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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]

Organic dyes, which are one of the main sources of surface and groundwater pollution, cause health problems as well as environmental hazards. For this reason, ZnO, which stands out among the promising semiconductor photocatalysts in wastewater treatment due to its advantages, was preferred. In particular, Gd–Ce co-doped ZnO nanostructured films, which have been studied for the first time in the literature, were produced by ultrasonic spray pyrolysis (USP) technique and photocatalytic degradation of Methylene blue (MB) dye was carried out. Ultraviolet–Visible Spectrophotometry (UV–Vis) and Field Emission Scanning Electron Microscopy (FESEM) were used to obtain the transmittance and morphology of thin films. According to the FESEM analysis results, morphological changes in the type of nanostructure were observed after the doping. While the photocatalytic degradation percentage of the ZnO film with Gd doping was 65.84 %, when both Gd and Ce were doped, the degradation percentage increased significantly, reaching 91.58 %. Photocatalytic studies revealed that Gd–Ce co-doped ZnO films exhibited better photocatalytic efficiency compared to only Gd doped ZnO films. Therefore, when all the results are evaluated, it is concluded that ZnO:Gd:Ce photocatalysts may have a significant potential application in environmental remediation. [ABSTRACT FROM AUTHOR]

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

Cyanine derivatives are organic dyes widely used for optical imaging. However, their potential in longitudinal optoacoustic imaging and photothermal therapy remains limited due to challenges such as poor chemical stability, poor photostability, and low photothermal conversion. In this study, we present a new structural modification for cyanine dyes by introducing a strongly electron-withdrawing group (barbiturate), resulting in a new series of barbiturate-cyanine dyes (BC810, BC885, and BC1010) with suppressed fluorescence and enhanced stability. Furthermore, the introduction of BC1010 into block copolymers (PEG 114 -b-PCL 60) induces aggregation-caused quenching, further boosting the photothermal performance. The photophysical properties of nanoparticles (BC1010-NPs) include their remarkably broad absorption range from 900 to 1200 nm for optoacoustic imaging, allowing imaging applications in NIR-I and NIR-II windows. The combined effect of these strategies, including improved photostability, enhanced nonradiative relaxation, and aggregation-caused quenching, enables the detection of optoacoustic signals with high sensitivity and effective photothermal treatment of in vivo tumor models when BC1010-NPs are administered before irradiation with a 1064 nm laser. This research introduces a barbiturate-functionalized cyanine derivative with optimal properties for efficient optoacoustics-guided theranostic applications. This new compound holds significant potential for biomedical use, facilitating advancements in optoacoustic-guided diagnostic and therapeutic approaches. Barbiturate functionalized cyanine (BC1010) was developed and nanoformulated for efficient NIR-II OptA imaging of deep tumors and photothermal therapy. [Display omitted] [ABSTRACT FROM AUTHOR]

In piezoelectric catalysis, the interaction between reaction molecules and the catalyst surface is of great significance for designing highly selective reaction processes. In this study, chemically functionalized BaTiO 3 nanoparticles were fabricated using the hydrothermal method, and the piezoelectric catalytic activity was evaluated for degradation dye reactants by ultrasonic vibration. Due to surface modification of BaTiO 3 nanoparticles, the carboxyl groups will be applied on the surface of BaTiO 3 nanoparticles, resulting in the reduction in particle size and an increase in specific surface area. The adsorption of the carboxyl groups on the surface can also improve the ability of the BaTiO 3 nanoparticles to capture the organic dyes. A high piezoelectric catalytic reaction rate constant of 0.0716 min−1, together with a degradation efficiency of >90 % was achieved within 30 min under 60 kHz and 100 W ultrasonic conditions. These results show that the surface modification of BaTiO 3 nanoparticles brought excellent performance of piezoelectric catalysis by controlling the precursor and hydrothermal parameters. This study provides a new method for the preparation of chemically functionalized piezoelectric catalysts and design of other new highly selective catalysts. [ABSTRACT FROM AUTHOR]

Well-constructed photocatalysts with efficient catalytic activity have attracted much attention due to their efficient visible-light absorption and superior charge separation capability. Visible-light responsive Cu 3 Mo 2 O 9 nanoparticles are synthesized utilising a simple and environmentally friendly green combustion process with Butea monosperma leaf extract as a reducing agent. X-ray diffraction pattern confirms the formation of orthorhombic crystal structure of Cu 3 Mo 2 O 9 NPs corresponding to space group Pnma (62). Furthermore, the synthesized NPs were characterized using FTIR, UV-DRS, PL, SEM and TEM studies. It was found that the direct energy band gap was 2.29 eV. Through photodegradation in the presence of visible light, the dye-sorbed photocatalyst exhibited excellent results. The sorbents have also been examined for recycling, and it has been observed that they maintain their effectiveness even after multiple successive runs. These substances therefore appear to have potential as efficient industrial dye wastewater remediators. Moreover, the high intensity emission in the green zone is amply confirmed by the photoluminescence emission spectra and CIE coordinates. The Latent fingerprints (LFP) are visible with the application of the powder dusting process. The synthesized CMO nanoparticles exhibit ridge patterns that are well-resolved and useful for identifying unique LFP. [ABSTRACT FROM AUTHOR]

Semiconductor photocatalysts are promising for Oxygen evolution reaction (OER) and also for reducing organic pollutants in wastewater. However, their limited activity under UV light and the fast recombination of electron-hole pairs, hinder their utilization in wastewater treatment. To address these challenges a novel photocatalyst based on carbon quantum dots (CQDs) supported Zinc–Cobalt Oxide (ZnCo 2 O 4) was developed, which demonstrated enhanced photocatalytic efficiency. Experimental findings indicated that 0.7 CQDs/ZnCo 2 O 4 exhibited superior photocatalytic performance compared to ZnCO 2 O 4 and CQDs/ZnCO 2 O 4 composites materials, achieving over 100 and 96 % decomposition of methylene blue (MB) and methylene orange (MO) dyes after 50 and 140 min under UV light. The enhanced performance of 0.7 CQDs/ZnCo 2 O 4 can be attributed to the charge transfer rate and synergistic effect between the coupled CQDs and ZnCo 2 O 4. Moreover, studies with radical scavengers reveal that •O 2 , •OH, and h+ play crucial roles in the breakdown of MB and MO dyes. Furthermore, 0.7 CQDs/ZnCo 2 O 4 displayed very low overpotential of 220 mV at 100 mA cm−2 for OER activity with a robust durability for 250 h at 500 mA cm−2. • CQDs-decorated ZnCo 2 O 4 Mss was developed by facile impregnation-thermal methode. • The enhanced catalytic activity of CQDs/ZnCo 2O 4 is due to the n-p junction, which generatesholes, ●OH, and ●O 2−. • Optimized 0.70 CQDs/ZnCo 2O 4 achieves nearly100% MB degradation in 50 min. • The photocatalytic degradation mechanism of CQDs/ZnCo 2O 4 MSs enhanced charge separation and improve overall photocatalytic activity. [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]

To achieve the actual application of MoO x in absorption removal of organic dye from water, eco-friendly, facilely-scalable, high-yield, and cost-efficient synthesis of MoO x with desirable structures and superior adsorption capacities remains a great challenge. Herein, for the first time, a novel synthetic route to MoO 3 micro-/nanocrystals with different microstructures was based on mechanochemical reactions and subsequent annealing, and their inherent formation mechanisms were also discussed. Moreover, the adsorption kinetics, thermodynamics, and mechanism of Rhodamine B (RhB) on α h -MoO 3 hybrid were systematically investigated. The results show that the microstructures of MoO 3 can be controlled by facile adjusting the dosage of H 2 C 2 O 4 ·2H 2 O, which leads to the different milling precursors. The bicrystalline hybrid of α-MoO 3 nanosheets and h -MoO 3 microrods (α h -MoO 3 hybrid) exhibits an ultrahigh maximum adsorptive capacity (751.88 mg g−1) for RhB at the high initial concentration (80 mg L−1), more than 3 times enhancement compared to that of α-MoO 3 particles (210.16 mg g−1), which can be attributed to the larger specific surface area (28.77 m2 g−1) and more negative surface potential (−72.00 mV). This work provides a scalable and controllable route to synthesize MoO 3 micro-/nanocrystals with desired microstructures, contributing a promising and excellent adsorbent for the practical removal of organic dyes from water. [ABSTRACT FROM AUTHOR]

Metal-oxide nanomaterials represent a promising and inexpensive alternative to plasmonic metallic nanostructures currently used for surface-enhanced Raman scattering (SERS) spectroscopy. They profit from a chemical enhancing mechanism, i.e., charge transfer between the adsorbed molecule and the substrate. In this study, SERS-active nanostructured films based on vanadium pentoxide (V 2 O 5) are produced by the combination of gas-phase synthesis of nanoparticles followed by their thermal annealing, i.e., using a fully solvent- and linker-free procedure. The SERS performance of V 2 O 5 nanoparticle films was found to be strongly linked with porosity and the appropriate crystalline structure adjusted by annealing. A Raman spectroscopy and X-ray diffraction revealed that V 2 O 5 crystalline nanoparticles are formed only after the annealing at temperatures equal to or higher than 300 °C. Such produced V 2 O 5 nanoparticle films allow for sensitive and reproducible detection of organic dyes (methylene blue, rhodamine 6G and crystal violet), while their SERS enhancement (analytical enhancement factor close to 103) is significantly higher as compared with magnetron sputtered and annealed V 2 O 5 thin films. Our study represents an important step in designing novel plasmon-free SERS-active platforms with the aim of improving their stability and spectral reproducibility compared to other non-plasmonic and plasmonic ones. [ABSTRACT FROM AUTHOR]

Constructing heterojunction between two semiconductors is an effective way to design high performance photocatalysts. S-scheme heterojunction system with strong redox ability is fit for the photocatalytic H 2 evolution and simultaneous wastewater purification. Herein, a 2D/2D heterojunction (H 2 WO 4 /TiO 2) has been constructed between tungstic acids (H 2 WO 4) and titanium dioxide (TiO 2) nanosheets. Due to the photo-electron storage ability of H 2 WO 4 , a S-scheme heterojunction system is constructed. Meanwhile, 0D Pt nano cluster are loaded on the surface of TiO 2 , which logic underpins the formation of the S-scheme heterojunction electron pathway. Benefit from the facilitated charge transport for the direct charge path and the preserved redox ability, 0D Pt–H 2 WO 4 /TiO 2 hybrid exhibits high H 2 production activity (3440 μmol h−1 g−1) with RhB as sacrificial agent. This work provides a novel strategy to design 2D/2D S-scheme heterojunction to improve photocatalytic performance in dual functional photocatalytic H 2 production system with organic dyes as sacrificial agent. [Display omitted] • Synthesis of a 2D/2D H 2 WO 4 /TiO 2 S-scheme heterojunction is reported. • Electrons storage and strong redox ability of H 2 WO 4 /TiO 2 is reported. • High H 2 evolution reaction performance with RhB as sacrificial agent. [ABSTRACT FROM AUTHOR]

One potential method to lower the cost of electrocatalytic green hydrogen production is to use metal sulfide-based electrocatalysts in hybrid water electrolysis. This work uses a one-step hydrothermal synthesis to create copper cobalt sulphide (CuCo 2 S 4) nanosheets for hybrid water splitting. Significant water-splitting activity was achieved using urea and organic dye (methylene blue) as supporting electrolytes to avoid delayed OER kinetics. For the KOH + urea and KOH + organic dye electrolytes, the working electrode displays an overpotential of 1.37 V against RHE and 1.30 V vs RHE, respectively, to yield a current density of 10 mA/cm2. The CuCo 2 S 4 working electrode exhibits an overpotential of 212 mV versus RHE and 158 mV vs RHE at 10 mA/cm2 current density while monitoring hydrogen evolution reaction (HER) activity. For the KOH + organic dye electrolyte, the electrode exhibits exceptionally efficient electrocatalytic water splitting, with an overpotential of 1.50 V at a current density of 10 mA/cm2. At high current densities, the CuCo 2 S 4 working electrode shows exceptional stability at industry standards throughout a broad pH range of basic, acidic, neutral, and saline environments. The use of several supporting electrolytes demonstrates an overall water splitting that is energy-efficient. Wastewater treatment can be accomplished through a circular economy strategy by merging the goals of environmental remediation (dye degradation) and renewable energy production (hydrogen evolution). This approach promotes sustainable growth, reduces waste, and encourages resource recovery. According to the internationally endorsed Sustainable Development Goals (SDGs), treating wastewater has the potential to help achieve 11 of the 17 SDGs. • CuCo 2 S 4 is synthesised by hydrothermal technique for bifunctional water splitting. • CuCo 2 S 4 exhibits excellent stability in basic, acidic, neutral, and saline electrolyte. • CuCo 2 S 4 shows the bifunational water electrolysis in alkaline condition. • CuCo 2 S 4 shows advanced oxidation reaction in urea and textile dye electrolyte. [ABSTRACT FROM AUTHOR]

The development of a highly efficient catalyst for water splitting and photodegradation of organic dyes has become the focus of a considerable number of research groups. In the work described here CdZnS@MIL-53(Fe) and ZnS@MIL-53(Fe) were synthesized by the solvothermal method and subjected to thermal degradation at 520 °C in an oxidative environment to obtain CdZnS/Fe 2 O 3 and ZnS/Fe 2 O 3 , respectively. Electrocatalytic activity for the oxygen evolution reaction is analyzed via cyclic voltammetry and linear sweep voltammetry. It was found that CdZnS@MIL-53(Fe) shows maximum catalytic activity for the oxygen evolution reaction and delivers 10 mAcm−2 current density at 95 mV overpotential as compared to MIL-53(Fe)/NF (210 mV) and ZnS@MIL-53(Fe)/NF (112 mV). Similarly, the derivative of it, CdZnS/Fe 2 O 3 , shows maximum catalytic activity for the oxygen evolution reaction and delivers 10 mAcm−2 current density at 90 mV overpotential as compared to Fe 2 O 3 (204 mV) and ZnS/Fe 2 O 3 (115 mV). Based on these results, it is evident that these materials are highly efficient for OER activity compared with other materials in literature. Similarly, CdZnS/Fe 2 O 3 shows maximum photocatalytic activity for the photodegradation of Rhodamine B, up to 75% compared to CdZnS@MIL-53(Fe), which degrades up to 51% of the dye. The synthesized materials were characterized by powdered X-ray diffraction, Fourier transform infrared spectroscopy and scanning electron microscopy. Based on these results the aim is to develop more MOF-based materials and their derivatives by simple heat treatment and to implement them in different catalytic applications. [Display omitted] • Designing of highly efficient catalysts by in-situ incorporation of CdZnS nanoparticles in (MIL-53(Fe). • The newly designed CdZnS@MIL-53(Fe) and its derivative CdZnS/Fe 2 O 3 showed efficient OER activity. • The CdZnS/Fe 2 O 3 is also effective forphotodegradation of Rhodamine B (up to 75% in just 80 min). • The better catalytic activity is due to formation of heterojunction between CdZnS and MIL-53(Fe) or its derivative. [ABSTRACT FROM AUTHOR]

• The condensed phosphates effectively modified the morphology of LDHs film. • Cyclic condensed phosphates acted as enhancers for flake spacing. • Linear condensed phosphates improved flake dispersion and orientation. • The impact of cyclic phosphates on the photocatalytic performance was significant. This study presents a facile and rapid method for synthesizing novel Layered Double Hydroxide (LDH) nanoflakes, exploring their application as a photocatalyst, and investigating the influence of condensed phosphates' geometric linearity on their photocatalytic properties. Herein, the MgO film, obtained by plasma electrolysis of AZ31 Mg alloys, was modified by growing an LDH film, which was further functionalized using cyclic sodium hexametaphosphate (CP) and linear sodium tripolyphosphate (LP). CP acted as an enhancer for flake spacing within the LDH structure, while LP changed flake dispersion and orientation. Consequently, CP@LDH demonstrated exceptional efficiency in heterogeneous photocatalysis, effectively degrading organic dyes like Methylene blue (MB), Congo red (CR), and Methyl orange (MO). The unique cyclic structure of CP likely enhances surface reactions and improves the catalyst's interaction with dye molecules. Furthermore, the condensed phosphate structure contributes to a higher surface area and reactivity in CP@LDH, leading to its superior photocatalytic performance compared to LP@LDH. Specifically, LP@LDH demonstrated notable degradation efficiencies of 93.02%, 92.89%, and 88.81% for MB, MO, and CR respectively, over a 40 min duration. The highest degradation efficiencies were observed in the case of the CP@LDH sample, reporting 99.99% for MB, 98.88% for CR, and 99.70% for MO. This underscores the potential of CP@LDH as a highly effective photocatalyst for organic dye degradation, offering promising prospects for environmental remediation and water detoxification applications. [ABSTRACT FROM AUTHOR]

The development of simple coumarin-based organic dyes loaded over TiO 2 is found to possess great potential for efficient photocatalytic hydrogen generation. Herein, we studied a series of coumarin-based organic dyes, namely, 4-(naphthalene-1-yl)-2-oxo-2H-benzo[h]chromene-3-carbonitrile loaded over Pt–TiO 2 is referred to as TC-2. The electronic as well as structural properties of the dyes were visualized experimentally and theoretically with the modification of the structural chromophoric groups over the meso-position of the coumarin dyes and revealed that the meso-substitution of the naphthalene ring over the TC-2 resulted in the decrease in electron-hole recombination dynamics. TC-2 photocatalyst depicted enhanced activity of (H 2 rate-5.54 mmolg−1h−1) under neutral pH (AQY-14.5%, TON-5970), which is majorly obtained due to the increased conjugation of the naphthalene ring which thereby increases the light-sorption capacity of the materials in comparison to that of the others, synthesized materials in presence of TEOA. The extended π-π∗ conjugation in the substituent modification and the cyano groups over the simple coumarin groups leads to enhanced activity. This work paves the way towards sustainable development of dye-sensitized photocatalysts for green fuel generation. • Small molecule coumarin dyes were reported in photocatalytic H 2 generation. • The effect of substituent, cyano-functional group on HER has been investigated. • Dye-TiO 2 (TC-2) exhibited H 2 rate 5.54 mmol.g−1h−1 under neutral pH (AQY-14.5%, TON-5970). • The lifetime decay study revealed long lifetime of the TC-2, with 7.73 ns established superior HER. • DFT studies reveal better overlap and charge separation in photocatalyst. [ABSTRACT FROM AUTHOR]

The preparation of high performance, low cost and recyclable adsorbents is very important to cope with the increasingly devastating water pollution. As a typical three-dimensional porous carbon material, carbon foam (CF) is expected to be a highly efficient adsorbent to wipe out organic dyes from wastewater. However, the uneven size distribution, and lack of adsorption sites signified by insufficient foaming process limit its wider application in the environmental field. Here, CF/carbon nanotubes/graphene oxide (CF/CNTs/GO) composites (adsorbents) were prepared by press-assisted foaming and carbonization methods using mesophase precursors of coal tar pitch and CNTs followed by impregnation of GO nanosheets. The results highlighted that the addition of CNTs facilitated improvement in pore distribution, porosities, and mechanical properties (20 MPa). After treating with GO nanosheets, the adsorption performances of CF/CNTs/GO adsorbents substantially improved due to the increased active sites in the CF/CNTs and the adsorption rate and capacity of methylene blue (MB) reached 73.1% and 146 mg/g respectively. Further, adsorption isotherms (Langmuir and Freundlich), thermodynamics, quasi-first order and quasi-second order kinetics and intraparticle diffusion models were employed to investigate the adsorption mechanism. This work provides a low-cost fabrication technique for the high-performance CF/CNTs/GO adsorbent and is expected to provide reference for application in the treatment of contaminated water. [ABSTRACT FROM AUTHOR]

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

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

The construction of ternary TiO 2 NTs/Ag 3 PO 4 –AgBr photocatalysts was carried out by the SILAR deposition of Ag 3 PO 4 and AgBr on TiO 2 nanotube arrays (TiO 2 NTs) for enhancing the photocatalytic application in H 2 evolution and dyeing wastewater remediation. The adjustment of Ag 3 PO 4 /AgBr deposition cycles was used to optimize the optical absorption and photocatalytic property. The TiO 2 NTs/Ag 3 PO 4 –AgBr (5) prepared with 5 cycle deposition of Ag 3 PO 4 and AgBr exhibited the optimal photoelectric activity and photocatalytic performances. The photocatalytic rate constants for the degradation of MO, RhB and MB dyes achieved 1.35 × 10−2, 3.30 × 10−2 and 4.47 × 10−2 min−1, respectively, and the visible light-driven photocatalytic H 2 evolution rate achieves 46.87 μmol cm−2 h−1. •O 2 − radicals exhibited the key influence on the organic dye degradation, and the as-prepared photocatalysts showed exceedingly high photocatalytic activity and stability. Furthermore, the photocatalytic mechanism was proposed based on the ESR result. [ABSTRACT FROM AUTHOR]

[Display omitted] A nanocomposite based on graphene oxide and cobalt trimesinate was obtained by in situ method and employed in solid-phase extraction of organic pollutants using the triphenylmethane dye, brilliant green, as an example. The maximum adsorption reaches 385.2 mg g–1. [ABSTRACT FROM AUTHOR]

Wastewater remediation is a major issue that threatens the ecosystem and health of human population and hence deserves our undivided attention. Dye effluents, in particular those comprising organic colourants from a number of industrial sites, are a major source of wastewater pollution that poses serious dangers to human health and the environment today. Therefore, the goal of this study is to eliminate these coloured effluents, which are present in substantial amounts in wastewater, either singly or in mixtures. In this respect, we present an easy sol-gel synthesis of CoFe 2- x Cr x O 4 (x = 0, 0.2, 0.4, 0.6, 0.8, and 1) nano-ferrites for use as efficient photocatalysts. P-XRD technique was used for the confirmation of cubic spinel nanostructures having crystallite sizes in the nano-regime. Also, the optical band gap values resulted from Tauc plot indicates that incorporation of Cr3+ significantly reduces the band gap values. All the Co–Cr nano photocatalysts can be easily separable using an external magnet as indicated by the magnetic studies. For exploring the photocatalytic activity by photo-fenton process, we chose Rhodamine-B (RhB) as a model dye pollutant. Surprisingly, Cr3+ substitution into cobalt ferrite resulted in a dramatic transformation of the inert CoFe 2 O 4 into a highly visible light active photocatalyst for organic pollutant degradation. The CoFeCrO 4 nanocatalyst showed excellent results for the removal of RhB i.e., 99% removal in 30 min as compared to the CoFe 2 O 4 which was found to be inactive for the degradation. As a result of these exciting photocatalytic results, we were further encouraged to extend the degradation of a few other organic dye contaminants such methylene blue (MB), methyl orange (MO) and the mixture all three dyes (RhB + MB + MO). It was found that CoFeCrO 4 photocatalyst efficiently and swiftly degrades all three dye contaminants individually or in mixture with excellent recyclability and durability. [ABSTRACT FROM AUTHOR]

Significant ecosystem damage and severe environmental issues have surfaced due to unplanned exploitation of resources and industrial expansion. The water bodies are continuously polluted by numerous organic dyes released from industrial effluents. In this work, we report construction of new g-C 3 N 5 /Bi 24 O 31 Br 10 S-scheme heterojunction for UV–visible light driven superior organic dye degradation. The integrated heterojunction with high interfacial charge transfer exhibited excellent 99.08% (∼100%) within 60 min exposure which is manifolds higher than bare g-C 3 N 5 and Bi 24 O 31 Br 10. The mechanistic investigations showed that the key active radicals in photocatalytic CV degradation are the •O 2 - and h+. Building an S-scheme model with favourable energy band structure encourages efficient separation of charges while maintaining the inherent redox capacity of the g-C 3 N 5 /Bi 24 O 31 Br 10 catalyst, which is highly beneficial for superior photocatalytic performance. This work offers a fresh viewpoint for creating organic-inorganic hybrid new S-scheme heterojunctions for high performance photocatalytic waste-water treatment. • High efficiency 2D–2D g-C 3 N 5 /Bi 24 O 31 Br 10 S-scheme heterojunction was designed. • Catalyst exhibit excellent degradation efficiency of 99.08% for CV removal. • PL suggests the efficient charge separation of the carriers. • ·O 2 - and h+ are responsible for CV degradation. [ABSTRACT FROM AUTHOR]

Degradation of water quality caused by organic dyes discharge is a great concern owing to their high toxicity and bioaccumulative nature. A new three-dimensional cellulose/titanium/graphene oxide (3D-CTG) system was fabricated via an ecofriendly ice-segregation method for sequestrating malachite green (MG) and crystal violet (CV) dyes in polluted water. The designed graphene oxide-based system was validated by several analytical techniques, with the results indicating the formation of lamellar porous networks and abundant chemical functional groups. The adsorption of the dyes was modeled by response surface methodology whereby 4 parameters (dosage, initial concentration, temperature and contact time) were optimized to achieve the highest CV removal (94.29%) at 10 mg of adsorbent dosage, 70 mg/L of initial CV concentration, 30 °C and 45 min, and the highest MG removal (81.07%) at 12.5 mg of dosage, 40 mg/L of initial MG concentration, 40 °C and 31 min. The saturated 3D-CTG adsorbent was recyclable as supported by 41.1 – 71.7% regeneration efficiencies after the fourth cycle of usage. The Langmuir maximum adsorption capacities of CV (583.6 mg/g) and MG (334.8 mg/g) dyes were comparable to the literature data which reflected the superior adsorption performance and high applicability of the new 3D-CTG system in the decontamination of organic dyes wastewater. [Display omitted] • Design and optimization of 3D-CTG adsorbent for efficient CV and MG dye removals. • Impressive adsorption capacities of 583.6 mg/g for CV and 334.8 mg/g for MG. • Highest 94.29% CV removal at optimized 10 mg dose, 70 mg/L, 30 °C and 45 min. • Optimized state for 81.07% MG removal at 12.5 mg dose, 40 mg/L, 40 °C and 31 min. • High regeneration efficiencies of 41.1–71.7% using 0.01 mol/L HCl eluent. [ABSTRACT FROM AUTHOR]

Designing high-performance ceramic adsorbent with a wide spectrum of properties such as regulatable pore structure, high surface area, ultrahigh organic dye removal efficiency and renewability in an affordable and rational approach is vital for real-life applications. However, integrating all these individual functionalities simultaneously into one bulky material is still challenging. Herein, hierarchical porous ceramic adsorbents with nanofibrous-granular composite structure were proposed via colloidal co-assembly of coal-containing kaolin waste and silicon to resolve the above conflicting demands. Such structure endows the resultant products with satisfactory surface area of 52 m2 g−1, ultrahigh malachite green removal efficiency of 97.6%, outstanding adsorption capacity of 97.6 mg/g, excellent renewability after calcining at 500 °C. Such ceramic adsorbent provides a sustainable and feasible strategy for fabricating water purification materials. [ABSTRACT FROM AUTHOR]

The versatile process of photo-catalysis is used to treat water pollution and other environmental issues. Another way for solving environmental pollution remediation is metal ferrite with a spinel structure, which is widely used as a photocatalyst. In this work, the fabrication of all the materials was followed by using the co-precipitation method, while graphene oxide was prepared by hummer's method. Synthesized samples were characterized by using various techniques like XRD, SEM, UV–visible and FT-IR. For the identification of functional groups FT-IR was used. Surface morphology was determined by SEM. The band gap was calculated with the help of the Tauc plot. Methyl orange, crystal violet (as coloured dyes), and benzoic acid (as colourless effluent) were chosen to evaluate the photocatalytic performance of fabricated samples. The photocatalytic degradation (%) of composite is higher than heterojunction and pristine Magnesium ferrite and Zinc oxide. In the case of methyl orange, the degradation percentage was 80% by the composite (MgFe 2 O 4 -ZnO-GO, MF/ZO/GO) while 78% by heterojunction (MgFe 2 O 4 -ZnO, MF/ZO), 74% by ZnO (ZO) and 65% by MgFe 2 O 4 (MF). Further, crystal violet showed % a degradation 80% by composite and 72% by heterojunction, 74% by MgFe 2 O 4 (MF) and 65% by ZnO (ZO). Similarly, MF, ZO, MF/ZO and MF/ZO/GO showed 36%, 39%, 43% and 45% for benzoic acid, respectively. For the degradation of pollutants, the synthesized material will attract the attention of the researcher. [ABSTRACT FROM AUTHOR]

The energy crisis and environmental pollution have been increasing day by day due to the high consumption of nonrenewable energy which insists researchers discover alternative methods to harvest energy from waste materials and resources. This work reports the construction of the energy harvesting device using a purely natural α-hematite incorporated PVDF membrane. Doping of purely natural α-hematite led to the growth of polarization forming the β-phase high which has been confirmed by FTIR and other theoretical methods (DFT). The structure morphology has been characterized by using basic characterization tools i. e XRD, SEM, EDAX, and TEM. The augmentation of the polarization has been established by the increased value of the dielectric constant. Herein, we have fabricated the device using PVF5 membrane that can develop voltage 42V, power 1328 μW/cm3 by finger tapping, and the device can also harvest energy even from the water flow from several sources and falling from different heights. Water pollution is another big concern in today's world along with the energy crisis. Piezocatalysis is one of the best-emerging technologies for the treatment of water pollution and this method has been employed in our study by using PVF5 membrane to degrade organic dye i. e RhB dye. 86% degradation of the dye in 40 min has been achieved due to the formation of several oxidative spices (ROS) like as •O−, •OH, e−, h+, etc. Using ultrasound-assisted piezocatalysis method, and even after repetitive use of it the efficiency does not reduce significantly. Henceforth this article reports the multifunctional purely natural α-hematite mediated membrane that can concomitantly harvest energy from mechanical as well as decontaminate water by degradation of organic pollutants from water. [ABSTRACT FROM AUTHOR]

After amorphous Ce(IO 3) 4 powder was prepared using precipitation method at room temperature, powder samples of crystalline Ce(IO 3) 3 , α-La(IO 3) 3 and δ-La(IO 3) 3 were prepared by calcining the precipitates formed by mixing the solutions. All samples eluted some constituent ions in the solution. The Ce(IO 3) 4 decomposed methylene blue and methyl orange in water in the dark. The valence of Ce measured before and after the decomposition reaction suggested oxidative decomposition by Ce(IV). These samples exhibited high antibacterial activity against Escherichia coli and Staphylococcus aureus , and also high antiviral activity against the non-enveloped virus bacteriophage Qβ and the enveloped virus bacteriophage Φ6. Moreover, these samples caused protein denaturation. It is conceivable that the adsorption of lanthanum and cerium ions leaked from the sample, the oxidation power of ions such as Ce(IV) and IO 3 −, and pH value affected these antibacterial and antiviral activities. [ABSTRACT FROM AUTHOR]

[Display omitted] Two novel aromatic compounds containing thieno[2',3':4,5]-thieno[3,2- b ]thieno[2' ' , 3' ':4' ,5']thieno[2',3':4,5]-pyrrolo[3,2-g]indole as the electron-donating center and terminal 3-(dicyanomethylene)indan-1-one (or 5,6-difluoro analogue) electron-accepting groups exhibit efficient light absorption in the red and near-infrared spectral regions, have low levels of the highest occupied molecular orbital (up to –5.65 eV) and lowest unoccupied molecular orbital (–3.91 eV) and a relatively low band gap value (up to 1.74 eV). The optical, thermal and structural properties are explored and compared with those of their closest and well known analogues, Y5 and Y6. [ABSTRACT FROM AUTHOR]

Monitoring the contents of organic dyes in real-time is crucial for the valuation of photocatalyst performance. To achieve this, a method of detecting organic dyes was designed based on color variations by using Ag nanoparticle modified TiO 2 nanotubes (Ag/TiO 2) as photocatalysts. The obtained Ag/TiO 2 photocatalyst possesses strong visible-light absorption, and 1.0% Ag/TiO 2 exhibited the best performance under UV and simulated sunlight. The investigation indicates that the photocatalytic activity of TiO 2 nanotubes is greatly improved by the modification with silver. Moreover, the photodegradation intermediates and pathways are demonstrated by trapping experiments and density functional theory calculations. To quantitatively determine the concentration of methyl orange, a partial least squares model was built using RGB values and the concentration of a methyl orange solution. This finding provides a new idea to fabricate a sensor for point-of-care test of organic dyes in the field of environmental applications. [ABSTRACT FROM AUTHOR]

In this work, α-MnO 2 /BiVO 4 nanocomposites with varying MnO 2 contents (0–7 wt%) were successfully prepared via the simple chemical method. The structure, morphology, and optical properties of prepared nanocomposites were studied by various analytical techniques including X-ray diffraction (XRD), scanning electron microscopy (SEM), UV–visible absorption spectroscopy, and photoluminescence (PL) spectroscopy. The photocatalytic efficiency of α-MnO 2 /BiVO 4 nanocomposites was studied via decomposition of rhodamine B (RhB) and tetracycline (TC) under exposure to visible light (λ ≥ 420 nm). Due to good structure and composite advantages, 5%MnO 2 /BiVO 4 (MnBV-5) photocatalyst exhibited superior RhB and TC degradation efficiency to all other samples. In addition, the MnBV-5 photocatalyst showed good stability, and no apparent reduction in photocatalysis efficiency was noted after five testing cycles. Therefore, the MnO 2 /BiVO 4 nanocomposite demonstrated a good potential for photocatalytic decomposition of new water contaminants. [ABSTRACT FROM AUTHOR]

Zinc oxide−doped titanium dioxide/graphene aerogel (ZnO−TiO 2 /GA) nanocomposite was fabricated by the two-step solvothermal method for efficient removal of dyes and toxic metals in aqueous media. Based on the results, ZnO−TiO 2 /GA material with an optimal ZnO amount of 300 mg has a synergistic effect on exhibiting an excellent photocatalytic-adsorption capacity. The highest degradation efficiency for methylene blue, rhodamine B, and methyl orange was 99.7, 97.3, and 94.9%, respectively, with the optimum conditions: catalyst dose of 0.2 g L−1, 20 ppm dye concentration at 20 min under ultra-visible (UV−11 W) light irradiation. Moreover, the material also showed outstanding reusability with more than 90% dye removal efficiency after 8 cycles of testing. The proposed pathway and intermediate products of dye degradation were also investigated using liquid chromatography−mass spectrometry (LC−MS) analysis. Besides that, the maximum absorption capacity for the toxic metal ions Cd2+ and Co2+ are 380.6 and 230.1 mg g−1, respectively, which followed by the Langmuir isotherm adsorption model. The results exhibited the material's potential for the treatment of water containing toxic metals and waste from textile dyeing. [Display omitted] [ABSTRACT FROM AUTHOR]

Photocatalytic degradation by visible light-driven generation of reactive oxygen species shows great promise for purification of environmental water. However, such degradation is limited by the low separation efficiency of photogenerated carriers and the poor adsorption capacity of the photocatalyst itself. To solve these problems, we successfully constructed and prepared a composite hydrogel (BV-GH) combining a three-dimensional network structure composed of graphene oxide and BiVO 4 to achieve the synergistic effects of adsorption enrichment and photocatalytic degradation. The results show that the amount of methylene blue and methyl orange adsorbed by BV-GH is 258.78 mg g−1 and 217.16 mg g−1, respectively, which is much higher than that obtained for pure BiVO 4. Due to the synergistic effect of adsorption enrichment and photocatalytic degradation, the degradation rate of the dye by BV-GH reaches 94.18% in 60 min, which is 6.98 times higher than that obtained for pure BiVO 4. Electron spin-resonance (ESR) experiments confirm that the main factor affecting the dye degradation by BV-GH is the ability to produce more ·OH and ·O 2 −, which is an important reason for the excellent antibacterial performance of BV-GH against E. coli. This work can provide further inspiration for photocatalytic technology in water purification. • BiVO 4 /GO hydrogel exhibits high adsorption properties for both anionic (MO) and cationic dyes (MB). • The BV-GH 2 hydrogel have better degradation efficiency for organic dyes than pure BiVO 4 (∼6.98 times). • The production of more reactive oxygen species allows the composite hydrogel to have even better antibacterial properties. • BiVO 4 /GO hydrogel shows high photocatalytic activities combined with adsorption-enrichment. [ABSTRACT FROM AUTHOR]

Water shortage is a global challenge due to increased demand and hence, reliable wastewater treatment avenues must be created to solve this problem. In this work, we report about the fabrication of dual performance polyethersulfone (PES) membranes modified with molybdenum disulfide (MoS 2) nanosheets of different phases for wastewater remediation. We optimised process parameters to obtain large area, defect free membrane sheets. Comprehensive characterization revealed the phase disparity of MoS 2, and changes introduced in the modified PES membranes. Blending MoS 2 with PES membranes enhanced the mechanical properties as well as water uptake differently. The optimum PES membrane was modified with 0.2 wt% of 70% 1 T/2 H MoS 2 and possessed superior pure water permeance of 778 kg/m2.h.bar. It also showed superior performance towards oil removal with rejection efficiency of 99% for 1 g/L oil concentration and it revealed excellent antifouling properties. The optimum membrane showed appreciable performance in organic dye rejection, even though it was outpaced by the 0.5 wt% of 70% 1 T/2 H MoS 2 modified PES with a dye rejection of 98% towards methylene blue and 92% towards Rhodamine B. This work revealed that the phase of MoS 2 strongly influences the structure and performance of the resultant PES-based nanocomposite membranes in ultrafiltration applications. [Display omitted] [ABSTRACT FROM AUTHOR]

It has been always attractive to design a sustainable bio-derived adsorbent based on industrial waste lignin for removing organic dyes from water. However, existing adsorbent strategies often lead to the difficulties in adsorbent separation and recycling. Herein, we report a novel magnetically recyclable bio-adsorbent of Mg(OH) 2 /Fe 3 O 4 /PEI functionalized enzymatic lignin (EL) composite (EL-PEI@Fe 3 O 4 -Mg) for removing Congo red (CR) by Mannish reaction and hydrolysis-precipitation. The Mg(OH) 2 and PEI functionalized EL on the surface act as active sites for the removal of CR, while the Fe 3 O 4 allows for the easy separation under the help of a magnet. As-obtained EL-PEI@Fe 3 O 4 -Mg forms flower-like spheres and has a relatively lager surface area of 24.8 m2 g−1 which is 6 times that of EL. The EL-PEI@Fe 3 O 4 -Mg exhibits a relatively high CR adsorption capacity of 74.7 mg g−1 which is 15 times that of EL when initial concentration is around 100 mg L−1. And it can be easily separated from water by applying an external magnetic field. Moreover, EL-PEI@Fe 3 O 4 -Mg shows an excellent anti-interference capability according to the results of pH values and salt ions influences. Importantly, EL-PEI@Fe 3 O 4 -Mg possesses a good reusability and a removal efficiency of 92 % for CR remains after five consecutive cycles. It is illustrated that electrostatic attraction, π-π interaction and hydrogen binding are primary mechanisms for the removal of CR onto EL-PEI@Fe 3 O 4 -Mg. This work provides a novel sustainable strategy for the development of highly efficient, easy separable, recyclability bio-derived adsorbents for removing organic dyes, boosting the efficient utilization of industrial waste lignin. A novel lignin-based bio-adsorbent with easy separability, recyclability, excellent anti-interference, and regeneration capabilities for efficient removal of Congo red was successfully prepared. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] The interfacial solar desalination has been considered a promising method to address the worldwide water crisis without sophisticated infrastructures and additional energy consumption. Although various advanced solar evaporators have been developed, their practical applications are still restricted by the unsustainable materials and the difficulty of precise customization for structure to escort high solar-thermal efficiency. To address these issues, we employed two kinds of naturally occurring molecules, tannic acid and iron (III), to construct a low-cost, highly efficient and durable interfacial solar evaporator by three-dimensional (3D) printing. Based on a rational structural design, a robust and 3D-printed evaporator with conical array surface structure was developed, which could promote the light harvesting capacity significantly via the multiple reflections and anti-reflection effects on the surface. By optimizing the height of the conical arrays, the 3D-printed evaporator with tall-cone structure could achieve a high evaporation rate of 1.96 kg m–2 h−1 under one sun illumination, with a photothermal conversion efficiency of 94.4%. Moreover, this evaporator was also proved to possess excellent desalination performance, recycle stability, anti-salt property, underwater oil resistance, as well as adsorption capacity of organic dye contaminants for multipurpose water purification applications. It was believed that this study could provide a new strategy to fabricate low-cost, structural regulated solar evaporators for alleviating the dilemma of global water scarcity using abundant naturally occurring building blocks. [ABSTRACT FROM AUTHOR]

Transparent mesoporous TiO 2 films with enhanced photocatalytic degradation efficiency were systematically synthesized. The films were prepared using a mixed sol containing a cellulose nanocrystal (CNC) template that was spin-coated onto an ITO substrate, followed by calcination at 400 °C for 1 h. Subsequently, the fabricated films were subjected to hydrothermal treatment in a pure aqueous medium for various periods of time (1, 2, and 4 h) and at different temperatures (150 and 250 °C). The surface area and crystallite size of the prepared TiO 2 film were increased and decreased from 76.7 m2/g and 12.78 nm (without the template) to 127.3 m2/g and 9.95 nm (with the template), and then to 233.4 m2/g and 4.43 nm (1 h and 150 °C) with hydrothermal treatment, respectively. Hydrothermal treatment plays an important role in enlarging the surface area, and decreasing the crystallite size. Furthermore, the optimized TiO 2 film exhibits exceptional photodegradation activity towards organic dyes with performance nearly equal to that of the standard photocatalyst. Because of the exceptional properties of the prepared optimized TiO 2 film, the adsorption of organic dyes on its surface increases, which promotes the photocatalytic degradation efficiency during light irradiation. [ABSTRACT FROM AUTHOR]

In the present study, Fe 3 O 4 nanoparticles (NPs) supported MoS 2 nanoflowers (Fe 3 O 4 –MoS 2) are prepared by a simple and eco-friendly hydrothermal method and are well-characterized for their structure, morphology, size, phase composition, and magnetic property using XRD, FT‐IR, SEM, EDX, HR-TEM, SEM-elemental mapping and VSM techniques. As prepared Fe 3 O 4 –MoS 2 showed good catalytic activity for the reduction of p -nitrophenol (p -NP), methylene blue (MB), and methyl orange (MO) dyes in the presence of NaBH 4 in 10 min, 2 min, and 2 min with rate constants of 0.15 min − 1 , 0.88 min − 1 and 0.53 min − 1 respectively. Moreover, the Fe 3 O 4 –MoS 2 catalyst was recovered magnetically in good yield and the recovered catalyst also showed a similar catalytic efficacy even up to nine cycles. Further, cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) measurements for Fe 3 O 4 –MoS 2 electrode were performed in 1 M KOH aqueous electrolytes with (+0.50, −0.73 V) and (+0.10, −0.68 V) oxidation and reduction peaks in the reversible redox process respectively. The electrode exhibited a specific capacitance of 1.42 F g−1 basic electrolyte. EIS measurements showed a reduction in the charge transfer resistance. Modified carbon paste electrode using Fe 3 O 4 –MoS 2 is used as a sensor for the detection of paracetamol (PCM), ascorbic acid (AA), hydrogen peroxide (HP), and tetracycline (TC) pharmaceutical samples, which showed well-separated peaks. These results indicate that the prepared Fe 3 O 4 –MoS 2 has great potential to be developed as a catalyst and electrochemical sensor material for industrial applications. [ABSTRACT FROM AUTHOR]

The widespread use of organic dyes in industrial applications consistently endangers the eco-system health. The photocatalytic degradation of organic wastewater has been recognized as a highly promising strategy for combating this environmental issue. Herein, A series of bimetallic Co2+Cr3+LDH anchored AgCl as excellent solar-light-responsive Ag-decorated staggered nano-heterojunctions were constructed using a facile sono-precipitation method and their performance toward degradation of various azo dyes were investigated. Ag-AgCl-CoCrLDH(3:1)-PU exhibited excellent photocatalytic activity by degrading acid orange 7, eosin Y, rhodamine B, methylene blue, and methyl orange with respective efficiencies of 100.0 %, 98.4 %, 94.0 %, 88.7 %, and 86.2 %. The photocatalyst characteristics were determined using XRD, FESEM, TEM, EDX, BET-BJH, FTIR, and UV–vis DRS techniques. The DRS analysis of Ag-AgCl-CoCrLDH(3:1)-PU photocatalyst (E g = 2.37 eV) revealed that the introducing of LDH in the heterostructure, along with the SPR effect of Ag particles, increased the visible light absorption capacity. Furthermore, the staggered band gap accelerated charge carrier transformation, resulting in a lower recombination rate. Based on the BET-BJH results, integration of LDH combined with ultrasound irradiation increased the S BET and pore volume (V p) to 19.5 m2/g and 0.052 cm3/g, respectively (compared to bare Ag-AgCl-PU with S BET and V p of 3.4 m2/g and 0.004 cm3/g, and non-sonicated Ag-AgCl-CoCrLDH(3:1)-P with S BET and V p of 16.8 m2/g and 0.016 cm3/g). The FESEM and TEM images clearly displayed the significant influence of sonication on well dispersion and de-agglomeration of nanoparticles. Subsequently, the reusability of nanophotocatalyst was examined, and a possible degradation mechanism was suggested. [Display omitted] [ABSTRACT FROM AUTHOR]

This study has been endeavoured to investigate the potential of magnetically separable CoFe 2 O 4 –ZnO hybrid nanostructures towards the complete mineralization of organic pollutants. Facile co-precipitation method was performed to obtain CoFe 2 O 4 –ZnO nanostructures, which were well characterized. The structure, composition and morphology of the materials were confirmed via XRD, Raman, FESEM, TEM and HRTEM which revealed the successful formation of CoFe 2 O 4 –ZnO heterojunctions with particle-like morphology having size in range of 10.4–27.6 nm. The optical properties were studied using PL and DRS whereas UV–visible spectroscopy was utilized for examining photocatalytic performance. The photodegradation property of the prepared nanophotocatalysts was assessed by the decomposition of organic dyes and results showed that CoFe 2 O 4 –ZnO nanostructures exhibit highly enhanced performance over pristine CoFe 2 O 4 due to the high light utilization ability and heterojunction formation which delays the charge carrier recombination and improves the photodecomposition capability. Additionally, the novel photocatalyst recycled well up to four consecutive degradation cycles and photocatalytic mechanism supported by scavenger experiments was also proposed. This study provides sunlight responsive magnetically separable CoFe 2 O 4 –ZnO photocatalyst which efficiently achieves the goal of rapid purification wastewater. [ABSTRACT FROM AUTHOR]

Based on the structure related to the high-temperature superconductor yttrium-barium-copper oxide, two novel high-efficiency visible light photocatalysts were created in this study. The yttrium-barium oxide (YBO) semiconductors Y 2 Ba 3 O 6 (YB3O) and Y 2 Ba 4 O 7 (YB4O) were prepared by a copper-free solid-phase sintering method. They were applied for the effective treatment of dye-containing wastewater by photocatalysis under visible light irradiation. The degradation efficiency of methylene blue (MB) reached more than 95% within 10 min. Stable visible light degradation of methyl orange (MO) was achieved in the presence of YB3O and YB4O. The electron spin resonance technique and active substance capture technique confirmed the presence of superoxide radicals (·O 2 −), hydroxyl radicals (·OH) and holes (h VB +) under visible light illumination. UV–Vis diffuse reflectance spectroscopy analysis showed that the direct optical band gaps of YB3O and YB4O were 2.550 eV and 2.583 eV, respectively, which resulted in their high visible absorption at 486.27 nm and 480.06 nm. After five cycles, the recoveries of YB3O and YB4O reached 67.15% and 72.98%. Therefore, YB3O and YB4O are considered as powerful semiconductor catalysts for the photocatalytic degradation of organic dyes in wastewater. • Synthesis of yttrium -barium oxide (YBO) visible light catalyst. • Y 2 Ba 3 O 6 (YB3O) and Y 2 Ba 4 O 7 (YB4O) show a forbidden band width of 2.550 eV and 2.583 eV respectively. • The effective degradation of methylene blue was achieved within 10 min under visible light. • The mineralization of the total organic carbon in the degraded solutions of both dyes reached close to 80%. [ABSTRACT FROM AUTHOR]

Herein, we report the sunlight driven photocatalytic degradation of toxic organic dye, Rhodamine B using α-Bi 2 O 3 nanosheets as an effective photocatalyst. The α-Bi 2 O 3 nanosheets were prepared by simple annealing assisted thermal decomposition method and characterized by several techniques in order to understand its morphological, compositional, structural and optical properties. Morphological, structural and compositional investigations confirmed the formation of sheet-like morphologies, high-crystalline monoclinic crystal structure, and pure α-Bi 2 O 3 , respectively. The synthesized α-Bi 2 O 3 nanosheets exhibited a high photocatalytic degradation of a toxic organic dye, i.e. Rhodamine B (RhB). Under optimal reaction conditions, ∼95% photocatalytic degradation of RhB (10 mg/L, pH 10) was observed in 180 min using 0.75 g/L catalyst dosage under sunlight irradiation. According to the findings, the synthesized catalyst had outstanding photocatalytic properties and can be used to cleanse textile wastewater under direct sunlight. [ABSTRACT FROM AUTHOR]

Ag/AgCl/3D-rGO is facilely synthesized by a mild method, and the resulting composite catalyst is systematically characterized by means of Scanning Electron Microscope, Energy Dispersive Spectrometer, Raman Spectra, X-Ray Photoelectron Spectroscopy and X-Ray Diffraction. The characterization result shows that Ag/AgCl nanoparticles are homogeneously dispersed throughout the sheet surface of the block graphene oxide. The catalytic activity of the resulting composite is assessed by the degradation of Methyl Orange (MO) and Rhodamine B (RhB) in the presence of sodium borohydride. The pseudo-first order kinetic study shows that Ag/AgCl/3D-rGO possesses outstanding catalytic degradation activity toward both MO and RhB. The degradation rates of MO and RhB can reach 92 % and 98 % in 15 min, respectively, indicating the rapid catalytic performance of the resulting Ag/AgCl/3D-rGO in the presence of sodium borohydride. In addition, the possible formation and dyes degradation mechanism of Ag/AgCl/3D-rGO are also proposed. The excellent catalytic activity reveals that Ag/AgCl/3D-rGO may have a promising potential application in organic dye wastewater treatment. [Display omitted] • Ag/AgCl/3D-rGO composites are facilely fabricated by a mild method. • Ag/AgCl is in-situ loaded on the surface of 3D-rGO with uniform distribution. • Ag/AgCl/3D-rGO has rapid high catalytic activity towards degradation of MO and RhB. [ABSTRACT FROM AUTHOR]

In this paper, we present a new catalyst based on graphene oxide deposited on PES fabric and decorated with Cu0 and Ag0 NPs. The material was created via dip-coating followed by in-situ reduction of Cu2+ and Ag+ to Cu0 and Ag0 on its surface. Different physico-chemical characterizations were performed to investigate the possible interfacial interactions between PES, GO, and metallic ions. The PES-GO/Cu0-Ag0 was evaluated for the reduction of 4-nitrophenol (0.03. 10-3 M), Rhodamine B (20 ppm) and Methyl Orange (20 ppm). The PES-GO/Cu0-Ag0 catalyst shows outstanding catalytic activity for the reduction of all organic compounds tested. The reaction constant for 4-NP, RhB, and MO was 0.564, 0.569, and 0.42 min-1, respectively. Furthermore, the findings indicate that PES-GO/Cu0-Ag0 coatings on PES substrate may be advantageous to avoid problems with powder separation. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • Functional DESs-PANI@Fe 3 O 4 nanosphere adsorbents were prepared by surface grafting technique. • The grafting of DESs greatly improved the adsorption capacity for organic dyes. • ChCl-Lac-PANI@Fe 3 O 4 can achieve extremely high adsorption capacity and high removal rate in a few minutes. • The adsorption effect of ChCl-Lac-PANI@Fe 3 O 4 is still excellent after several cycles. • The microscopic mechanism of ChCl-Lac-PANI@Fe 3 O 4 adsorption process was explained by DFT calculation and chemical changes after adsorption. Dyes are organic compounds that are necessary to impart color to substrates. Because methyl orange (MO) and methylene blue (MB) are difficult for the environment to biodegrade, it is critical that dyes be recycled quickly and efficiently. Herein, oxidation was used to create polyaniline@Fe 3 O 4 nanorods (PANI@Fe 3 O 4). Then, different types of deep eutectic solvents (DESs) were grafted to prepare several novel adsorption materials for green DESs-based magnetic nanomicrospheres (DESs-PANI@Fe 3 O 4). The grafting of DESs not only increased the BET surface area (65.24 m2/g) of the adsorbent, provide a channel for rapid adsorption and efficient mass transfer of pollutants, but also provided abundant functionalized active sites (O-H, C = O, NH+) for efficient dye removal. Comparison of FTIR and XPS spectra before and after adsorption showed that specific functional groups (–OH, –NH 2 , –COOH) and functional chemical bonds (N-H, C-O, O-H) played an important role in rapid and effective dye removal. When grafted with ChCl-Lac as a green solvent, the adsorption capacity of the resulting ChCl-Lac-PANI@Fe 3 O 4 for MO and MB dyes reached to 912.71 and 473.95 mg/g, respectively in a few minutes. Density functional theory (DFT) result showed that the adsorption was mainly promoted through π-π interaction, hydrogen bonding, and van der Waals interaction. In conclusion, DESs-PANI@Fe 3 O 4 prepared by a facile strategy has the ability to remove dyes from wastewater continuously and efficiently, which provides a new concept for the industrial application of green DESs-based magnetic nanosphere adsorbent. [ABSTRACT FROM AUTHOR]

Water pollution has been made worse by the widespread use of organic dyes and their discharge, which has coincided with the industry's rapid development. Piezoelectric catalysis, as an effective wastewater purification method with promising applications, can enhance the catalyst activity by collecting tiny vibrations in nature and is not limited by sunlight. In this work, we designed and synthesized intriguing WS 2 /Bi 2 WO 6 heterojunction nanocomposites, investigated their shape, structure, and piezoelectric characteristics using a range of characterization techniques, and used ultrasound to accelerate the organic dye Rhodamine B (RhB) degradation in wastewater. In comparison to the pristine monomaterials, the results demonstrated that the heterojunction composites demonstrated excellent degradation and stability of RhB under ultrasonic circumstances. The existence of heterojunctions and the internal piezoelectric field created by ultrasonic driving work in concert to boost catalytic performance, and the organic dye's rate of degradation is further accelerated by the carriers that are mutually transferred between the composites. [Display omitted] • RhB degradation with up to 95% degradation rate. • The material is easy to synthesize, green and stable. • Bi 2 WO 6 provides more active sites for heterojunction composites. • The presence of heterojunctions shifts carriers to lower energy levels. • Ultrasonic driving generates unique built-in electric field to enhance carrier mobility. [ABSTRACT FROM AUTHOR]