised nanoparticle were examined through various analytical techniques, including X-Ray Diffraction (XRD), Ultra Violet-Diffuse Reflectance Spectroscopy (UV-DRS), Scanning Electron Microscopy (SEM), Energy-Dispersive X-ray spectroscopy (EDX), Tunnelling Electron Microscopy (TEM), and X-ray Photoelectron Spectroscopy (XPS). The cubic spinel structure was confirmed through the study of the X-ray diffraction (XRD) pattern of the Nd x /CoAl 2 O 4 nanoparticles. For the compositions x = 0.0, 0.2, 0.4, and 0.6, the nanoparticles exhibited average crystallite sizes of 23.73, 22.99, 21.69, and 21.65 nm, respectively. The synthesised nanoparticle exhibited heterogeneous photocatalytic potential when employed as a model pollutant for the oxidative destruction of crystal violet dye. The experimental findings validated that the CoAl 2 O 4 nanoparticle exhibited a dye degradation rate of 64 % during a 100-min timeframe. Additionally, the 0.6 wt % Nd CoAl 2 O 4 nanoparticle shows a quick dye degradation rate of 91 % for crystal violet dyes when exposed to visible light sources. Hence, the synthesised nanoparticle exhibits catalytic activity and holds potential for utilisation in the treatment of hazardous contaminants in industrial wastewater. [ABSTRACT FROM AUTHOR]

Fabrication of efficient perovskite photo-Fenton catalytic systems is recognized as an effective strategy for clean water production. However, modifying perovskite catalysts effectively remains a formidable challenge. In this study, we prepared Bi-doped LaFeO 3 photo-Fenton catalysts using a facile microwave-assisted method. Various characterization techniques confirmed the successful formation of these Bi-doped LaFeO 3 perovskite materials. The photo-Fenton activity of the Bi-doped LaFeO 3 perovskite materials with varying Bi content was assessed by monitoring the degradation of methylene blue (MB) dye solution. Remarkably, the optimized Bi-doped LaFeO 3 (referred to as LBFO3) catalyst achieved approximately 93.64% degradation of MB within 100 min of visible light exposure, demonstrating exceptional efficacy in treating wastewater containing organic dye pollutants. The enhanced photocatalytic activity of the LBFO3 perovskite materials arises from the incorporation of Bi, leading to an expanded optical absorption range, increased specific surface area, and enhanced separation and migration of photo-generated carriers. Importantly, the LBFO3 photo-Fenton system exhibited remarkable stability during four successive cycling treatments, indicating promising practical applications. Additionally, quenching experiments were conducted to elucidate electron transfer in the LBFO3 catalyst related to the photo-Fenton degradation mechanism of MB. This study might pave the way toward designing novel perovskite based photo-Fenton systems for highly efficient degradation of waterborne contaminants. [ABSTRACT FROM AUTHOR]

Over the past few years, organic chemistry has used the organic dye rose bengal's ability to absorb visible light. In present‐day research, the innovation of environmentally friendly processes for carbon‐carbon/carbon‐heteroatoms (Nitrogen, Oxygen, Sulphur, and Phosphorus) bond formation has great importance. The photocatalyzed cross‐dehydrogenative coupling (CDC) reactions using rose bengal (RB) is a promising technique for creating carbon‐carbon/carbon‐heteroatom bonds directly from readily available compounds. Our review focuses on the current advancement in rose bengal that uses photocatalyzed carbon‐carbon/carbon‐heteroatom bond‐making reactions to synthesize various important organic molecules via CDC reactions. [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]

Advance the photo-activity of the nano-sized ZnO photocatalyst is an essential factor in remediation of environmental pollution caused by industrial-organic dyes. Blends of transition elements including Mn, Fe and Co ions were employed to modify the energy gap and the visible absorption state tail of ZnO as well as inhibit the charge carriers recombination by their flexible oxidation states. Five nanocatalysts composed of ZnO, Zn0.97Mn0.015Fe0.015O, Zn0.97Mn0.015Co0.015O, Zn0.97Fe0.015Co0.015O and Zn0.97Mn0.01Fe0.01Co0.01O were simply synthesized. All the prepared compositions have a single phase of ZnO wurtzite structure. Both compositions of Zn0.97Fe0.015Co0.015O and Zn0.97Mn0.01Fe0.01Co0.01O have high sensitive responses to visible light spectrum owing to band gap reduction and formation of absorption state tails. The SEM images demonstrated that the kind of the transition metal blends added to ZnO powder have a significant effect on its morphology. Remarkably, the addition of (Fe, Co) mixture to ZnO powder leads to formation of homogenous rods structure besides very fine spherical particles. All modified ZnO samples revealed enhanced photocatalytic activity but Zn0.97Fe0.015Co0.015O powder possesses the greatest efficiency (98%) for 25 ppm Reactive Yellow 145 dye in 75 min of solar illumination with acceptable stability. In addition, Zn0.97Fe0.015Co0.015O catalyst revealed high photo-removal activity for 25 ppm Rhodamine B and malachite green with measured efficiencies of 94 and 91% in 75 min, respectively. The suitable catalyst dose was identified to be 0.04 g (100 mL solution) and the main effective radicals are the hydroxyl (·OH) species. [ABSTRACT FROM AUTHOR]

In this study, the Mg2+-doped anatase TiO2 phase was synthesized via the solvothermal method by changing the ratio of deionized water and absolute ethanol Vwater/Vethanol). This enhances the bleaching efficiency under visible light. The crystal structure, morphology, and photocatalytic properties of Mg-doped TiO2 were characterized by X-ray diffraction, scanning electron microscopy, high-resolution transmission electron microscopy, N2 adsorption-desorption, UV-Vis spectroscopy analysis, etc. Results showed that the photocatalytic activity of the Mg2+-doped TiO2 sample was effectively improved, and the morphology, specific surface area, and porosity of TiO2 could be controlled by Vwater/Vethanol. Compared with the Mg-undoped TiO2 sample, Mg-doped TiO2 samples have higher photocatalytic properties due to pure anatase phase formation. The Mg-doped TiO2 sample was synthesized at Vwater/Vethanol of 12.5:2.5, which has the highest bleaching rate of 99.5% for the rhodamine B dye during 80 min under visible light. Adding Mg2+-doped TiO2 into the phase-separated glaze is an essential factor for enhancing the self-cleaning capability. The glaze samples fired at 1180 °C achieved a water contact angle of 5.623° at room temperature and had high stain resistance (the blot floats as a whole after meeting the water). [ABSTRACT FROM AUTHOR]

[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]

An efficient eco-friendly photocatalytic method was developed for the synthesis of pharmaceutically highly sought-after quinoxalines. This route is a simple condensation between o-phenylenediamine and an α-hydroxy ketone in methanol at room temperature in the presence of the organic dye Rose Bengal (4,5,6,7-tetrachloro-2',4',5',7'-tetraiodofluorescein) as a photocatalyst. Using this protocol, a library of examples with various ophenylenediamines and α-hydroxy ketones was prepared. This is a practically useful method for the development of quinoxaline derivatives of biological importance in good to excellent yields. [ABSTRACT FROM AUTHOR]

In the current study, CoFe2O4 and TiO2 nanoparticles were primarily made using the sol-gel method, and subsequently, the hybrid magnetic composites of TiO2 loaded with CoFe2O4 (5–15 percent w/w) were made using a hydrothermal procedure. X-ray diffraction (XRD), Fourier transform infrared (FTIR) and Raman spectroscopy, ultraviolet-visible diffuse reflectance spectroscopy (UV-vis DRS), scanning electron microscopy (SEM), and high-resolution transmission electron microscopy (HRTEM) were all used to thoroughly characterize the materials. Additionally, the zero-charge point (ZCP) determination, the examination of the pore structure by nitrogen adsorption, and an evaluation of magnetic properties were performed. Six organic dye pollutants were selected to evaluate the performance of the synthesized nanocomposites toward photocatalytic degradation, including methylene blue (MB), methyl orange (MO), crystal violet (CV), acridine orange (AO), rhodamine B (RhB), and rhodamine 6G (R-6G). Photodegradation of tetracycline (TL), a model pharmaceutical pollutant, was also studied under UV and visible light. The composites exhibited a high degradation performance in all cases without using any oxidants. The photocatalytic degradation of tetracycline revealed that the CoFe2O4/TiO2 (5% w/w) composite exhibited a higher photocatalytic activity than either pure TiO2 or CoFe2O4, and thus attained 75.31% and 50.4% degradation efficiency under UV and visible light, respectively. Trapping experiments were conducted to investigate the photodegradation mechanism, which revealed that holes and super oxide radicals were the most active species in the photodegradation process. Finally, due to the inherent magnetic attributes of the composites, their easy removal from the treated solution via a simple magnet became possible. [ABSTRACT FROM AUTHOR]

Facile preparation route for cobalt tungstate (CoWO 4) via cost effective, time saving, easy and solution combustion approach is described in the present paper. The structural, morphological properties of cobalt tungstate characterized by different physiochemical techniques which include X-ray diffraction, scanning electron microscopy (SEM), energy dispersive X-ray absorption (EDS). The optical properties assessed by UV–visible spectroscopy (DRS) and photoluminescence spectroscopy (PL). Using these methods, it was discovered that CoWO 4 which has been synthesized displayed a monoclinic phase of Wolframite with great crystallinity and purity. The average crystallite size of prepared CoWO 4 was 22 nm and band gap obtained was 2.84 eV due to which it can be used as visible light photocatalyst in aqueous medium. As a result, in this study, the photocatalytic degradation ability of CoWO 4 was assessed by observing the aqueous phase degradation of the most widely used dyes, methylene blue (MB) and Rhodamine-B as well as Cr(VI) reduction under visible light. Almost all MB degraded in 90 min whereas 69 % degradation of RhB takes place in 240 min under visible light irradation. The different aspects for low rate of photodegradation of RhB dye than MB dye was also discussed in this report. The present study deals advanced approach that CoWO 4 can also be used as capable visible light photocatalyst for degradation of dangerous contaminants and for reduction of carcinogenic Cr(VI) into nontoxic Cr(III) from waste water. [ABSTRACT FROM AUTHOR]

CoxZn1−xO system (0 ≤ x ≤ 0.2) was synthesized using the solution combustion method with urea as a fuel source. Photocatalytic tests were performed under visible light to assess the Basic Blue 41 (BB41) conversion. Various characterization techniques, including XRD, FT-IR analysis, SEM, EDS, XRF, BET-surface area, and DRS were used to investigate the composition, structure, and morphology of the synthesized catalysts. In addition, the density functional theory calculation was used in order to study the electronic properties of the ZnO structure. The Box–Behnken model was valid for describing the degradation of BB41 dye according to the analysis of variances results. A maximum conversion of 100% for BB41 dye has been reached with high mineralization and important removal of chemical oxygen demand. The optimum conditions for BB41 conversion are reported. On the other hand, the reuse tests of the best catalyst showed high-performance stability after five cycles. Furthermore, the activity of superoxide ions (O2·−) and hydroxyl radicals (OH.) as the spices responsible for BB41 dye conversion was well confirmed by the free radicals scavenging tests. The use of Box–Behnken optimization and DFT calculation applied to the synthesized catalysts proves to be a very suitable procedure to establish the operating conditions under which the synthesis strategy of the CoxZn1−xO catalyst in its activity in the visible region performs an excellent efficiency for the degradation of organic dyes and makes contributions to the current literature related to the field of environmental technology. [ABSTRACT FROM AUTHOR]

Herein, novel visible light active graphitic carbon nitride (g-C3N4)/sepiolite fiber (CN/SS) composites were fabricated via a facile calcination route, exploiting melamine and thiourea as precursors, and sepiolite fiber as support, for efficient degradation of organic dye methylene blue (MB). The as-prepared CN/SS composites were characterized by various characterization techniques based on structural and microstructural analyses. The effects of CN loading amount, catalyst dosage and initial concentration of dye on the removal rate of dye under visible light were systematically studied. The removal rate of MB was as high as 99.5%, 99.6% and 99.6% over the composites when the CN loading amount, catalyst dosage and initial concentration of dye were 20% (mass percent), 0.1 g, and 15 mg/L in 120 min, respectively. The active species scavenging experiments and electron paramagnetic resonance (EPR) measurement indicated that the holes (h+), hydroxyl radical (·OH) and superoxide radicals (·O2−) were the main active species. This study provides for the design of low-cost, environmentally friendly and highly efficient catalysts for the removal of organic dye. [ABSTRACT FROM AUTHOR]

Ni-doped γ-Bi 2 O 3 was successfully synthesized via a one-pot oil bath synthesis. The prepared materials were characterized by XRD, DLS, SEM, FT-IR, EDS, TEM, and XPS. The XRD patterns confirmed the pure phase formation of tetrahedral γ-Bi 2 O 3. The material was tested for the degradation of various organic dyes and exhibited outstanding efficiency and selectivity for the photodeterioration of Congo red compared to other organic dyes. Furthermore, different Ni percentages were doped to find the best possible photocatalyst for Congo red degradation, with the 2 % Ni-doped γ-Bi 2 O 3 exhibiting an improved performance. The photocatalytic degradation efficiency of Congo red reached 93 % after 80 min and was used for three consecutive cycles without a considerable decrease in activity. UV–visible DRS spectra and the Mott-Schottky plot were used to understand the energy diagram of the materials. The higher visible light absorption and charge separation efficacy of the photogenerated electron-hole pairs induced by Ni loading contributed to improved photocatalytic performance. This study introduces a novel method for synthesizing Ni-doped tetrahedral γ-Bi 2 O 3 microstructures with precisely controlled morphology for the selective degradation of Congo red dye. [Display omitted] • Ni-doped γ-Bi 2 O 3 was synthesized via a novel facile one-pot oil bath synthesis. • This is the first photocatalysis work using the Ni-doped γ-Bi 2 O 3 phase. • The material exhibited outstanding selectivity for the degradation of Congo red. • The efficacy of Congo red reached 93 % after 80 min with 2 % Ni-doped γ-Bi 2 O 3. [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]

In order to improve the treatment efficiency of printing and dyeing wastewater, the carbon nanotubes-silver-modified-titanium dioxide (CNTs-Ag-TiO2, CAT) ternary composite was prepared by a mechanical mixing method. It was found that the morphology of the prepared CAT sample was uniformly coated with strips of CNTs, speckled Ag, and lumpy TiO2. The (002) crystal plane of CNTs, the (101) crystal plane of TiO2, and the (111) crystal plane of Ag were observed, which possessed functional groups such as Ti-OH and Ti-O-C, indicating that the prepared CAT sample had photocatalytic reaction sites. The visible light utilization of titanium dioxide can be improved. The treatment effect of different proportions of CNTs-Ag-TiO2 on Congo red wastewater was tested, and the results showed that the optimum degradation effect of Congo red wastewater was CNTs: Ag = 10:1, and the doped amount of CNTs/Ag was 15%, and the removal rate of Congo red wastewater could reach 100% within 140 min. The excellent removal effect of CAT ternary composite on Congo red wastewater provided a new idea and way for the modification of TiO2 and its composites for the potential of organic dyes degradation. [ABSTRACT FROM AUTHOR]

According to the literature, Co2+ ions effectively tune the electronic and optical properties of ZnO in photocatalytic applications. Herein, an excellent degradation efficiency of 99.7% for Direct Blue 71 (DB71) under visible light excitation is obtained using the high-purity Co2+-doped ZnO nanoparticles synthesized by a facile hydrothermal method. The highest removal value is received at the level of the Co2+ ion of 3 mol%, the catalyst mass of 0.1 g, the initial DB71 concentration of 100 mg/L, and the pH value of 6. It is demonstrated that Co2+ could substitute for Zn2+ ions in the ZnO lattice at the low concentration (≤ 3 mol%) and locate the interstitial sites of Zn at the higher dopant level (≥ 5 mol%). The decrease in the optical-absorption edge with an increment in dopant level (1–7 mol%) could be attributed to charge carrier concentration and particles size. It is speculated that the degradation mechanism of DB71 is mainly based on the interaction between hydroxyl radicals ( ∙ OH ) and organic dye. [ABSTRACT FROM AUTHOR]

A series of binary composite photo‐catalyst BiOBr/MgBTC (the ligand of MgBTC is 1, 3, 5‐benzenetricarboxylate = H3BTC) with different content of BiOBr have been designed and used to degrade the traditional dye rhodamine B (RhB). As‐prepared binary composites have been first obtained via a simple hydrothermal system and subsequently deposited onto the BiOBr substrates. The composites exhibited better catalytic performance compared with the pristine BiOBr, and the performance of BM‐55 (synthesized by 0.55 mmol BiOBr and 0.45 mmol MgCl2•6H2O) was the most efficient and its removal rate of RhB can reach 98.3% within 60 min. The composite photo catalyst was characterized by X‐ray diffraction (XRD), infrared (IR), scanning electron microscope (SEM), X‐ray photoelectron spectroscopy (XPS), diffuse reflectance spectroscopy (DRS), photoluminescence (PL), and electrochemical impedance spectroscopy (EIS), respectively. In the free radical trapping experiments, it can be seen that the main photo‐catalytic active species are superoxide radicals (•O2−) and holes (h+). This work can provide considerable opportunities to the development of various metal–organic frameworks (MOF)‐based visible light photo‐catalysts and modified 2D bismuth ox halide materials (BiOX) for use in environmental cleaning application. [ABSTRACT FROM AUTHOR]

In this study, hierarchical bismuth oxyhalide BiOI0.5Cl0.5 was successfully synthesized and adopted for the adsorption and vis-photocatalytic removal of aquatic dyes. The morphology and physiochemical properties of BiOI0.5Cl0.5 were investigated by Fourier-transform infrared spectroscopy, UV-visible, diffuse reflectance spectroscopy, scanning electron microscopy, transmission electron microscopy, X-ray diffraction, Brunauer-Emmett-Teller. Three metachromatic dyes, Rhodamine B (RhB), Methylene blue (MB), and Congo red (CR)were selected as targets due to their photosensitivity. Several crucial factors concerning temperature, pH, material dosages, and scavengers were elucidated. The as-prepared BiOI0.5Cl0.5 exhibited sound adsorption capability for the three dyes, with the removal rate reaching 90.0%, 79.0%, and 83.2% for RhB, MB, and CR, respectively, after 120 min reaction, which could be well-fitted by the pseudo-second-order kinetics and the Langmuir model. Due to the promising performance of BiOI0.5Cl0.5, the removal of selected dyes was significantly enhanced under visible light irradiation. While the adsorption capacity of RhB and MB was decreased by 17.39% and 18.99%, respectively, the differential removal behaviors were observed in photocatalysis over the pH range of 2.0-10.0. The Langmuir-Hinshelwood (L-H) model for photochemical systems was established and verified for various conditions. Through scavenger study, the major reactive species for the degradation of the selected dyes using BiOI0.5Cl0.5 under visible light are h+ and •O2- instead of •OH. This study provides potential insight into the removal of aquatic dyes using simultaneous adsorption and photochemical treatment under solar light. [ABSTRACT FROM AUTHOR]

Photocatalysis technology has risen to effectively degrade the hardly-degraded organic pollutants in recent years and the photocatalysts play an important role in striding the obstacles of the visible light response. Herein, a high-efficiency BiVO4/Bi5O7I heterojunctional photocatalysts have been purposefully designed by controlling the reactant ratios and ultrasonic time of reaction at room temperature. Photocatalytic experimentals confirm that the prepared optimal BiVO4/Bi5O7I composites displayed enhanced photocatalytic ability to degrade rhodamine B and quinoline blue under visible light irradiation. Furthermore, the photocatalysts exhibits high photostability and reusability proved by four consecutive cycling experiments. A possible mechanism of p–n heterojunctional BiVO4/Bi5O7I composites enhanced the photocatalytic performance was discussed in detail on the basis of the reactive species trapping experiments in photocatalytic degradation process. [ABSTRACT FROM AUTHOR]

• Uniform and smooth Cu(0)-loaded polymeric fibers were prepared by one-step electrospinning. • Microwave Ar plasma treatments allowed to generate Cu/Cu 2 O nanostructures on fibers. • Various morphologies of Cu/Cu 2 O nanostructures were modulated by plasma treatments. • The plasma treated fibers displayed the highest photocatalytic activity toward methyl orange and 4-NP under visible light. Self-standing photocatalytic materials based on transition-metal decorated electrospun fiber mat have attracted considerable attention for photodegradation of toxic refractory organic pollutants in the environment. In this study, poly(N-vinylpyrrolidone)/copper(II) nitrate fibers (Cu/PVP-F) were prepared by electrospinning of PVP/Cu(NO 3) 2 solution followed by crosslinking using microwave-induced argon plasma (MAP) to produce Cu/Cu 2 O composites on the surface of fibers. The optimization for the electrospinning fibers was conducted such that the optimized electrospun composite fibers exhibited excellent visible light photocatalytic activity, corresponding to the narrowest band gap energy based on photoluminescence analyses. Moreover, the experimental results showed that the electro-spinning Cu/PVP-F fibers treated with MAP revealed the highest rate of photodegradation efficacy toward methyl orange (MO) and 4-nitrophenol (4- NP), that could be employed in the subsequent photocatalysis cycles with good recovery. [ABSTRACT FROM AUTHOR]

• Ni co-doped Al-ZnO photocatalyst was synthesized by high energy ball-milling method. • XRD, EDX and XPS measurements confirm the existence of Al and Ni in ZnO sites. • The photocatalytic activity of (Al, Ni) co-doped ZnO was evaluated by studying the degradation of MO and CR dyes. • A2 (2%Al, 2%Ni) co-doped ZnO was shown the highest catalyst activity amongst the series of ZnO. • Trapping experiments confirmed that the O2 were responsible for degradation of dyes. (Al, Ni) co-doped ZnO nanostructures were synthesized by a simple ball-milling method. The samples prepared were extensively characterized using standard techniques. X-ray diffraction analysis confirmed the coexistence of Al and Ni in the ZnO sites. The pollutant photodegradation performances of the materials were assessed by studying the removal of methyl orange and Congo red under visible-light illumination. Of the photocatalysts prepared, 2%Al-2%Ni-ZnO was found to be the most active for pollutant degradation, effecting 100% removal of MO within 30 min under visible-light illumination. This excellent catalytic activity was attributed to the strong absorption of visible light and effective separation of photoinduced charge carriers. In addition, radical-scavenging experiments were conducted to identify the key reactive species formed in the reaction, allowing a mechanistic rationale for the superior photocatalytic activity of 2%Al-2%Ni-ZnO to be proposed. [ABSTRACT FROM AUTHOR]

Herein, a visible‐light photochemical approach for practical helicene functionalization at very mild reaction conditions is described. The photochemical reactions allow for the regiospecific and innate late‐stage functionalization of helicenes and are easily executed either through the activation of C(sp2)−Br bonds in helicenes using K2CO3 as inorganic base or direct C(sp2)−H helicene bond functionalization under oxidative photoredox reaction conditions. Overall, using these transformations six different functional groups are introduced to the helicene scaffold through C−C and four different C‐heteroatom bond‐forming reactions. [ABSTRACT FROM AUTHOR]

• The novel ternary Fe 2 O 3 /MoO 3 /AgBr photocatalyst was fabricated. • The heterostructure exhibited the best photocatalytic activity under visible light. • Effect of different experimental conditions were examined in organic dye degradation. • Photocatalytic mechanism was proposed, and confirmed by using various scavengers. In the present work, the novel ternary Fe 2 O 3 /MoO 3 /AgBr photocatalyst with different dosages of AgBr was successfully synthesized via a facile method. The physicochemical properties of the resultant catalyst were characterized by using various techniques such as XRD, SEM, EDX, BET, XPS, DRS, and VSM. The photocatalytic performance of as-prepared samples was evaluated by degradation of organic dye acid blue 92 (AB92) under visible light irradiation, and in dark. The impact of different operating parameters namely calcination temperature, amount of photocatalyst, dye concentration, and pH of solution were investigated in degradation reaction. Ternary nanocomposite exhibited the best photocatalytic activity due to synergistic effect between nanostructures, high visible light adsorption, and effective separation of charge carriers. The photocatalytic activity of this nanocomposite is about 7.1, and 5.1-fold higher than those of the Fe 2 O 3 , and Fe 2 O 3 /MoO 3 , respectively. The results displayed that the superoxide radical (O 2 · - ), and photo-generated hole ( h +) play the major role in the dye decomposition under visible light. The photocatalyst was easily separated from the reaction media by an external magnet, and used in five consecutive cycles without losing the activity, and stability. [ABSTRACT FROM AUTHOR]

• Prepared composite nanofiber membrane possesses a good photocatalyst performance. • High degradation activity of organic dyes under visible light. • The composite nanofibers membrane possessed excellent recovery and reuse. • The free-standing membrane is flexible and easy to handle. • The flexibility of the composite nanofibers allows use in a continuous operation. This study proposed an effective method by using photocatalytic composite nanofiber membranes in order to degrade malachite green (MG) and acid red 27 (AR 27) to harmless products. The photocatalytic composite nanofiber membrane, Polyacrylonitrile (PAN) was incorporated with catalyst SiO 2 and TiO 2 photocatalyst. The PAN/SiO 2 -TiO 2 -NH 2 nanofiber membrane was synthesized by electrospinning technique followed by chemical crosslinking. The results of SEM, EDX, FTIR and XRD confirmed the successful preparation of nanofiber membrane. XRD analysis shows the confirmation of SiO 2 and TiO 2 peaks. The result shows that PAN/SiO 2 -TiO 2 -NH 2 nanofiber membrane exhibit the highest degradation with a good distribution of SiO 2 and TiO 2 on the PAN nanofiber membrane surface. The results showed that the complete photodegradation of MG and AR 27 with artificial visible-light was achieved after 9 and 25 min, respectively. In addition, the nanofiber membrane exhibited good stability and reusability for MG and AR 27 photodegradation and has potential to be applied in industrial application. [ABSTRACT FROM AUTHOR]

Three novel chemically stable porous organic polymers (POPs) were synthesized by the hydrothermal method; the POPs contain sulfone bonds (TpSD), no sulfur atoms (TpMD), or thioether bonds (TpTD). The catalytic mechanism of the POP with sulfone bonds was studied, and it was found that the wide visible light absorption range, high specific surface area, and the hydrophilicity of the material significantly promoted the catalytic efficiency of TpSD. The presence of O=S=O gives TpSD a higher degree of conjugation than TpMD and TpTD, so TpSD shows the strongest UV/Visible absorption and faster transmission of electrons. The photocatalytic degradation of Rhodamine B (RhB) molecules is approximately 100 % with TpSD and its pseudo‐first‐order rate constant is 0.0770 min−1, which is the highest among all reported non‐metallic photocatalysts. Moreover, it is also the first time that sulfur‐containing polymer have been used in photocatalytic degradation of dyes. [ABSTRACT FROM AUTHOR]

Visible-light-driven organic photochemical reactions have attracted substantial attention from the synthetic community. Typically, catalytic quantities of photosensitizers, such as transition metal complexes, organic dyes, or inorganic semiconductors, are necessary to absorb visible light and trigger subsequent organic transformations. Recently, in contrast to these photocatalytic processes, a variety of photocatalyst-free organic photochemical transformations have been exploited for the efficient formation of carbon–carbon and carbon–heteroatom bonds. In addition to not requiring additional photocatalysts, they employ low-energy visible light irradiation, have mild reaction conditions, and enable broad substrate diversity and functional group tolerance. This review will focus on a summary of representative work in this field in terms of different photoexcitation modes. 1 Introduction 2 Visible Light Photoexcitation of a Single Substrate 3 Visible Light Photoexcitation of Reaction Intermediates 4 Visible Light Photoexcitation of EDA Complexes between Substrates 5 Visible Light Photoexcitation of EDA Complexes between Substrates and Reaction Intermediates 6 Visible Light Photoexcitation of Products 7 Conclusion and Outlook [ABSTRACT FROM AUTHOR]

• A mild and efficient one-pot visible light-induced method. • Metal-free organic dyes have been used. • Functionalization of a wide range of native C H bonds in an economical and sustainable manner. A visible light promoted, photoredox catalysed, green one-pot approach for the alkylation of amine substrates with sp2 carbon has been developed. This eosin Y based organic transformations, can behave as an effective direct hydrogen-atom transfer catalyst for coupling reaction. The proposed strategy includes simple procedure which can make adduct product with sp2 carbon. This eosin Y based photocatalytic hydrogen-atom transfer strategy may hold great potential for diverse functionalization of a wide range of native C H bonds in an economical and sustainable manner. [ABSTRACT FROM AUTHOR]

Abstract SnS 2 exhibits lower photocatalytic activity against organic dyes without N N double bonds due to the SnIV/SnII transition which decreases its degradation efficiency due to the decreased formation of O 2 ∗ − and OH∗ radicals. To upgrade the photocatalytic ability of SnS 2 against dyes without N N bonds, NiO coupling has been adopted and the results obtained are furnished in this paper. By adopting precipitation method, SnS 2 , NiO and SnS 2 NiO nanocomposite was synthesized. Structural, morphological, compositional, functional group analyses of SnS 2 , NiO and SnS 2 NiO nanocomposite were performed by adopting techniques such as XRD, SEM, TEM, XPS, FTIR and PL. The magnetic property of pure SnS 2 got enhanced by coupling with NiO thereby making it suited for magnetic devices. Photocatalytic activities were performed against MB and RhB dyes under visible light. The enhanced degradation ability of the SnS 2 NiO composite may be due to its enhanced oxidation/reduction ability of the electrons and holes generated under the effect of visible light. Highlights • Precipitation method is used to synthesize SnS 2 NiO composite. • Magnetic property of pure SnS 2 is enhanced when coupled with NiO. • The photocatalytic activity of pure SnS 2 got enhanced by forming composite with NiO. • The SnS 2 NiO composite degraded MB better than RhB dye. [ABSTRACT FROM AUTHOR]

In recent years, visible‐light‐induced C−H bond functionalization has become an emerging field at the forefront of organic chemistry. In a general sense, these approaches rely on the capability of metal complexes and organic dyes to convert visible light into chemical energy by engaging in single‐electron transfer with organic substrates, thus generating reactive intermediates. This review covers most of the strategies involving visible light‐induced benzylic and non‐benzylic alkylation, halogination, oxidation, vinylation, arylation, benzylation, acetylation, formylation, thiocyanation, xanthylation, azidation, amination, addition, and coupling reactions of sp2 and sp3 C−H bonds. [ABSTRACT FROM AUTHOR]

Fe 3 O 4 /Pr-BiOCl/Luffa (FPBL) composites were successfully prepared for the first time via a two-step synthesis method. The composites were characterized by a number of techniques including XRD, FTIR, SEM, DRS, BET, XPS, PL, UV–vis and VSM. The photocatalytic activity of FPBL was further evaluated through the photodegradation efficiency of Rhodamine B (RhB). Almost all RhB was removed after 120 min visible light irradiation in the present of the FPBL. The effects of dose and pH were also studied, and the best performance was achieved at pH 6 while the dose of as-prepared photocatalyst was 1.0 g/L. The as-prepared photocatalyst can be magnetically recycled, and it maintained high photocatalytic activity after six-cycle of photodegradation. The free radical trapping experiments demonstrated that the holes (h + ) and electrons (e − ) were two main active species in the photocatalytic degradation of RhB. This work suggests the Fe 3 O 4 /Pr-BiOCl/Luffa composites are promising photocatalysts for organic pollutant degradation. [ABSTRACT FROM AUTHOR]

An organic dye photoredox‐catalyzed regiospecific radical cascade annulation strategy of 2‐alkynyl‐azidoarenes to generate 3‐sulfenylindoles via vicinal thioamination of alkynes at room temperature, mediated by visible light, was developed. The method requires mild conditions, including visible light as a traceless green energy source, room temperature, eosin Y organic dye as a photoredox catalyst, ambient air as oxidant, and easily available starting materials to provide a green, efficient, metal‐ and strong‐oxidant‐free synthesis of 3‐sulfenylindoles with broad substrate scope through vicinal thioamination of alkynes. [ABSTRACT FROM AUTHOR]

Design and usage of efficient visible light photocatalytic systems for wastewater treatment and degradation of organic dyes are of remarkable interest in the fields of environmental protection. In this study, magnetic ZnFe 2 O 4 , ZnFe 2 O 4 /ZnO, Tannin/ZnFe 2 O 4 and Tannin/ZnFe 2 O 4 /ZnO nanocomposites with interfacial contact have been synthesized. The photocatalytic efficiencies of as-obtained samples are analyzed by the degradation of indigo carmine in aqueous solution under UV and visible-light. The degradation ratios of IC are 82% and 99% of IC over the Tannin/ZnFe 2 O 4 /ZnO under the both of UV light and visible light for 90 min, respectively. And after five times recycling, the photocatalytic performance of IC presence the Tannin/ZnFe 2 O 4 /ZnO can even reach nearly 89.79%. The results demonstrate that the Tannin/ZnFe 2 O 4 /ZnO exhibits great photocatalytic efficiency for indigo carmine (IC) compared to their constituent photocatalysts and easy separation from dye solution by magnet. The synergistic interactions between ZnFe 2 O 4 , tannin and ZnO prolonged lifetime of photoexcited carriers leading to greater absorption in both UV and visible light. This nanocomposite was beneficial for separating the photogenerated charge carriers and facilitating electron transfer. Tannin has a decisive role for increasing the photocatalytic performance of ZnFe 2 O 4 due to the abundant units of phenolic groups in tannin molecules. ZnFe 2 O 4 makes the Tannin/ZnFe 2 O 4 /ZnO magnetically separable in a system. This work presents new insights that tannin molecules function as great modifier to improve very impactful tannin-modified magnetic photocatalysts in removing environmental contamination. [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]

Pseudohalides are well known to do similar chemistry like halides. Thiocyanate, a pseudohalide acts like halides in many ways. Thiocyanate radicals ( SCN) are generated from readily available thiocyanate salts using Rose Bengal through single electron transfer (SET) in the presence of visible light. Thiocyanate radicals abstract hydrogen like other halide radicals, so this aspect of chemistry was used for the oxidation of alcohols to their corresponding aldehydes using oxygen as the terminal oxidant. This method shows a broad scope and well tolerance towards various functional groups. [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]

Methylene blue catalyzes the visible light-induced organocatalytic α-oxyamination of aldehydes via enamines. The irradiation of 3-phenylpropanal with TEMPO radical in the presence of morpholine as an organocatalyst and methylene blue as a photoredox catalyst gave the desired a-functionalized aldehyde in 75% yield. [ABSTRACT FROM AUTHOR]

In this study, the zinc oxide-decorated graphitic carbon nitride composite (ZnO/gC 3 N 4 – ZCN) was synthesized for photocatalytic degradation of organic dyes in aqueous media. Particularly, ZnO was fabricated by the calcination method with the assistance of Garcinia mangostana pericarp extract as a stabilizer and reducing agent, while graphitic carbon nitride (gC 3 N 4 – CN) was prepared by the calcination method and exfoliated using a strong oxidizer mixture. Characterization results showed ZnO possesses a spherical shape with an average diameter of 30–80 nm and is distributed evenly on the CN sheets. Subsequently, ZCN was subjected to photodegradation towards methylene blue (MB), which indicated that under optimal conditions of 50 mg of catalyst, pH 9, and 10 mg/L of MB concentration, the overall efficiency reached up to 99.16 % after 180 min of visible irradiation. Additionally, ZCN also possesses the degradation ability for other organic dyes, for instance, malachite green (MG) and methyl orange (MO) with an overall efficiency of 96.42 and 57.57 %, respectively. Moreover, the radical scavenging experiments elucidated that the major responsible component for the photodegradation was the photogenerated holes, while other radicals also facilitated the process. Besides, the reusability of the material was excellent as only 10 % of the yield decreased after five cycles. The aforementioned findings reveal the notable potential applications of the ZCN material in the environmental remedial field. [Display omitted] • The ZnO/gC 3 N 4 composite was biosynthesized with the aid of sonication. • The spherical ZnO distributed evenly on the gC 3 N 4 exfoliation sheet. • The composite exhibited great methylene blue photodegradation under visible light. [ABSTRACT FROM AUTHOR]

Novel hierarchical Fe 3 O 4 @MoS 2 /Ag 3 PO 4 magnetic nanophotocatalyst with remarkable photocatalytic capability were prepared by simply depositing the Ag 3 PO 4 onto the surface of crumpled Fe 3 O 4 @MoS 2 nanosphere. The nanocomposites were characterized by XRD, TEM, HRTEM, XPS, BET, and UV–vis DRS. The outcome of the photocatalytic experiments demonstrated that Fe 3 O 4 @MoS 2 /Ag 3 PO 4 with 6 wt% content of Ag 3 PO 4 (FM/A-6%) showed the highest photocatalytic activity upon the degradation Congo red (CR) and Rhodamine B (RhB) under both visible light and simulated sunlight irradiation. In addition, FM/A-6% possessed larger specific surface area (76.56 m 2 /g) and excellent optical property. The possible Z-scheme charge carriers transfer mechanism for the enhanced photocatalytic properties of the FM/A-6% was also discussed. The Z-scheme charge carriers transfer mechanism established between MoS 2 and Ag 3 PO 4 facilitate the charge separation efficiency. Moreover, FM/A-6% can be separated and collected easily by external magnetic field and maintain high activity after five times photoreaction cycles. Given the remarkable photocatalytic performance and high stability of FM/A-6% nanocomposite, it is looking forward to exhibit great potential for applications in water purification. [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]

• Polyethersulfone membrane was fabricated based on Sb 2 O 3 /CuBi 2 O 4 nanocomposite. • Photocatalytic efficiency of dyes under visible light irradiation was evaluated. • The Sb2O3/ CuBi 2 O 4 photocatalyst has a good efficiency in visible light. • Integration of photocatalyst with membrane was improved dye degradation efficiency. Methylene blue (MB) and Acid Blue 25 (AB 25) dyes are organic substances that are potentially harmful to humans and the environment. In this study, a photocatalytic membrane was fabricated based on Sb 2 O 3 /CuBi 2 O 4 (Sb 2 O 3 /CBO) composite for the degradation of MB and AB 25 dyes under visible light irradiation. At the first, several significant parameters such as pH (2, 5, 7, 9, and 11), initial dye concentration (10, 30, 50, 60, and 75 ppm), and photocatalyst dosage (0.005, 0.0075, 0.01, and 0.02 g) were optimized by using Sb 2 O 3 /CBO composite under visible illumination in a batch system. Moreover, various characteristics of the as-synthesized materials were analyzed by FESEM, FTIR, XRD, PL, and UV–Vis DRS. Additionally, the continuous experiments were conducted with a hybrid of several percentages of produced nanoparticles and Polyethersulfone membrane to maximize the process efficiency. Results show that an increase in pH and catalyst dosage had a positive influence on dye degradation. Furthermore, the photocatalytic decolorization of MB in an alkaline solution was higher than that of the acidic solution and vice versa for AB 25. The optimum initial concentration and photocatalyst dose for both dye solutions were determined to be 10 ppm and 0.01 g, respectively, whereas the optimal pH values for AB 25 and MB were 2 and 11. The highest photocatalytic dye removal efficiency (94.6 percent) was obtained under optimal conditions using a 10% Sb 2 O 3 /CBO photocatalyst in the presence of a membrane. [Display omitted] [ABSTRACT FROM AUTHOR]

Dyes can CO do it: Organic dyes and pigments are usually applied in textile dyeing, which can be dated back to the Neolithic period. Interestingly, the possibility to use organic dyes as photoredox catalysts has also been noticed by organic chemists and applied in organic synthesis. Carbonylation reactions as a powerful procedure in carbonyl‐containing compound preparation have also been studied. In this manuscript, the recent achievements in using organic dyes as visible‐light sensitizers in carbonylation chemistry are summarized and discussed. [ABSTRACT FROM AUTHOR]

Selective functionalization of C(sp 3 ) H bonds is one of the final frontiers of synthetic chemistry. The employment of organic dyes (ODs) as visible light photocatalysts to approach these reactions has been of current interest mainly due to their lower cost and the avoidance of toxic heavy metals. In this digest, we outline the recent advances in organic dye-catalyzed C(sp 3 ) H functionalization reactions. [ABSTRACT FROM AUTHOR]

The commercially available TiO 2 Degussa P25 was modified using a simple technique to produce a visible-light-actived indium and carbon doped P25 catalyst. The modified photocatalysts have been successfully obtained by thermal heating method. These as-obtained products were successfully characterized by X-ray diffraction (XRD), X-ray photoelectrion spectroscopy (XPS), scanning electron microscope (SEM), high resolution transmission electron microscopy (HRTEM), UV–vis diffuse reflectance spectroscopy (DRS) and photoluminescence (PL) spectroscopy respectively. The photocatalytic activities of all prepared catalysts were evaluated by the degradation of organic dyes including methylene blue (MB) and Reactive Red 4 (RR4) under visible light irradiation. As the result shown, the indium and carbon co-doped on P25 nanocomposites possessed the extended light absorption in visible light and better charge separation capability as compared to the pristine P25. The optimum loading of In 3+ ions on P25 was 15%. Moreover, 15% In 2 O 3 /C-P25 showed the highest degradation rate of organic dye, which the removal efficiency can reach over 90% after 90 min and the corresponding hydrogen evolution rate of 15% In 2 O 3 /C-P25 was 9 times than P25. It was concluded that the synergistic effects of In 3+ ions and carbon narrowed the band gap of TiO 2 and promoted charge separation, which played a significant role for the enhancement of photoactivity. In addition, it was observed that the photo-degradation for all catalysts followed the first order reaction kinetics. Furthermore, the influence of initial pH values on the photocatalytic degradation of MB and RR4 using 15% In 2 O 3 /C-P25 catalyst was also investigated. Finally, the stability test of photocatalysts was carried out and the photocatalytic mechanism was explained concretely. [ABSTRACT FROM AUTHOR]

Electrospun cellulose acetate (CA) membrane was employed as a support that provided sites for AgCl crystals in situ growth. The Ag@AgCl crystals on electrospun CA composites with exposed {1 0 0} and {1 1 1} facets were fabricated at room temperature by a double diffusion technique. The crystal structure, morphology, composition, and absorption light ability of CA supported Ag@AgCl were characterized utilizing X-ray powder diffraction (XRD), scanning electron microscopy (SEM), attenuated total reflection-infrared intensity (ATR-IR), X-ray photoelectron spectroscopy measurements (XPS), energy dispersive spectrometer (EDS) and ultraviolet–visible (UV–vis) diffuse reflectance spectra, respectively. The photocatalytic activity of the catalysts was evaluated using methyl orange (MO) as a target. The CA supported cubic Ag@AgCl catalyst exhibited much higher catalytic activity than octahedral catalyst in terms of the degradation of MO under visible light. The 10 mg CA based cubes could completely degrade MO (10 mg L −1 ) in 160 min. The photocatalyst still exhibited a good catalytic ability after three times. [ABSTRACT FROM AUTHOR]

[Display omitted] • Construction of sustainable type-II Fe 3 O 4 @SiO 2 @ZnO-CuS heterojunction via simple chemical route. • Synergism of CuS nanoplates and magnetic ZnO in visible light mediated degradation process. • Magnetic ZnO-CuS degrades cationic dyes within 18 min under energy efficient LEDs. • GC–MS analysis was conducted to deduce the degradation pathway of methylene blue. • High photodegradation ability of nanocomposites retained even after five recycles. Herein, type-II band alignment of magnetic ZnO/CuS has been achieved by assembling p-type CuS nanoparticles on n-type ZnO heterostructures to accomplish the photocatalytic degradation of two colored cationic dyes, namely, methylene blue (MB) and toluidine blue (TB). The material exhibited excellent photocatalytic efficiency towards MB and TB with 93% and 87.5% degradation in just 16 and 18 min respectively. The efficacy of doped photocatalyst (FSZCS) was found to be 6 times higher than the undoped material (Fe 3 O 4 @SiO 2 @ZnO; FSZ) whereas pristine CuS degraded only 50% of the dye sample under identical conditions. Therefore, the dramatic enhancement of the photocatalytic degradation performance could be attributed to the synergetic effect created by doping CuS over magnetic ZnO nanocomposites which extended the photoresponse of ZnO by driving the entire degradation process under visible light irradiation and also reducing the charge recombination rate. The plausible mechanistic pathway and identification of degradation products was discussed in detail on the basis of scavenger studies as well as GC–MS analysis. Furthermore, the designed catalyst could be recycled and reused up to 5 runs without any significant decrease in its photocatalytic activity. The reported procedure exhibited multiple advances as it proceeded by utilizing renewable household LEDs as power source at room temperature without the use of any additional oxidant under neutral pH conditions thus, paving a strong path towards sustainable, green and responsible chemistry. [ABSTRACT FROM AUTHOR]

Highlights: [•] Co3O4/BiOCl p–n heterojunction was synthesized by chemical coprecipitation method. [•] BiOCl nanoplates exhibits a high percentage of {001} facets exposure. [•] The heterojunction contains BiOCl nanoplates and Co3O4 nanoparticles. [•] The heterojunction shows excellent visible-light photocatalytic activity. [•] 0.8wt% Co3O4/BiOCl composite exhibits good cycle performance. [Copyright &y& Elsevier]

[Display omitted] Both electron and energy transfers contribute to the selective oxidation of sulfides with O 2 driven by green light over ARS–Ti-MCM-48. • Ti-MCM-48 with homogeneous dispersion of Ti species is synthesized. • Alizarin red S (ARS) embedded into Ti-MCM-48 can capture green light. • Selective oxidation of sulfide over ARS – Ti-MCM-48 advances steadily. • High selectivities of desired sulfoxides are achieved. • Both electron and energy transfers contribute to the transformation. Ti-containing mesoporous silica materials with a well-defined structure could give a clear picture of the elusive reaction pathways in photocatalysis. However, the dispersion of Ti sites usually results in their bandgaps being larger than that of TiO 2 , which makes the narrowing of bandgaps more challenging to construct visible light photocatalysis. Here, Ti-MCM-48 with an ordered cubic mesostructure and a homogeneous dispersion of Ti sites were successfully synthesized to embed an organic dye alizarin red S (ARS), affording a visible light photocatalyst ARS – Ti-MCM-48. The selective aerobic oxidation of sulfides into sulfoxides driven by green light over ARS – Ti-MCM-48 was accomplished directly. Notably, both electron transfer and energy transfer pathways were involved in the activation of O 2 , in which the Ti sites play a crucial role. Importantly, the photobleaching was effectively alleviated by embedding ARS into the mesopores of Ti-MCM-48. Moreover, high selectivities of desired sulfoxides were favorably achieved. In general, Ti-containing porous materials could be a unique scaffold for embedding photoactive molecules to carry out selective organic transformations driven by visible light. [ABSTRACT FROM AUTHOR]

A new and cost-effective photocatalyst was prepared via a facile modification of NH 2 -UiO-66 with an iron (III) complex i.e. Fe(acac) 3 , in order to enhance the optical properties and charge separation efficiency of pristine MOF. According to the results of UV-Vis DRS and Tauc plot calculations, the band gap value decreased from 2.7 eV to 2.46 eV for final Fe-UiO-66 photocatalyst, showing the improvement of light absorption in the visible region. Moreover, the photoluminescence (PL) and electrochemical impedance spectroscopies (EIS) confirmed the efficient separation of electron-hole carriers after introduction of Fe(acac) 3 into the MOF structure. The photo-Fenton reaction was carried out in the presence of photocatalyst and hydrogen peroxide under white LED illumination for degradation of organic dyes (methyl violet 2B, rhodamine B, malachite green, and methylene blue) and tetracycline (TC) as the examples of water pollutants. A significant dye and TC removal up to 92% and 85% were obtained in photo-Fenton system containing Fe-UiO-66 photocatalyst, respectively. The trap experiment using isopropyl alcohol (IPA) and Na 2 EDTA demonstrated that the major active species for pollutants degradation are hydroxyl radicals (•OH) and photo-generated holes (h+), respectively. Besides, the transfer of photo-generated electron (e-) to Fe(acac) 3 complex resulted in the reduction of Fe3+ to Fe2+ and acceleration of the photo-Fenton reaction. Also, the photocatalyst was found to be very stable during the photo-Fenton reaction according to physicochemical analyses, and it can be reused four times without remarkable decrease in activity. [Display omitted] • An economical Fe(acac) 3 complex was used to modify NH 2 -UiO-66 MOF. • This modification was performed by facile and one step Schiff-base reaction. • Optical properties and charge separation efficiencies of final photocatalyst were enhanced as compared to parent MOF. • Photo-Fenton degradation of dyes and tetracycline was examined. • This photocatalyst was found more efficient for removing these hazardous water pollutants. [ABSTRACT FROM AUTHOR]