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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]

[Display omitted] • Using BPO 4 as a new type of boron source, B/BiOCl was synthesized by a simple chemical deposition method, and the doping of B improves the adsorption performance and charge hole separation efficiency of BiOCl. • The photocatalytic degradation rates of the new B/BiOCl for RhB, MB and BF is 1.7 times, 3.6 times and 8.35 times those of BiOCl, respectively. • The novel B/BiOCl exhibits good performance in photocatalytic reduction of carbon dioxide, and its CH 4 production was increased to 3.21 times that of BiOCl. In this study, a fresh boron-doped B/BiOCl was produced utilizing BPO 4 as the boron origin. When exposed to visible light, B/BiOCl demonstrated effective degradation of organic dyes like Rhodamine B (RhB), methyl blue (MB), and basic fuchsin (BF). Their degradation rates surpassed those of BiOCl by 1.7 times for RhB, 3.6 times for MB, and 8.35 times for BF, respectively. Furthermore, the introduction of boron into B/BiOCl notably enhanced its photocatalytic reduction capability towards carbon dioxide, leading to a 3.21-fold increase in CH 4 production compared to BiOCl. Analysis results revealed a homogeneous distribution of boron within BiOCl, thereby improving its efficiency in charge-hole separation and adsorption. Consequently, the photocatalytic performance of B/BiOCl was significantly augmented. [ABSTRACT FROM AUTHOR]

[Display omitted] • The TiO 2 / N -GQDs (TGs) composite with hollow urchin-like structure was prepared. • The TGs can effectively expand the absorption spectrum of TiO 2 to visible light. • The TGs composite can efficiently degrade waste organic dyes under visible light. • The TGs composite has excellent stability and reusability. In order to enhance the visible light catalytic activity of TiO 2 by broadening its photoresponse range, the TiO 2 / N -GQDs (TGs) composite catalysts with a three-dimensional hollow urchin-like structure were prepared by one-step hydrothermal method. The microstructure and photoelectric properties of the synthesized TGs composites were analyzed through a series of characterizations, and the performance in degrading organic dyes under visible light was investigated. The results demonstrated that the prepared composites effectively enhanced the visible light absorption spectrum of TiO 2 by forming heterojunction. The degradation efficiency of organic dyes could reach 95.71% under visible light irradiation for 1 h, which further increased to 99.39% after 2 h. Additionally, the photocatalytic degradation process could be effectively accelerated under acid conditions. After 5 cycles of testing, the degradation efficiency of TGs composites on organic dyes was hardly reduced, indicating that they had great visible light catalytic activity and significant reusability. [ABSTRACT FROM AUTHOR]

Designing of an effectual heterostructure photocatalyst for catalytic organic pollutant exclusion has been the subject of rigorous research intended to resolve the related environmental aggravation. Fabricating p-n junctions is an effective strategy to promote electron-hole separation of semiconductor photocatalysts as well as enhance the organic toxin degradation performance. In this study, a series of n-type NiAlFe-layered triple hydroxide (LTH) loaded with various ratios of p-type MoS 2 was synthesized for forming a heterostructure LTH/MoS 2 (LMs) by an in situ hydrothermal strategy. The photocatalysts were characterized by XRD, SEM&EDX, TEM, FT-IR, XPS, as well as UV–vis DRS. The photoactivity of photocatalysts was tested by the degradation of Indigo Carmine (IC) dye. The optimized catalyst (LM1) degrades 100% of indigo dye in high alkaline pH under UV light for 100 min. Besides, the degradation rate of LM1 is 15 times higher than that of pristine NiAlFe-LTH. The enhanced photoactivity is attributed to the synergistic effect between NiAlFe-LTH and MoS 2 as well as the p-n junction formation. [Display omitted] • A facile method for synthesizing heterostructure-LMs photocatalyst is suggested. • The best photocatalytic performance was found in LM1 samples for dye degradation. • Superior adsorptive-photocatalytic activity of LM1 was revealed under visible light. • Photocatalytic performance of LMs was effectively exhibited even at high pH over 11. • The recyclability and mechanism of photocatalysis of LMs was identified. [ABSTRACT FROM AUTHOR]

• Preparation of pure ZnO and new Li-doped ZnO, Ag-doped-ZnO and Ag-Li doped ZnO nanocomposites materials by sol-gel method and thoroughly characterized. • Photodegradation of organic dye pollutants such as acid red-1 and mordant orange-1dyes and textile wastewater under visible light irradiation. • Mechanistic studies established that the active species are hydroxy radials via several scavengers' studies. The study describes the preparation and characterization of pure ZnO, Li-ZnO (LZO), Ag-ZnO (AZO) and Ag-Li-ZnO (ALZO) nanostructures by sol-gel method, followed by their application as photocatalysts for the degradation of dyes acid red (AR1), mordant orange (MO1) and textile wastewater (TWW) under irradiation of visible light. The ALZO composite showed the highest photocatalytic efficiency among the tested samples with 95% degradation of dyes, which was three times higher than that of pure ZnO. The degradation reaction followed pseudo-first-order kinetics and the control trapping experiments corroborated the reactive species are hydroxyl radicals. The study also investigated the influence of various operational parameters on the photodegradation of dyes. The high photocatalytic efficiency of the ALZO material is mainly due to its highly porous structure with greater surface area, enhanced absorption of visible light, and a decreased recombination rate of electron-hole pairs. The ALZO catalyst had a band gap energy of 2.82 eV and exhibited the wurtzite ZnO hexagonal phase. The study highlights the effectiveness of doping metal oxides into semiconductor oxides to enhance photocatalytic activity and suggests the potential of the ALZO composite as a promising photocatalyst for dye degradation. [ABSTRACT FROM AUTHOR]

[Display omitted] • A series of novel nanohybrids of g-C 3 N 4 /UiO-66 heterojunctions was synthesized. • The nanohybrids shows excellent activity in photocatalytic degradation of organic dyes. • Degradation rate of the nanohybrids is much faster than g-C 3 N 4 and UiO-66 alone. • The possible photocatalytic mechanism of RhB was proposed and confirmed. • DFT calculations were carried out to confirm the heterojunction structure and photocatalysis mechanism. In this research, a novel composite of typical Zr-based metal–organic frameworks (UiO-66) with porous graphitic carbon nitride (g-C 3 N 4) was prepared by an in-situ preparation method. The g-C 3 N 4 /UiO-66 nanohybrids (CNU-0.5chieved almost 100 % efficiency in the degradation of RhB (60 mg/L, 100 mL) within 70 min under visible light, which was 6.46 and 10.56 times faster than that of pure g-C 3 N 4 and UiO-66, respectively. The improved photocatalytic properties were attributed to the large surface area, enhanced optical adsorption ability and the creation of heterojunction between g-C 3 N 4 and UiO-66. The formation of the heterojunction structure enhanced the photoelectron transfer efficiency and reduced the recombination of electron/hole pairs. Furthermore, the trapping experiments showed that •O 2 –, h+ and •OH were the active species in the photodegradation process, with •O 2 – playing a dominant role. This study offers valuable insights into the preparation of MOF-based photocatalysts with exceptional effectiveness for the removal of contaminants in wastewater treatment. [ABSTRACT FROM AUTHOR]

Water, the most fundamental source of life, is contaminated by various organic pollutants, especially organic dyes from the dying industry. The photocatalytic degradation of malachite green (MG) was studied using a zinc-based metal-organic framework (Zn-BTC MOF) and ZnO. Thermally decomposing Zn-MOF synthesized ZnO and its structural and optical properties were analyzed using various spectroscopic techniques. This article focuses primarily on the wavelength-dependent photoluminescence properties of Zn-MOF and ZnO materials and their role in the photocatalytic degradation of MG dye in water. Zn-MOF and ZnO photocatalysts exhibited a photodegradation efficiency of approximately 99% after 40 min of visible light exposure. Based on kinetic experiments, the degrading efficiency of these catalysts followed pseudo-first-order reaction kinetics with a correlation of R2 = 0.99 and a rate constant of 0.031 min−1. This manuscript is helpful to researchers working on ZnO and Zn-MOF materials for photocatalytic and environmental applications. • Photoluminescence is an important and frequently reported property of Metal-Organic Frameworks (MOFs). • This communication is primarily concerned with the luminescence properties of Zn-MOF and ZnO materials. • Zn-MOF and ZnO role in the photodegradation of recalcitrants such as malachite green (MG) in water. • These catalysts displayed photodegradation efficiency of about 95% within 40 min. [ABSTRACT FROM AUTHOR]

• A modified reflux method was conducted to synthesize TiO 2 /MIL-100(Fe) composites. • TiO 2 /MIL-100(Fe) composites provide multifunction, including adsorption, photocatalytic and heterogeneous photo-Fenton reaction for removing organic dyes. • MIL-100(Fe) could be used as a supporter to fix TiO 2 and adsorb dyes due to its high specific surface area. • TiO 2 /MIL-100(Fe) composites could absorb visible light to conduct photocatalytic and heterogeneous photo-Fenton reactions simultaneously. • The kinetics analysis of dark adsorption and light reaction belonged to the pseudo-second-order model. Since TiO 2 photocatalysts were only ultraviolet-light-responsive and homogeneous photo-Fenton had some drawbacks in generating iron sludge, multifunctional TiO 2 /MIL-100(Fe) composites were synthesized to remove organic dyes under simulated solar light irradiation. Commercial TiO 2 and MIL-100(Fe) precursors were mixed in one pot using a modified reflux method in 12 h, 18 h, and 24 h to fabricate TiO 2 /MIL-100(Fe) with different weight ratios of the TiO 2 and Fe(NO 3) 2 precursors, including 0.07, 0.15, and 0.30. MIL-100(Fe) was used to efficiently distribute TiO2 and adsorb dyes due to its high specific surface area. Besides, TiO 2 /MIL-100(Fe) composites could absorb visible light to conduct photocatalytic and heterogeneous photo-Fenton reactions simultaneously. For the TiO 2 /MIL-100(Fe) composites (TF15-18), the individual kinetics analysis of removing organic dyes, including dark adsorption and light reaction, belonged to the pseudo-second-order model with the rate constants of 1.682 and 7.702 g·mg−1·min−1, respectively. The completed dye removal was achieved under 90 min dark adsorption and 180 min light reaction under the best conditions of pH=3.5 and 40 μL H 2 O 2 addition in 150 mL MB solution. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • Utilization of density functional theory (DFT) and time-dependent DFT calculations to achieve significant NIR absorption. • Discovery of a significant red-shift in dyes based on isoindigo derivatives with thiophene as the π-spacer. • Identification of fluorene as an effective donating group in dyes, which reduces charge recombination rates. In this study, we employed density functional theory (DFT) and time-dependent DFT (TD-DFT) calculations to optimize near-infrared (NIR) harvesting dyes, gaining deeper insights into their structure–property relationship, particularly for dye-sensitized solar cells (DSSCs). Our focus was on fine-tuning electron-donating and withdrawing groups within D-π-A metal-free organic dyes to enhance NIR absorption and achieve visually transparent DSSCs. Our research revealed a significant redshift in dyes based on isoindigo derivatives, with thiophene (TII) as the π-spacer. Dyes incorporating fluorene as the donor group effectively mitigated charge recombination rates, a key challenge in low-bandgap molecules. Notably, the TII1 dye, combining a fluorene donor with a TII π-spacer, exhibited maximum absorption at 654 nm and transmitted substantial visible light (500–600 nm), making it suitable for use in visually transparent DSSCs. These findings underscore the potential of the TII1 dye in significantly advancing the development of visibly transparent DSSCs. [ABSTRACT FROM AUTHOR]

Wastewater containing organic dyes is harmful to the ecological environment and human health. Graphitic carbon nitride (g-C 3 N 5) is suitable for the photocatalytic degradation of organic dyes, but its photocatalytic activity is low due to several drawbacks. A series of Ag–CeO 2 /g-C 3 N 5 composites with different morphologies of Ag–CeO 2 have been prepared in order to improve the photocatalytic activity of g-C 3 N 5. The photocatalytic activities of the Ag–CeO 2 /g-C 3 N 5 composites were investigated using rhodamine B (RhB) as the target pollutant. When compared with Ag–CeO 2 spheres and g-C 3 N 5 , the charge separation efficiency and photocatalytic activity of the Ag–CeO 2 /g-C 3 N 5 heterostructure were significantly improved. The photodegradation rate of RhB using 50 wt% Ag (1.50)-CeO 2 (sphere)/g-C 3 N 5 was 96.5 %, while pure g-C 3 N 5 and Ag (1.50)-CeO 2 spheres was 30.8 and 9.9 %, respectively. This was attributed to the synergistic effect of the heterojunction comprised of Ag, CeO 2 , and g-C 3 N 5. As an electronic medium, Ag transfers electrons between g-C 3 N 5 and CeO 2 , which can promote electron-hole separation and improve the photocatalytic activity. The 50 wt% Ag (1.50)-CeO 2 (sphere)/g-C 3 N 5 composites also had fair photocatalytic stability and · O 2 − plays a dominant role in the RhB photodegradation process. In addition, the photocatalytic mechanism of 50 wt% Ag (1.50)-CeO 2 (sphere)/g-C 3 N 5 has also been described. [Display omitted] • Series Ag–CeO 2 /g-C 3 N 5 composites were synthesized with respective morphologies of Ag–CeO 2. • Loading Ag–CeO 2 on g-C 3 N 5 can improve the specific surface area and photocatalytic property. • The photodegradation to RhB of 50 wt% Ag–CeO 2 /g-C 3 N 5 composites can reach 96.5 % within 150 min. • The 50 wt% Ag–CeO 2 /g-C 3 N 5 composites have good photocatalytic activity and chemical stability. [ABSTRACT FROM AUTHOR]

In pursuit of the appropriate method for complete removal of organic effluents from surface water, Ag modified g-C 3 N 4 materials as a photocatalyst gained considerable attention. In this paper, Ag doped g-C 3 N 4 materials were prepared by a facile one-pot pyrolysis method. The synthesized photocatalysts were studied using different analytical techniques like XRD, HR-TEM, XPS, UV, FTIR, PL spectroscopy, etc. The prepared photocatalyst materials were used for the visible light photodegradation of IC dye as an organic pollutant and for self-cleaning applications. The obtained results indicate that the optimized Ag doped g-C 3 N 4 (CNA-1) sample exhibits 79.97 % degradation efficiency in 30 min with efficient self-cleaning performance. The enhanced photocatalytic activity of CNA-1 can be attributed to the incorporation of Ag, which plays a pivotal role in absorbing visible light. Furthermore, cycling tests were employed to evaluate the stability and reusability of material. The possible photocatalytic mechanism was proposed from trapping experiments. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • Three structurally simple D-A-π-A dyes were synthesized for DSSCs. • The effects of electron donor groups on photovoltaic performance were investigated. • DSSC based on diphenylamine donor achieved the highest PCE of 5.01 %. • By co-sensitizing appropriate dyes, a PCE of 5.49 % was achieved. Three structurally simple metal-free organic dyes (C1 , C2 and C3) with D–A–π–A structure, having benzothiadiazole auxiliary acceptor, benzene π-bridge and cyanoacrylic acid anchoring group, were designed and synthesized for use in dye-sensitized solar cells (DSSCs). Diphenylamine, carbazole and phenothiazine were used as electron donor groups and their effects on the photovoltaic performance were investigated. It was found that C1 dye with diphenylamine donor has the longest maximum absorption wavelength and highest molar extinction coefficient, which is benefical for harvesting more photons and generating a higher photocurrent. Therefore, the DSSC based on C1 dye gives a power conversion efficiency (PCE) of 5.01 %, which is greater than those of C2 dye with carbazole donor (3.51 %) and C3 dye with phenothiazine donor (1.76 %). Finally, the co-sensitization of C1 and C2 exhibits a highest PCE of 5.49 % may be due to broader visible light absorption. [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]

α–β Bi2O3 modified with Cu2+ ions in various compositions have been synthesized by hydrothermal process. The crystallinity, surface structure, elemental compositions and optical characteristics were uncovered by relevant techniques including XRD, SEM, EDX, XPS, PL, and UVDRS. Total organic carbon (TOC) analysis was performed to determine the dye degradation efficiency of photocatalyst. Highly crystalline Bi2O3 nanoparticles consisting of α–β phase heterojunctions were observed possessing crystallite sizes in the range of 30–40 nm. The photocatalytic activity of Cu2+-modified Bi2O3 composites was studied using RhB dye under the illumination of visible light. The results reveal that addition of Cu2+ ions into Bi2O3 lattice significantly improved the degradation rate over the pure sample. The highest activity was obtained for sample containing 2 mol % Cu in Bi2O3 lattice where complete degradation of the pollutant was attained in 120 min. The increased activity is largely ascribed to the effective separation of charge carriers due to Cu2+ doping and formation of α–β phase heterojunctions in Bi2O3.The effect of pH conditions and role of active species on degradation kinetics were also examined. [ABSTRACT FROM AUTHOR]

As competitive photocatalysts, Cu 2 O nanoparticles meet with severe photogenerated carries recombination and insufficient light absorption, leading to the poor photocatalytic performance. Herein, the truncated Cu 2 O-Au (CA) binary and Cu 2 O-Au-TiO 2 (CAT) ternary octahedra with Au nanoparticles (Au NPs), preferentially supported on the (110) and (100) planes of Cu 2 O, are synthesized for efficient photocatalytic degradation reactions. The photodegradation rates of MO of CA1 (Cu 2 O-Au containing 1 wt % Au) and CAT are as high as 95.61% and 96.5% under 60 min of visible light irradiation, respectively. On the one hand, the synergistic function of localized surface plasmon resonance (LSPR) of Au NPs and Schottky barrier accelerate the separation and transfer of photogenerated carriers. On the other hand, a Z-scheme electron transfer system is constructed in CAT to promote the photodegradation performance. According to the finite-difference-time-domain (FDTD) simulation result, there is a strong electric field enhancement at the contact sites between Au, Cu 2 O and TiO 2 , which accelerates the electron transfer to a large extent and separates the electron-hole pairs. Therefore, this work may provide an approach for the synthesis and applications of multiple heterostructure catalyst. [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]

Novel photolithography using NIR (Near Infrared) exposure and its photoresist are developed. Using NIR's extreme high transparency to photoresist polymer layer, photoresist with very high photosensitivity and vertical profile can be achieved. Combination with organic black pigment that blocks UV/visible light but is transparent to NIR, black photoresist with vertical profile and high film thickness can be made. [ABSTRACT FROM AUTHOR]

In this study, the self-cleaning and photocatalytic properties of clay bricks fired under various temperatures under visible light were addressed. Within this framework, the photocatalytic performance together with adsorbance properties of clay bricks fired at 900 °C, 1000 °C, and 1100 °C were evaluated by means of a UV–vis spectrophotometer. It revealed from the experimental data that fired clay bricks exhibited self-cleaning properties as they were observed to be able to remove the methylene blue (MB) dye as an organic pollutant. The best performance in terms of total degradation efficiency and apparent reaction rate of MB was recorded by the clay brick fired at 900 °C as 90.57% and 0.3039 h−1, respectively. Additionally, it was also confirmed that the physical properties that change with the firing temperature have a great effect on the removal of MB as well as semiconductor content within the brick. [ABSTRACT FROM AUTHOR]

In recent years, there have been many research works on use of different methods to treat textile dyeing wastewater such as mechanical, biological and chemical methods (using oxidizing agents, such as: H2O2, O3, and H2O2/O3). However, some traditional textile dyeing wastewater treatment methods such as mechanical and biological methods have limitations in treating these pollutants thoroughly. To enhance the treatment efficiency, the use of photocatalysts combination with strong oxidizing agents, such as H2O2, has been extensively developed in recent years. In this study, the iron-centred bimetallic organic framework Fe-MOF has been synthesized by partial replacement of Fe3+ ions with Mn metal ions by solvent-thermal method. The analytical methods used to evaluate the structural characterization of the as-synthesized materials including Scanning Electron Microscope (SEM), Brunaurer-Emmett-Teller (BET), X-ray Diffraction (XRD), Fourier Transform Infra Red (FT-IR), and UV-Vis Diffuse Reflectance Spectroscopy (DRS). The experiments on the decomposition of organic pigment Rhodamine B were performed under varying conditions of pH, catalyst mass and RhB colorant concentration. Experiments with different electron capturers indicate that h+ plays a major role in the photochemical degradation of RhB. The stability and durability of the 0.1 Mn/Fe-MOF catalyst were evaluated through the leaching and recycle experiments, showing that the RhB degradation efficiency of the photocatalyst decreased modestly after five repetitions. [ABSTRACT FROM AUTHOR]

Aiming at exploring an effective photocatalytic adsorbent for organic dye removal, a series of heterostructured TiO2@HKUST-1 photocatalysts, by incorporating HKUST-1 with different TiO2 nanoparticles loading, were prepared by single-step hydrothermal method. The morphology and surface characteristics of the as-prepared TiO2@HKUST-1were analyzed using SEM, HRTEM, XRD, FTIR, UV–vis DRS, and Photoluminescence techniques. The adsorption-photocatalytic degradation of the model dye methylene blue (MB) on the catalysts was investigated. It was indicated that the introduction of a certain amount of TiO2 on the surface of HKUST-1 could improve the transfer and separation of the photogenerated charge carriers, resulting in the enhanced photocatalytic activity. The optimal 0.02TiO2@HKUST-1 exhibited the highest MB removal rate with about 4.4 and 19.3 times as high MB removal efficiency as that of HKUST-1 and TiO2, respectively. Heterostructured TiO2@HKUST-1 materials for the removal of MB involved the integrated adsorption and visible light photocatalysis. Meanwhile, the composite exhibited good reusability in the process of cyclic experiments. Therefore, this work provides a potential MOF-based photocatalytic adsorbent for organic dye removal. [ABSTRACT FROM AUTHOR]

Net-stacked hierarchical CdOHF architectures were controllably synthesized via a simple hydrothermal method. The SEM and TEM results show that the hierarchical CdOHF structure is made up of many CdOHF nanobelts. Different pH values and reaction times make the CdOHF feature adjustable structural variations with 1D nanobelts, nanobelt-woven 2D nets and net-stacked 3D hierarchical structures. With a first-order reaction rate constant that was 5 times higher than those of other CdOHF morphologies, the obtained net-stacked hierarchical CdOHF architectures exhibited high efficiency and selectivity for degrading the cationic dye malachite green (MG) under visible light irradiation, for example, the decolorization rate for MG (40 mg L−1) solution reached approximately 100% within 30 min. Moreover, the hierarchical CdOHF also displayed good photochemical stability for the degradation of MG after five recycles. The improved photocatalytic efficiency of the 3D net-stacked hierarchical CdOHF is ascribed to the synergistic effects of the porous hierarchical architectures, narrower band gap energy and large BET surface areas. This work provides a simple and feasible strategy for controllable synthesis of 3D hierarchical micro/nanomaterials with high performance, and such inexpensive high-performance hierarchical CdOHF architectures can find potential applications for the degradation of organic dyes. [ABSTRACT FROM AUTHOR]

Ethynylbenziodoxolones (EBXs) are commonly used as radical traps in photocatalytic alkynylations. Herein, we report that aryl‐substituted EBX reagents can be directly activated by visible light irradiation. They act as both oxidants and radical traps, alleviating the need for a photocatalyst in several reported EBX‐mediated processes, including decarboxylative and deboronative alkynylations, the oxyalkynylation of enamides and the C−H alkynylation of THF. Furthermore, the method could be applied to the synthesis of alkynylated quaternary centers from tertiary alcohols via stable oxalate salts and from tertiary amines via aryl imines. A photocatalytic process using 4CzIPN as an organic dye was also developed for the deoxyalkynylation of oxalates. [ABSTRACT FROM AUTHOR]

Cu 2 O nanoparticles have been anchored on the surface of Bi 4 O 5 Br 2 hollow nanocubes, and the resulting composites have been tested for the photocatalytic degradation of organic dyes under visible light. The as-synthesized composites are composed of Bi 4 O 5 Br 2 in the monoclinic phase and Cu 2 O in the cubic phase, both of which respond to visible light. The optimized Bi 4 O 5 Br 2 /Cu 2 O composite can decompose 95% of initial RhB and 99% of initial MB after 80 min illumination, which is significantly higher than those obtained on bare Bi 4 O 5 Br 2 and Cu 2 O photocatalysts. The charge transfer and separation dynamics in the Bi 4 O 5 Br 2 /Cu 2 O composite photocatalysts under excitation are proved to be superior compared to bare Bi 4 O 5 Br 2 in the electrochemical measurements. The enhanced performance of the Bi 4 O 5 Br 2 /Cu 2 O composite is attributed to the p-n junction formed between Bi 4 O 5 Br 2 and Cu 2 O, which inhibits charge recombination and facilitates effective charge separation. Lastly, it has been proved in the scavenger tests that superoxide radical is the most crucial active species in the photocatalytic degradation of RhB. [ABSTRACT FROM AUTHOR]

In this study, flake-like MoO3-ZnO composite was prepared using a simple and robust electrochemical setup. The composite was characterized by X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, elemental analysis, X-ray photoelectron spectroscopy, thermogravimetric analysis, photoluminescence, zeta potential analysis, and electrochemical impedance study. The modified ZnO shows a remarkable catalytic activity towards the photodegradation of three potentially hazardous dyes, malachite green, crystal violet, and methylene blue. More than 95% of both malachite green and crystal violet degraded within 140 min under visible light irradiation. Scavenger studies reveal that OH· radicals produced by the photo-separated charges on MoO3-ZnO are responsible for the degradation of all three dyes. The photoactive charge carriers show less recombination rate as evidenced by the photoluminescence spectrum due to the interparticle charge migration process. This work suggests a new versatile procedure for the synthesis of MoO3-ZnO composites and establishes its photocatalytic efficacy under visible light with three common pollutant dyes found in wastewater. [ABSTRACT FROM AUTHOR]

A novel magnetic Fe3O4@SiO2@Bi2O2CO3/rGO composite comprising of uniform core-shell-structured Fe3O4@SiO2@Bi2O2CO3 microspheres mounted on reduced graphene oxide (rGO) sheets was successfully fabricated by using a facile hydrothermal method. The adsorption–desorption isotherm of Fe3O4@SiO2@Bi2O2CO3/rGO belonged to type IV with an H4-type hysteresis loop. The specific surface areas and magnetization saturation value (Ms) of Fe3O4@SiO2@Bi2O2CO3/rGO (x = 0.15 g) were 102.12 m2/g and 25.4 emu/g, respectively. Fe3O4@SiO2@Bi2O2CO3/rGO (x = 0.15 g) exhibited remarkable photocatalytic degradation activity and mineralization effect for MO and decolorization performance for the mixed solution of MO, Rh B, and MB. MO degradation by Fe3O4@SiO2@Bi2O2CO3/rGO conformed to a first-order kinetic reaction, and the corresponding kapp value was 0.05553 min−1. A suitable amount of rGO in Fe3O4@SiO2@Bi2O2CO3/rGO could decrease the energy band gap, inhibit the recombination of photo-induced electron/hole (e−/h+) pair, and broaden and enhance the response of the catalyst to visible light, thereby enhancing the visible-light catalytic degradation of organic dyes. The active species produced in the photocatalysis included •O2−, •OH, and h+, with •O2− being the dominant active species. The as-prepared photocatalyst also showed excellent magnetic separation performance and stability. Results show that the as-prepared Fe3O4@SiO2@Bi2O2CO3/rGO composite is a promising photocatalyst with considerable application potential in organic dyes removal. [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]

New benzothiadiazole-based long-wavelength organic dyes (Y-1 and Y-2) were prepared for effectively sensitizing diphenyliodonium hexafluorophosphate (IOPF) to initiate the fast curing of bisphenol-A epoxy resin (E51) under visible light, avoiding traditional UV light sources that have high energy and high radiation. Y-1 and Y-2 have absorption spectra extended to more than 550 nm. By using Y-1 and Y-2 as photosensitizers for IOPF, E51 reach high epoxy conversions of 95% under light wavelength of 470-nm irradiation. IOPF and benzothiadiazole dyes present at the same time show good visible-light initiating activity. The high curing conversions are attributed to the photoelectron transfer reaction between diphenyliodonium hexafluorophosphate and benzothiadiazole dyes, based on our photochemical and electrochemical experiments. In addition, the terminated groups or of Y-1 (–F) and Y-2 (–OCH3) have a great influence on the photopolymerization rate of the curing systems and thermal properties of E51 after cured. In addition, E51 was even polymerized about 70% in the presence of 510-nm light filter. [ABSTRACT FROM AUTHOR]

This study reports a green approach for the modification of titanium dioxide (TiO2) nanoparticles with immobilization of silver nanoparticles. One of the natural sources i.e., Mangifera indica leaf extract was utilized as reducing and capping agent for the fabrication of Ag-TiO2 nanocatalyst. Further, the surface morphology and band-gap energy of prepared Ag-TiO2 were analyzed by Scanning Electron Microscopy (SEM), Energy Dispersive X-ray Spectroscopy (EDS) and UV–Vis spectroscopy. Also, it was characterized by X-ray Powder Diffraction (XRD) which provides the information regarding the crystallinity of the Ag-TiO2. Subsequently, photo activity of Ag-TiO2 was investigated for the degradation of methylene blue (MB) dye wastewater through visible light driven photoreactor. The Ag-TiO2 provided highest (68%) of photo-degradation efficiency within 110 min for 7.81 × 10−5 mol/L initial MB concentration at pH 8 by using 0.19 g/L photocatalyst. Further, addition of 10 mM H2O2 boost up the MB photodegradation to 74%. The kinetic study confirmed the MB degradation followed first order rate of reaction. [ABSTRACT FROM AUTHOR]

In this research, carbon nanotube (CNT)-modified plasmonic silver-strontium titanate (Ag@ SrTiO 3) nanocomposites for the degradation of the organic dye were prepared by the sol-gel method. The characterization of all products was carried out using the X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), N 2 adsorption-desorption test (BET), field emission-scanning electron microscopy (FESEM), transmission electron microscopy (TEM), UV–visible diffuse reflectance spectroscopy (DRS), photoluminescence (PL) spectroscopy, electrochemical impedance spectroscopy (EIS), and transient photocurrent (TPC) studies. It was found that the incorporation of Ag in and introducing CNT into the SrTiO 3 nanoparticles reduced the crystallite size to 21 nm and the band gap energy to 2.7 eV. The Reduced PL peak intensity, increased photocurrent value, and reduced charge transfer resistance approved that the Ag@SrTiO 3 @CNT nanocomposite had a greater charge transfer efficiency than other samples. The optimal dosage of the photocatalyst, for the complete degradation of 5 ppm of the methylene blue (MB) solution after 30 min of the visible light irradiation, was decided as 0.5 g/L. Besides, in the experimental environment, the Ag@SrTiO 3 @CNT sample illustrated the most significant photocatalytic performance of the degradation of methyl orange (MO) and Rhodamine B (RhB) dyes. The detailed mechanism and kinetics of the degradation procedure were clarified. Finally, the prepared system displayed increased stability and reusability in the entire cyclic degradation experiment. [ABSTRACT FROM AUTHOR]

In this work, a highly stable Fe-MOF, namely [Fe2(OH)2(BPTC)]·2DMF·2H2O (JOU-22, H4BPTC = biphenyl-3,3′,4,4′-tetracarboxylic acid, DMF = N,N-dimethylformamide), was solvothermally synthesized using lanthanum nitrate and HF as modulators. Single-crystal diffraction shows that JOU-22 reveals a 3D microporous framework based on Fe–O chains. Due to its high chemical stability, suitable band gap (2.1 eV), and appropriate HOMO (−0.21 V) and LUMO (1.89 V) energy, JOU-22 shows efficient visible-light induced photocatalytic activity for Cr(VI) reduction and dye degradation. JOU-22 can also be used for the degradation of organic dyes, including MB, MO, BG and RhB. Fascinatingly, in the mixed system with the co-existence of dichromate anions and MB, the degradation rate of both Cr(VI) and MB increased significantly due to the synergistic effect between the photocatalytic reduction and oxidation process. This work not only provides a new clue for the preparation of large-size Fe-MOF single crystals, but also enriches the application of Fe-MOFs in the treatment of water pollution. [ABSTRACT FROM AUTHOR]

The molecular structure, UV-visible spectra, and optical properties of D-π-A conjugated organic dye molecules (Disperse Red 1 (DR1) and Disperse Red 73 (DR73)) were analyzed using density functional theory (DFT) and time-dependent density functional theory (TD-DFT) and compared with azobenzene molecule to study the effect of donor and acceptor substituents on the molecular properties. The performance of DFT functionals is investigated using B3LYP hybrid functional and three long-range corrected functionals (CAM-B3LYP, LC-ω PBE, and ω B97XD) in conjunction with 6-31G(d,p) basis set. Using TD-DFT, we calculate the vertical excitation energies and transition dipole moment values for 100 excited states. These values were further utilized to calculate frequency dependent polarizability under sum-over-states (SOS) formalism and refractive index of these molecular systems. We observe that for azobenzene and DR1 molecules, ω B97XD predicted wavelengths corresponding to peak absorbance closest to the experimental results, while for DR73 molecule, B3LYP gave better prediction. Large polarizability response is also observed for these molecules (DR1 and DR73) in comparison to parent azobenzene structure due to charge transfer between donor and acceptor groups. For DR1 and DR73 molecules, αxx component of polarizability dominates in contrast to azobenzene where αyy dominates. The HOMO → LUMO transition during excitation contributes to the peak molecular response in simulated UV-visible spectra. The high polarizability response of selected D-π-A conjugated molecules in comparison to parent molecule suggests that these molecules are promising candidates for tailor-made photonic and optoelectronic device development. [ABSTRACT FROM AUTHOR]

[Display omitted] • Sb 2 MoO 6 nanoparticles were anchored over g-C 3 N 4 nanotube by a facile reflux method. • The binary photocatalyst illustrated the highest activity in degradation of various pollutants. • Activity was 88.4-folds premier than g-C 3 N 4 in tetracycline degradation under visible light. • Activity was 48.3-times superior than g-C 3 N 4 in RhB degradation under visible light. • The photocatalyst displayed activity of 21.8-times larger than g-C 3 N 4 in Cr (VI) photoreduction. The development of high-efficiency photocatalysts is an attractive strategy for pollutants degradation under visible light. Herein, novel photocatalysts are reported through coupling Sb 2 MoO 6 with g-C 3 N 4 nanotube (abbreviated as GCN nanotube) by a simple reflux method. Also, the nanocomposites were defined by applying various analyses. Under visible-light excitation, the GCN nanotube/Sb 2 MoO 6 systems had more photoactivity than g-C 3 N 4 (abbreviated as GCN) and the rate constant for RhB removal on optimal GCN nanotube/Sb 2 MoO 6 (30%) nanocomposite was 48.3 times premier than the GCN. Also, compared to the pristine GCN, the GCN nanotube/Sb 2 MoO 6 (30%) sample demonstrated supreme photoactivity towards tetracycline degradation and Cr (VI) photoreduction, which was 88.5 and 21.8 times higher than the bulk GCN, respectively. These impressive enhancements were attributed to the quick segregation of charge carriers, boosted visible-light absorption, and extended specific surface area. Moreover, the photocatalyst has enough activity after four successive cycles. Finally, a conceivable charges transfer route is presented through n-n heterojunction constructed between Sb 2 MoO 6 and GCN nanotube. [ABSTRACT FROM AUTHOR]

By using tritopic and ditopic organic linkers derived from the same 2,4,6‐triphenylpyridine core, copper(II) metal‐organic frameworks with different three‐dimensional structures have been successfully synthesized under ambient conditions. The crystalline framework, PTBMOF ([Cu3(PTB)2(H2O)3]n, where H3PTB=4,4′,4′′‐(pyridine‐2,4,6‐triyl)tribenzoic acid, was observed to be mesoporous in nature and exhibited dual functionality in the removal of organic dyes. While cationic dyes such as methylene blue and malachite green, which are of different sizes, were adsorbed by PTBMOF; anionic dyes such as tartrazine could be effectively degraded in a photo‐Fenton‐like reaction catalyzed by the MOFs under irradiation with visible light. [ABSTRACT FROM AUTHOR]

The pyrolysis of melamine was an effective one-pot method for preparing a nanostructured multifunctional photocatalytic based on core/shell g-C3N4@TiO2 heterojunction. Various techniques entirely characterized these materials: X-ray diffraction (XRD) proved to enhance the as-prepared materials' crystallinity through the variation of dislocation, strain, and crystallite size with TiO2 loading. The stacked layered/sheet-like with a smooth surface of the as-prepared samples have been shown via scanning electron microscopy (SEM). Diffuse reflectance spectroscopy (DRS) showed an apparent decrease in the energy bandgap for these nanocomposites with TiO2 loading. All the prepared materials were subjected to visible photocatalytic applications under the same conditions. The dye model (Methylene Blue, MB), and antibiotic model (Amoxicillin, AMO), was photodegraded using the as-prepared nanocomposites under visible light irradiation. In the recombination reduction among TiO2 and g-C3N4 interfaces, g-C3N4 has been effectively utilized as a matrix. Our findings proved that g-C3N4@TiO2 photocatalysts exhibited superior photocatalytic performance. CNT-5 of 2.58 eV bandgap had a higher activity of 99.7 in 50 min for MB and 100% in 20 min for AMO than the other represented photocatalysts in this work. The migration of photogenerated electrons from a g-C3N4 to TiO2 via heterojunction among them as g-C3N4 (1 0 1) removes the electrons accumulated on (1 0 1) of TiO2, improve the photodegradation efficiency. Therefore, the increase in photocatalytic reaction rates, recycling, and the sample's photostability can be considered the result of successful interactions among the TiO2 and g-C3N4 systems. The suggested photodegradation mechanism of MB and AMO was discussed in detail and compared with previously reported work. Therefore, the photodegradation rate of MB and AMO via CNT-5 composite is 6 and 3 times, respectively, higher than that of g-C3N4 under simulated solar irradiation. This research creates a new perspective on the production of nanocomposite materials in the area of treatment of pharmaceutical and dye contaminants. [ABSTRACT FROM AUTHOR]

By serving as alternatives to toxic and hazardous solvents, green solvents assist in implementing the idea of sustainability. The use of these neoteric reaction media dramatically reduces energy requirements and moderates the rate at which chemical waste is produced. In this work, we propose the sustainable synthesis of AFe2O4 catalyst (A = Mg, Zn, Mn) using a deep eutectic solvent (DES) mixture. The choline chloride–malonic acid based DES system shows heterogeneities at the nanoscopic stage, allowing for a more holistic production of spinels via a modified solid-state route with less environmental effect. Structural and morphological analyses of the synthesized ferrites clearly demonstrate the importance of next-generation solvents in the fabrication of functional materials. The ability of these synthesized samples to act as magnetically separable catalysts for the effective degradation and electrochemical detection of hazardous dye contaminants in water bodies using visible light has also been investigated. This approach quantifies green chemistry metrics and proves that functional materials can be effectively modified and improved at the nanoscale for a variety of applications. [ABSTRACT FROM AUTHOR]

Ultrafine NiAl2O4 nanoparticles were prepared by simple one-pot chemical precipitation route. The precursor materials used were nickel nitrate hexahydrate and aluminum nitrate nonahydrate (as the basic materials) and sodium hydroxide (as a precipitator material). In a typical experiment, aqueous nitrate solutions were added drop wise to the alkaline solution in a magnetic stirrer under stirring. The resultant dark green colored precipitate was washed with water/ethyl alcohol (1:1 v/v) and dried. Finally, the sample was heat treated at 800 °C for 3 h in order to get the phase pure product. The prepared NiAl2O4 nanoparticles were characterized by XRD, FTIR, particle size analysis, SEM and UV. The band gap energy (Eg) of NiAl2O4 was found to be 3.05 eV. The photocatalytic degradation of malachite green and methylene blue over NiAl2O4 under visible light was carried out and the obtained results were discussed in this article. [ABSTRACT FROM AUTHOR]

A novel cobalt-based coordination polymer generates superoxide radicals under visible light to accelerate photocatalytic degradation of organic dyes. [Display omitted] It is crucial to construct an effective photocatalyst for the removal of dyes from aqueous environments. In the present work, a novel cobalt-based coordination polymer was synthesized and characterized with the molecular formula [Co(ipa)(ptt)] n (Co-CP), (ipa = isophthalic acid, ptt = 5-(4-Pyridyl)-1H-tetrazole). In Co-CP , each cobalt ion is in a six-coordination mode and is connected to two adjacent ligands to form a three-dimensional network structure. Furthermore, Co-CP excellent degradation properties and can effectively degrade methylene blue (MB) and rhodamine B (Rh B) under visible light with degradation efficiencies of 84.3 % and 94.6 %, respectively. Additionally, its PXRD patterns and FTIR spectra remained consistent with the original complex after three cycles, which proved that it was very stable, and there was no significant decrease in degradation ability after three cycling cycles, indicating its excellent reusability. The photocatalytic degradation mechanism was subsequently rationalized through free radical trapping experiments and analysis the energy band structure of Co-CP. [ABSTRACT FROM AUTHOR]

Peroxymonosulfate (PMS)-based advanced oxidation processes have been widely concerned because of their efficient treatment and wide applicability for the removal of various organic pollutants. In this study, ZnCo layered double hydroxide (ZnCo-LDH) were prepared by the hydrothermal method, analyzed by several characterization methods, and tested as a heterogeneous photoactivator to activate PMS for the removal of refractory organic dyes. The experimental results showed that 3D multi-layered ZnCo-LDH (1:1) catalyst can activate PMS to achieve the main degradation of 10 mg L-1 rhodamine B (RhB) under dark within 40 min. Moreover, the RhB can be completely degraded within 30 min by supplying the additional visible light under the same conditions. It can be seen that all degraded reaction processes were corresponded with the pseudo-first-order kinetic model, and the highest rate of RhB removal is 0.1303 min-1 in visible light. The effect of various conditions including the reaction system, inorganic anions, and initial pH on the RhB degradation was analyzed in detail. The ZnCo-LDH (1:1) catalyst can still keep high catalytic activity to PMS and achieved more than 95% degradation efficiency even after continual four recycles. In addition, the reaction mechanism indicated that hydroxyl radical (•OH) and sulfate radical (SO4 •-) can effectively oxidize RhB by the single activation of ZnCo-LDH catalyst, and this reaction process can also be enhanced under visible light irradiation. Briefly, the heterogeneous PMS-AOPs synergistic techniques could be a promising work for the integrated control of environmental pollution. [ABSTRACT FROM AUTHOR]

The layered Bi3O4Br nanoplates were synthesized through a simple calcination process, which can simultaneously harvest visible light and ultrasonic vibration to realize the effective piezo-photocatalysis. The piezo-photocatalysis over the Bi3O4Br leads to a great enhancement in catalytic efficiency with respect to the pure photocatalysis or piezocatalysis. The apparent rate constant of piezo-photocatalysis for the degradation of MO achieves to be 0.008 min − 1 , which is 5.20 and 1.51 times as high as the individual piezocatalysis and photocatalysis, respectively. This enhancement would be attributed to the built-in piezoelectric field induced by ultrasonic vibration facilitating the separation of charge carriers in photoexcited Bi3O4Br. [ABSTRACT FROM AUTHOR]

• 3D hollow ZIF-67 MOF based photocatalyst with excellent photo-catalytic performance was synthesized. • The H-ZIF-67@PDA@TiO 2 sample exhibited strongest photo-current intensity. • The photodegradation kinetic follows the Langmuir-Hinshelwood (L-H) model. • Superoxide free radicals (•O 2 −) and hydroxyl radicals (•OH) were the primary and secondary reactive species during photo-degradation. Photocatalytic technology is considered the most promising green technology for the degradation and removal of organic pollutants. In this paper, an innovative multifunctional photocatalytic material has been successfully prepared. The zeolitic-imidazolate-framework-67 (ZIF-67) was first synthesized by an easy and green approach. Then, a polydopamine (PDA) mid-layer was incorporated on its surface via dopamine self-polymerization, which not only serves as a stable linking agent, but also increases the amount of visible light captured and reduces the recombination of photogenerated electron-hole pairs. After the hydrolysis and hydrothermal process of tetrabutyl orthotitanate, the TiO 2 nanoparticles were uniformly grafted on the surface, and finally, the hollow ZIF-67@PDA@TiO 2 was successfully obtained. The prepared H-ZIF-67@PDA@TiO 2 photocatalyst was characterized by various techniques, and further used for the photo degradation of a variety of dyes in wastewater in the presence of visible light. A degradation rate of almost 100% was achieved for Acid Fuchsin and Congo Red within 40 min, followed by Erythrosine B and Rose Bengal with a 99% degradation rate within 150 min. Moreover, the ZIF-67-based photocatalyst exhibited high stability and recyclability and maintained an excellent photocatalytic performance during continued cycling. Furthermore, the superoxide radical (•O 2 −) and the hydroxyl radical (•OH) were the primary and secondary reactive species during photodegradation. Overall, the excellent performance of this simple photocatalyst was clearly demonstrated, and its numerous advantages, such as low energy consumption, low cost, non-toxicity, and environmental friendliness, showing promising potential for its practical implementation. [Display omitted] [ABSTRACT FROM AUTHOR]

In this work, we present a new synthetic strategy for fourfold‐substituted perylene monoimides via tetrabrominated perylene monoanhydrides. X‐ray diffraction analysis unveiled the intramolecular stacking orientation between the substituents and semicircular packing behavior. We observed the remarkable influence of the substituent on the longevity and nature of the excited state upon visible light excitation. In the presence of poly(dehydroalanine)‐graft‐poly(ethylene glycol) graft copolymers as solubilizing template, the chromophores are capable of sensitizing [Mo3S13]2− clusters in aqueous solution for stable visible light driven hydrogen evolution over three days. [ABSTRACT FROM AUTHOR]

Herein, we report the novel metal organic frameworks (MOFs)-based polypyrrole (TiO2/Cu-MOF/PPy) composite via facile hydrothermal technique. The prepared composites are characterized by X-ray diffractometer; microstructural characterization is done with field emission scanning electron microscopy (FESEM); and Fourier-transform infrared spectroscopy, X-ray photo-electron spectroscopy, UV–Vis absorbance spectra, and UV–Vis diffuse reflectance spectra analysis are obtained. The catalytic behavior is examined through the decomposition of methylene blue, rhodamine B, and methyl orange, as a standard dyes under visible light irradiation. Enhanced photocatalytic activities for the novel TiO2/Cu-MOF/PPy composite under visible light are attributed to the high charge separation, absorption, and carrier mobility of MOFs-based polypyrrole composite. Our result shows a great potential of MOFs-based polymer materials as catalyst under visible light radiation for the decomposition of industrial organic dyes. [ABSTRACT FROM AUTHOR]

An efficient visible light-responsive TiO2/graphene composite was synthesized easily by grinding. The structure and morphology of the composite were characterized by powder X-ray diffraction, Raman spectroscopy, ultra-high-resolution transmission electron microscopy, and field emission scanning electron microscopy. The photocatalytic characteristics were studied by degrading methylene blue under different conditions such as pH, catalyst dosage, different wt.% ratios of TiO2/ graphene composites, irradiation time, and initial concentration of methylene blue. The results showed that the TiO2/2.0% graphene possessed much higher photocatalytic activities under visible light than pure TiO2, displayed high photochemical stability under repeated irradiation, and can also effectively and selectively degraded a mixture of methyl orange and methylene blue. The degradation of methylene blue followed the pseudo-first-order kinetics of Langmuir-HinShelwood model. In addition, the possible mechanism of photocatalytic degradation process was proposed. [ABSTRACT FROM AUTHOR]

The incorporation of difluoromethylated (CF2) moiety into potentially useful parent molecules lead to significant changes in metabolic stability, lipophilicity, and solubility of the molecules. Over the past several years, with the advent of new difluoromethylating reagents, great progress has been made in the development of a protocol for the direct incorporation of the CF2H group into organic molecules. Among them, difluroalkylation induced by visible light has emerged as an efficient strategy over the past few years. In particular, this protocol provides a more sustainable alternative to other traditional radical‐triggered reactions in terms of environment, energy, step‐economy, health, and safety. The present review mainly focuses on the development of the photocatalytic difluoroalkylation to olefinic moiety using transition‐metal complexes, organic dyes as the photocatalyst; and some organic compounds as a medium of photocatalysis. [ABSTRACT FROM AUTHOR]

In the case of wastewater treatment, many researche's are mainly focused on nanopowder-type photocatalysts that have high efficiency because of their good dispersibility and high specific surface area. Ironically, these properties of nanopowder photocatalysts cause some drawbacks in their recovery from treated water, making practical applications in wastewater treatment difficult. The use of a three dimensional based-ceramic fiber as a substrate and graphitic carbon nitride (g-C3N4) as a visible-light-driven photocatalyst can be a promising approach to overcome the above-mentioned limitations. This study describes the immobilization of g-C3N4 on ceramic fiber using a facile co-calcination method and verifies its photodegradation activity under visible light. The recovery efficiency, physicochemical stability of samples, and the potential of the practical application of wastewater treatment were tested with organic dye decomposition experiments under visible light irradiation. [ABSTRACT FROM AUTHOR]

This very paper focuses on the preparation of an eco-friendly and efficient photocatalyst aiming to degrade organic dyes in wastewater. The cheap and abundant straws were carbonized to prepare porous carbon pieces in this study. A simple hydrothermal method was employed to prepare the porous carbon/CdS (PC/CdS) composite. CdS nanoparticles were anchored on these porous carbon sheets, forming the PC/CdS composite. The composite was annealed at 300, 400, and 600 °C, respectively, and then these samples were characterized by SEM, TEM, XRD, and FTIR. As an important parameter, the porosities of PC and the PC/CdS were characterized by BET method. Particularly, the photo-electronic response of PC/CdS has been characterized by EIS, PL, and transient photocurrent. It is found that the carrier mobility and shape of PC itself and the annealing process improved the photocatalytic activity, as well as adsorption ability. Those composites were able to thoroughly degrade RhB within 90 min under the irradiation of visible light. What is interesting and quite different from other reports is that there was no conjugated part of RhB left in the solution after photocatalytic degradation. [ABSTRACT FROM AUTHOR]

Metal–organic frameworks (MOFs) have recently emerged as a new type of prospective photocatalytic material due to their characteristics such as tunable structures, pore modification, crystalline nature with eliminated structural defects, unique semiconductor properties, etc. However, most of these systems also suffer from low activity, high cost, and low visible light utilization. Xanthene dyes are eco-friendly organic dyes used in photocatalysis. They possess the advantages of low cost, low toxicity, and high visible light response; so, they can be directly used as building blocks to fabricate MOF materials or as proper cocatalysts to increase the absorbance of irradiation leading to the construction of a reasonable photocatalytic system. Herein, we have summarized the recent developments in the study of MOFs containing xanthene dyes for photocatalytic applications. The paper can be divided into two sections depending on whether the xanthene dyes are coordinated in the MOF structure: (i) MOFs synergized with xanthene dyes for photocatalytic applications and (ii) MOFs with xanthene dyes incorporated within ligand backbones for photocatalytic applications. Moreover, in this paper, the present challenges and future opportunities in this field are also discussed. [ABSTRACT FROM AUTHOR]

In this work, H12SubPcB-Br (SubPc1) and p-hydroxybenzaldehyde were used for the synthesis of novel axially substituted subphthalocyanine H12SubPcB-OPhCHO (SubPc2). The photocatalyst hybrids TiO2/H12SubPcB-OPhCHO (TiO2/SubPc2) with different TiO2 amounts were obtained by a solvothermal method. The structure of SubPc2 was determined by single-crystal X-ray diffraction analysis and TiO2/SubPc2 was characterized by FT-IR, UV-vis, PXRD, SEM and XPS. Furthermore, the DFT and TD-DFT calculations were studied to analyze the electronic structure and optical properties of SubPc2. The photocatalytic degradation performance of all the samples was evaluated by analyzing the decomposition of methyl orange (MO), bromophenol blue (BB), methylene blue (MB) and acid magenta (AM) under visible light irradiation. It was demonstrated that SubPc2 acted in the role of sensitizer for pristine TiO2, and the optimal concentration was TiO2/SubPc2 = 25 : 1, and the calculated rate constant values were 0.68617 h−1, 1.41395 h−1, 1.00701 h−1 and 1.39237 h−1 for MO, BB, MB and AM, respectively. The enhancement of the photocatalytic performance of TiO2/SubPc2 was attributed to the extension of the photoactivity of the materials into the visible range and separation of the photogenerated electron–hole pairs. Moreover, the photocatalytic activity of the as-prepared composite was maintained at 90.11% after five cyclic stability degradation experiments, which was 4.5 times more when compared with the bare TiO2. [ABSTRACT FROM AUTHOR]