Search

New azo Schiff base disperse dyes based on a chromene moiety were synthesized by reacting (2-amino-7-hydroxy-4-(4-methoxyphenyl)-4 H-chromene-3 carbonitrile) and(2-amino-4-(3,4-dimethoxyphenyl)-7-hydroxy-4 H-chromene-3-carbonitrile), with vanillin and ninhydrin, producing new chromene Schiff base derivatives, which in turn were coupled with 2-chloro-4-nitroaniline diazonium salt to give new 4 azo disperse dyes (1–4). The structures of the prepared dyes were confirmed using elemental analysis, 1HNMR spectroscopy, mass spectrometry, and IR. The synthesized dyes were applied to polyester and nylon fabrics using different dyeing techniques: high temperature- high pressure, and ultrasonic dyeing methods. The highest K/S values for all investigated dyes were achieved usinga high temperature-high pressure dyeing technique. Also, the color reflectance of all synthesized dyes with different dyeing shades (1%, 2%, and 3%) was obtained. The fastness properties of the dyed samples using the investigated dyes showed good color fastness toward light, washing, rubbing, and perspiration fastness. The presence of a chromene moiety and Schiff base in the investigated dyes promotes a higher antimicrobial activity on nylon and polyester fabrics against all tested bacteria (E. coli gram-negative and Staphylococcus aureus gram-positive) and two fungi, Aspergillus Niger and Candida albicans. [ABSTRACT FROM AUTHOR]

Introduction: Subjective surgeon interpretation of near-infrared perfusion video is limited by low inter-observer agreement and poor correlation to clinical outcomes. In contrast, quantification of indocyanine green fluorescence video (Q-ICG) correlates with histologic level of perfusion as well as clinical outcomes. Measuring dye volume over time, however, has limitations, such as it is not on-demand, has poor spatial resolution, and is not easily repeatable. Laser speckle contrast imaging quantification (Q-LSCI) is a real-time, dye-free alternative, but further validation is needed. We hypothesize that Q-LSCI will distinguish ischemic tissue and correlate over a range of perfusion levels equivalent to Q-ICG. Methods: Nine sections of intestine in three swine were devascularized. Pairs of indocyanine green fluorescence imaging and laser speckle contrast imaging video were quantified within perfused, watershed, and ischemic regions. Q-ICG used normalized peak inflow slope. Q-LSCI methods were laser speckle perfusion units (LSPU), the base unit of laser speckle imaging, relative perfusion units (RPU), a previously described methodology which utilizes an internal control, and zero-lag normalized cross-correlation (X-Corr), to investigate if the signal deviations convey accurate perfusion information. We determine the ability to distinguish ischemic regions and correlation to Q-ICG over a perfusion gradient. Results: All modalities distinguished ischemic from perfused regions of interest; Q-ICG values of 0.028 and 0.155 (p < 0.001); RPU values of 0.15 and 0.68 (p < 0.001); and X-corr values of 0.73 and 0.24 (p < 0.001). Over a range of perfusion levels, RPU had the best correlation with Q-ICG (r = 0.79, p < 0.001) compared with LSPU (r = 0.74, p < 0.001) and X-Corr (r = 0.46, p < 0.001). Conclusion: These results demonstrate that Q-LSCI discriminates ischemic from perfused tissue and represents similar perfusion information over a broad range of perfusion levels comparable to clinically validated Q-ICG. This suggests that Q-LSCI might offer clinically predictive real-time dye-free quantification of tissue perfusion. Further work should include validation in histologic studies and human clinical trials. [ABSTRACT FROM AUTHOR]

This study investigated the decolorization and detoxification of a dye originating from a feather-dyeing house using the laccase enzyme. Efficient decolorization was achieved under a wide range of environmental conditions, including pH, temperature, enzyme loading, and dye concentration. The decolorization rate reached up to 98% within 10 min when the mediator acetosyringone was present. Decolorization was attributed to the degradation of the dye by laccase, as analyzed using liquid chromatography-mass spectrometry (LC–MS). At least three dominant intermediates (m/z 167.993, 194.475, 118.040) were identified, deriving from the original dye (m/z 521.044). Compared to the non-decolorized dye solution, the decolorized dye ones at various concentrations exhibited lower toxicity towards aerobic activated sludge (AS). This was evident from the significantly higher respiratory intensity of AS, with an O₂ uptake of 35 mg for the decolorized solution versus 11 mg for the non-decolorized solution after 12 h at a 100 mg/L dye concentration. The results suggest that laccase-catalyzed decolorization could serve as an effective pretreatment method for traditional activated sludge (AS)-based processes, thereby enhancing the overall treatment performance of dye wastewater. [ABSTRACT FROM AUTHOR]

Semi-rigid V-shaped bis(N,N-trimellitoyl)-4,4′-oxydianiline linker was designed to construct a novel mesoporous cobalt (II) metal organic framework (Co-MOF). Optical band gap of 3.23 eV was obtained using a Tauc formula, which confirms the semiconducting property of the synthesized Co-MOF. Further, the resulting Co-MOF, as photocatalyst, was investigated in environmental application for the reduction of toxic Cr (VI) to less toxic Cr (III) as well as in the degradation of organic rhodamine B (Rh B) dye in an aqueous medium under natural sunlight. As pH value is essential for the Cr (VI) reduction reaction, thus control experiment was conducted in the acidic pH range 2–6, where 90.76, 77.23 and 37.43% of reduction was observed at pH of 2, 4 and 6, respectively. Furthermore, the degradation of Rh B dye was also performed, where 98.89% degradation obtained within 90 min. The recyclability test was also assessed for Cr (VI) reduction reaction at pH 2 and for degradation of Rh B. [ABSTRACT FROM AUTHOR]

Textile industry uses large quantities of different dyes to fulfill the rapidly growing demand for the dyed textile products, resulting in more dye consumption, greater dye discharge as textile dyeing effluent, and higher cost. To decrease the dyes consumption, this research evaluates the performance of novel ozone-based dyeing processes for cotton fabric. So far, reported ozone-based processes for textile involve the usage of high ozone intensity for removing impurities, discoloration of solution, color fading in denim and other fabrics. This research is a first effort, which concentrates on the performance enhancement of the exhaust dyeing process for cotton fabrics through the application of controlled and lower amount of ozone. In this research, ozone dosage is controlled through ozone generator knob to only 0.5 g/h (10%), 1 g/h (20%), 1.5 g/h (30%), 2 g/h (40%), and 2.5 g/h (50%). In contrast, ozone dosage reaches up to 60 g/h in cotton bleaching. This research evaluates the four ozone-based dyeing processes for cotton fabrics using two primary reactive dyes and two primary direct dyes under different concentrations of ozone. Effect of ozonation was evaluated for both direct and reactive dyes at four stages, namely during dyeing, dry ozonation before dyeing, pre-wet ozonation before dyeing, and ozonation after dyeing. Results showed that K/S value of the optimized ozone-based processes was better than the conventional exhaust process. For instance, K/S value for benchmarked conventional dyed sample was 2.147 for reactive yellow, and it was 3.271 (33.5% higher) for the "ozonation after dyeing" process. Similar trends were observed for many other trials, resulting in higher K/S value. In addition, the fastness properties of the optimized processes were comparable with the conventional exhaust process. FTIR and SEM analysis were also performed on selective ozone dyed fabrics. [ABSTRACT FROM AUTHOR]

Textile dyes are frequently disposable in aqueous effluents, making it difficult to remove them from industrial effluents before their release to natural waters. This paper deals with the fabrication of cellulose-based adsorbents by reacting nanocelulose crystalline (nanocel) with N-[3-(trimethoxysilyl)propyl]ethylenediamine (TMSPEDA), forming the hybrid (silylpropyl)ethylenediamine@nanocellulose (SPEDA@nanocel), which was employed as adsorbent for the uptake of reactive yellow 2 dye (RY-2) from aqueous effluents. Characterisation of SPEDA@nanocel was carried out using FTIR, SEM–EDS, XRD, TGA, surface area, pHpzc, and hydrophobicity/hydrophilicity ratio (HI). Also, adsorption studies were thoroughly investigated. The effect of initial pH indicated that the maximum uptake of RY-2 takes place at pH 2, which is an indication of the electrostatic mechanism. The kinetic data carried out with 250 and 500 mg L−1 RY-2 with SPEDA@nanocel followed better the nonlinear fractional-like pseudo-first-order model. The t0.5 and t0.95 for the dye uptake were about 30 and 141 min, respectively. The equilibrium data from 10 to 45 °C indicated that the Liu isotherm model was the best-fitted isothermal model. The maximum sorption capacity attained was 112.3 mg g−1 at 45 °C. The thermodynamic data have shown that the equilibrium was favorable and endothermic, and the ΔH° was compatible with an electrostatic attraction between RY-2 and SPEDA@nanocel. Experiments of desorption of loaded adsorbent showed promising results for real applications since at least 5 adsorption/desorption cycles could be employed without significant changes in the recovery and with high precision. [ABSTRACT FROM AUTHOR]

Azo dye-laden textile wastewater must be treated before release due to various health and environmental concerns. Bioremediation of textile wastewater, however, is a challenge owing to its alkaline and saline nature as mesophilic microbes, in general, are either not able to thrive or show less efficiency under such hostile environment. Thus, pre-treatment for neutralization or salinity removal becomes a prerequisite before applying microbes for treatment, causing extra economical and technical burden. Extremophilic bacteria can be the promising bioremediating tool because of their inherent ability to survive and show toxicants removal capability under such extreme conditions without need of pre-treatment. Among extremophiles, halophilic and alkaliphilic bacteria which are naturally adapted to high salt and pH are of special interest for the decolorization of saline-alkaline-rich textile wastewater. The current review article is an attempt to provide an overview of the bioremediation of azo dyes and azo dye-laden textile wastewater using these two classes of extremophilic bacteria. The harmful effects of azo dyes on human health and environment have been discussed herein. Halo-alkaliphilic bacteria circumvent the extreme conditions by various adaptations, e.g., production of certain enzymes, adjustment at the protein level, pH homeostasis, and other structural adaptations that have been highlighted in this review. The unique properties of alkaliphiles and halophiles, to not only sustain but also harboring high dye removal competence at high pH and salt concentration, make them a good candidate for designing future bioremediation strategies for the management of alkaline, salt, and azo dye-laden industrial wastewaters. [ABSTRACT FROM AUTHOR]

Purpose: The accuracy of surgery for patients with solid tumors can be greatly improved through fluorescence-guided surgery (FGS). However, existing FGS technologies have limitations due to their low penetration depth and sensitivity/selectivity, which are particularly prevalent in the relatively short imaging window (< 900 nm). A solution to these issues is near-infrared-II (NIR-II) FGS, which benefits from low autofluorescence and scattering under the long imaging window (> 900 nm). However, the inherent self-assembly of organic dyes has led to high accumulation in main organs, resulting in significant background signals and potential long-term toxicity. Methods: We rationalize the donor structure of donor–acceptor-donor-based dyes to control the self-assembly process to form an ultra-small dye nanocluster, thus facilitating renal excretion and minimizing background signals. Results: Our dye nanocluster can not only show clear vessel imaging, tumor and tumor sentinel lymph nodes definition, but also achieve high-performance NIR-II imaging-guided surgery of tumor-positive sentinel lymph nodes. Conclusion: In summary, our study demonstrates that the dye nanocluster-based NIR-II FGS has substantially improved outcomes for radical lymphadenectomy. [ABSTRACT FROM AUTHOR]

Background: Preserving sufficient oxygen supply to the tissue is fundamental for maintaining organ function. However, our ability to identify those at risk and promptly recognize tissue hypoperfusion during abdominal surgery is limited. To address this problem, we aimed to develop a new method of perfusion monitoring that can be used during surgical procedures and aid surgeons' decision-making. Methods: In this experimental porcine study, thirteen subjects were randomly assigned one organ of interest [stomach (n = 3), ascending colon (n = 3), rectum (n = 3), and spleen (n = 3)]. After baseline perfusion recordings, using high-frequency, low-dose bolus injections with weight-adjusted (0.008 mg/kg) ICG, organ-supplying arteries were manually and completely occluded leading to hypoperfusion of the target organ. Continuous organ perfusion monitoring was performed throughout the experimental conditions. Results: After manual occlusion of pre-selected organ-supplying arteries, occlusion of the peripheral arterial supply translated in an immediate decrease in oscillation signal in most organs (3/3 ventricle, 3/3 ascending colon, 3/3 rectum, 2/3 spleen). Occlusion of the central arterial supply resulted in a further decrease or complete disappearance of the oscillation curves in the ventricle (3/3), ascending colon (3/3), rectum (3/3), and spleen (1/3). Conclusion: Continuous organ-perfusion monitoring using a high-frequency, low-dose ICG bolus regimen can detect organ hypoperfusion in real-time. [ABSTRACT FROM AUTHOR]

How to migrate text-to-image models based on pre-trained diffusion models to adapt them to domain generation tasks is a common problem. In particular, the generation task for Chinese landscape paintings with unique characteristics suffers from a scarcity of fine-grained contextual details specific to such artwork. Moreover, the use of substantial amounts of non-landscape painting data during pre-training predisposes the model to be swayed by alternative visual styles, thereby leading to generated images that inadvertently lack the distinctive traits inherent to Chinese paintings. In this paper, we propose a Fine-grained Hierarchical Semantic Adapter for Chinese landscape paintings generation, namely FHS-adapter. The method orchestrates the diffusion process in a batch-wise manner, leveraging external fine-grained multi-perspective information to guide it. It gradually diminishes the influence of other style images embedded in the pre-trained diffusion model, ultimately preserving a greater number of landscape painting elements. The encoder was also replaced with the Taiyi-CLIP encoder, which is adapted for Chinese. We propose T2ICLP, a multimodal dataset containing 10,000 high-quality image-text pairs of Chinese landscape paintings. Unlike previous datasets, this dataset extracts fine-grained textual information from four perspectives, including Meta, Description, Sentiment, Poem. We compared the proposed model with the mainstream diffusion-based T2I models. Through an anonymous user study, our FHS-adapter method performs well in simulating various aspects such as brushwork, e.g.'Gou, Cun, Dian, Ran' means hooking, texturing, dotting, and dyeing, compositional space, elemental proportions, and color usage of different painting genres and artists. Our dataset is available at https://github.com/T2ICLP/t2iclp. [ABSTRACT FROM AUTHOR]

Biologically mediated synthesis of nanomaterials has emerged as an ecologically benign and biocompatible approach. Our study explores enzymatic synthesis, utilizing α-amylase to synthesize ZnO nanoflowers (ZnO-NFs). X-ray diffraction and energy-dispersive X-ray spectroscopy revealed crystal structure and elemental composition. Dynamic light scattering analysis indicates that ZnO-NFs possess a size of 101 nm. Transmission electron microscopy showed a star-shaped morphology of ZnO-NFs with petal-like structures. ZnO-NFs exhibit potent photocatalytic properties, degrading 90% eosin, 87% methylene blue, and 81% reactive red dyes under UV light, with kinetics fitting the Langmuir–Hinshelwood pseudo-first-order rate law. The impact of pH and interfering substances on dye degradation was explored. ZnO-NFs display efficient bacteriocidal activity against different Gram-positive and negative strains, antibiofilm potential (especially with P. aeruginosa), and hemocompatibility up to 600 ppm, suggesting versatile potential in healthcare and environmental remediation applications. [ABSTRACT FROM AUTHOR]

The objective of this study was to establish a solvent-assisted salt-free dyeing method for cotton fabric utilizing commercially available reactive dyes. In this study, the feasibility of substituting water as the dyeing medium with environmentally friendly solvents, specifically ethanol (EtOH), isopropyl alcohol (IPA), and propanol (PrOH), was investigated. Eight commercial reactive dyes, each possessing distinct chemical structures, were examined with various dyeing characteristics including exhaustion, fixation, and fastness properties, in the presence of various alcohols. However, solvent-assisted dyeing exhibited comparable or enhanced color strength (K/S) values, exhaustion, and fixation rates compared to conventional aqueous dyeing. For instance, the RR35 dye demonstrated a substantial increase in K/S values with PrOH, EtOH, and IPA, ranging from 115 to 369% improvement. The substitution of alcohol for water did not affect the wash, rub, and light-color fastness properties, as these properties remained consistently excellent. Solvent-assisted salt-free dyeing of cotton fabrics offers a promising solution to address the environmental impacts of traditional water-based dyeing methods by eliminating the requirement for water and salt. Overall, this study presents a solvent-assisted salt-free dyeing technique and contributes to the field by offering detailed insights into its mechanisms and performance. Our research has the potential to reduce water consumption, eliminate salt usage, and mitigate environmental pollution. [ABSTRACT FROM AUTHOR]

This paper explores the photocatalytic degradation of Reactive Orange 16 (RO16) dye in textile wastewater employing a novel CuO@A-TiO2/Ro-TiO2 nanocomposite. The nanocomposite was synthesized via a hydrothermal technique, resulting in a monoclinic phase of leaf-shaped CuO loaded on a hexagonal wurtzite structure of rod-shaped ZnO, as confirmed by FE-SEM and XRD analyses. Optical experiments revealed band gap energies of 1.99 eV for CuO, 2.19 eV for ZnO, and 3.34 eV for the CuO@A-TiO2/Ro-TiO2 nanocomposite. Photocatalytic degradation experiments showcased complete elimination of a 100 mg/L RO16 solution (150 mL) after 120 min of UV light illumination and 100 min of sunlight illumination, emphasizing the nanocomposite's efficiency under both light sources. The study further delves into the application of the CuO@A-TiO2/Ro-TiO2 nanocomposite for the degradation of actual textile wastewater samples under sunlight irradiation. The results underscore the nanocomposite's remarkable efficacy in treating RO16 in textile wastewater, positioning it as a promising candidate for sustainable and efficient wastewater treatment applications. This research contributes valuable insights into the development of advanced photocatalytic materials for textile dye degradation in wastewater treatment. [ABSTRACT FROM AUTHOR]

This paper explores the photocatalytic degradation of Reactive Orange 16 (RO16) dye in textile wastewater employing a novel CuO@A-TiO2/Ro-TiO2 nanocomposite. The nanocomposite was synthesized via a hydrothermal technique, resulting in a monoclinic phase of leaf-shaped CuO loaded on a hexagonal wurtzite structure of rod-shaped ZnO, as confirmed by FE-SEM and XRD analyses. Optical experiments revealed band gap energies of 1.99 eV for CuO, 2.19 eV for ZnO, and 3.34 eV for the CuO@A-TiO2/Ro-TiO2 nanocomposite. Photocatalytic degradation experiments showcased complete elimination of a 100 mg/L RO16 solution (150 mL) after 120 min of UV light illumination and 100 min of sunlight illumination, emphasizing the nanocomposite's efficiency under both light sources. The study further delves into the application of the CuO@A-TiO2/Ro-TiO2 nanocomposite for the degradation of actual textile wastewater samples under sunlight irradiation. The results underscore the nanocomposite's remarkable efficacy in treating RO16 in textile wastewater, positioning it as a promising candidate for sustainable and efficient wastewater treatment applications. This research contributes valuable insights into the development of advanced photocatalytic materials for textile dye degradation in wastewater treatment. [ABSTRACT FROM AUTHOR]

Background: Near-infrared fluorescence (NIRF) angiography with intraoperative administration of indocyanine green (ICG) has rapidly disseminated in clinical practice. Another clinically approved, and widely available dye, methylene blue (MB), has up to now not been used for this purpose. Recently, we demonstrated promising results for the real-time evaluation of intestinal perfusion using this dye. The primary aim of this study was to perform a quantitative analysis of bowel perfusion assessment for both ICG and MB. Methods: Four mature female Landrace pigs underwent laparotomy under general anesthesia. An ischemic bowel loop with five regions of interest (ROIs) with varying levels of perfusion was created in each animal. An intravenous (IV) injection of 0.25 mg/kg–0.50 mg/kg MB was administered after 10 min, followed by NIRF imaging in MB mode and measurement of local lactate levels in all corresponding ROIs. This procedure was repeated in ICG mode (IV dose of 0.2 mg/kg) after 60 min. The quest spectrum fluorescence camera (Quest Medical Imaging, Middenmeer, The Netherlands) was used for NIRF imaging of both MB and ICG. Results: Intraoperative NIRF imaging of bowel perfusion assessment with MB and ICG was successful in all studied animals. Ingress (i/s) levels were calculated and correlated with local lactate levels. Both MB and ICG ingress values showed a significant negative correlation (r = − 0.7709; p = < 0.001; r = − 0.5367, p = 0.015, respectively) with local lactate levels. This correlation was stronger for MB compared to ICG, although ICG analysis showed higher absolute ingress values. Conclusion: Our fluorescence quantification analysis validates the potential to use MB for bowel perfusion assessment besides the well-known and widely used ICG. Further human studies are necessary to translate our findings to clinical applications. [ABSTRACT FROM AUTHOR]

The activated carbon was produced in the first phase of this investigation by chemically activating hazelnut shell waste with H3PO4. Composite materials were obtained by coating the activated carbon with zinc oxide, whose BET surface area was calculated as 1278 m2 g−1. ZnO-doped ZnO/AC composite was synthesized as an adsorbent for its possible application in the elimination of organic dyestuff MB, and its removal efficiency was investigated. Morphological properties of ZnO/AC were characterized using analytical methods such as XRD, SEM, and BET. The adsorption system and its parameters were investigated and modeled using the response surface method of batch adsorption experiments. The experimental design consisted of three levels of pH (3, 6.5, and 10), initial MB concentration (50, 100, and 150 mg L−1), dosage (0.1, 0.3, and 0.5 g 100 mL−1), and contact time (5, 50, and 95 min). The results from the RSM suggested that the MB removal efficiency was 98.7% under the optimum conditions of the experimental factors. The R2 value, which expresses the significance of the model, was determined as 99.05%. Adsorption studies showed that the equilibrium data fit well with the Langmuir isotherm model compared to Freundlich. The maximum adsorption capacity was calculated as 270.70 mg g−1. [ABSTRACT FROM AUTHOR]

The environmental impact of wastewater discharged from the textile dyeing industry has a significant challenge and influence on aquatic ecosystems and human health if not properly managed. This study aimed to develop a novel cross-linked chitosan composite, denoted as chitosan/fly ash/polyvinyl alcohol (Ch/FA/PVA), as a bio-adsorbent for removing Congo Red (CR) textile dye from industrial wastewater. The synthesis involved the incorporation of FA into the chitosan matrix at various ratios to optimize the process. A specifically tailored composite, Ch/FA0.75/PVA, exhibited superior performance with a remarkable 99.7% CR removal under optimum conditions: adsorbent dose (0.9 g/l), contact time (50 min), and dye concentration (40 mg/l). The characterization of Ch/FA0.75/PVA through SEM–EDX, BET, FTIR, and pHzpc confirmed its suitability for adsorption. Employing Box–Behnken design and analysis of variance (ANOVA) facilitated the optimization of key adsorption variables. The Freundlich model described the adsorption equilibrium, indicating a maximum adsorption capacity of 263.15 mg/g for CR dye. The pseudo-second-order model demonstrated favorable kinetics. The study was scaled up to the practical application of Ch/FA0.75/PVA in a pilot plant for industrial wastewater treatment, revealing substantial removal percentages for dye, color, COD, BOD5 and TDS. This comprehensive approach highlights the promising efficacy of Ch/FA0.75/PVA in addressing environmental concerns associated with textile dye wastewater. [ABSTRACT FROM AUTHOR]

Efficient photocatalysts are crucial for sustainable energy and environmental applications. In this study, Cu-doped TiO2 microporous spheres with varying Cu concentrations (1–5 wt%) were synthesized via hydrothermal techniques for enhanced photocatalytic activity under natural sunlight. Physio-chemical characterization using UV–Vis, XRD, PL, FESEM, and XPS techniques revealed a pure anatase structure with small crystallite sizes (10–15 nm) forming porous spheres. Copper doping induced a decrease in photoluminescence intensity, suggesting improved electron–hole pair separation. Among the samples, CT-2 exhibited superior photocatalytic performance, achieving efficient hydrogen generation (1860 µmol/g/h) and degradation of cationic (methylene blue degradation of 94% in 75 min) and anionic (Congo red degradation of 97% in 14 min) dye under sunlight. However, higher Cu concentrations led to diminished photocatalytic activity, likely due to increased charge trapping and recombination. This study underscores the crucial impact of fine-tuned copper doping concentrations within the TiO2 lattice, highlighting their crucial contribution to enhancing photocatalytic efficiency. [ABSTRACT FROM AUTHOR]

This study focuses on the development of a novel self-cleaning nanofiltration membrane for the efficient removal of the cationic dye methylene blue (MB) from industrial wastewater. The membrane is composed of vinyl resin (VR), cellulose nanofibrils (CNF), and titanium alpha aluminate (TAAL) nanoparticles. The TAAL loading ranged from 1 to 5 wt%, the pH varied from 5 to 10, and the initial MB concentration ranged from 10 to 50 ppm. Using a dead-end filtration system, the (VR/CNF@TAAL) membrane with 5 wt% TAAL at pH 10 demonstrated excellent performances. It achieved a remarkable 98.6% removal efficiency for 30 ppm MB dye, with a maximum adsorption capacity of 125.8 mg/g. The adsorption kinetics analysis revealed that the process followed the pseudo-second-order model, indicating a chemisorption mechanism. The rate constant was determined to be 1.2732 × 10–3 g mg−1 min−1. The Freundlich isotherm model provided a better fit (R2 = 0.996) than the Langmuir model, suggesting multilayer adsorption on the nanocomposite membrane surface. In addition to its high adsorption and filtration capabilities, the (VR/CNF@TAAL) nanocomposite membrane exhibited cost-effectiveness and environmental friendliness as an adsorbent for MB removal from industrial wastewater. The membrane's self-cleaning property further contributes to sustainability by reducing the need for additional chemical treatments. [ABSTRACT FROM AUTHOR]

This study investigates the structural, morphological, and photocatalytic properties of monometallic (Ag and Cu) and bimetallic (AgCu) nanoparticles (NPs) incorporated into ZnO NPs and their photocatalytic performance. X-ray diffraction and Rietveld refinement were employed to analyze the structural characteristics, revealing the formation of a hexagonal wurtzite structure of ZnO and cubic phases of Ag and Cu within the metal-decorated NPs. Scanning electron microscopy provided visual evidence of the spherical morphology, with an average particle size of 50 nm. Energy-dispersive X-ray spectroscopy confirmed the successful deposition of Ag, Cu, and AgCu NPs onto the ZnO surface. The photocatalytic efficiency of the NPs was evaluated by the degradation of methylene blue dye under UV light at a wavelength of 254 nm under sunlight irradiation. Under UV light, the bimetallic AgCu/ZnO system exhibited exceptional performance, achieving a degradation rate of about 95% with 10% AgCu/ZnO. Conversely, under sunlight illumination, the monometallic Cu/ZnO and Ag/ZnO NPs exhibited outstanding photocatalytic properties, with degradation rates of about 99 and 98%, respectively. These findings underscore the influence of the light source on photocatalytic performance as well as the significance of the plasmonic effects and charge-transfer mechanisms. [ABSTRACT FROM AUTHOR]

The chief source of water pollution is industrial wastewater containing dyes. In current study, the optimum conditions for removal of Red-XGRL dye by green metal oxide polymeric nanocomposites were determined via batch and column study. The synthesized materials were characterized via SEM, FTIR and thermal analysis. The optimum pH for attaining maximum adsorption capacity of WD, WD-ZnO-PTh, WD-ZnO-PAN and WD-ZnO-PPY was found to be 8 (12.9 mg/g), 10 (30.2 mg/g), 11 (35.8 mg/g) and 11 (40 mg/g), respectively, and optimum dose was found to be 0.05 g/50 mL. The highest adsorption potential for all composite materials was attained within 90 min and maximum adsorption potential for WD (40.8 mg/g), WD-ZnO-PTh (60.7 mg/g), WD-ZnO-PAN (70.4 mg/g) and WD-ZnO-PPY (86.3 mg/g) was obtained using 200 mg/L dye concentration at 30 °C. The adsorption data showed better fitness to pseudo-second-order kinetics and Langmuir sorption isotherm giving significant R2 values of 0.95–0.99 and 0.97–0.99, respectively. Thermodynamic study showed exothermic nature of sorption. During column study, optimum adsorbent bed height, dye flow rate and inlet initial dye concentration to attain highest adsorption (35 mgg−1) were determined to be 3 cm, 1.8 mL min−1 and 70 mg/L, respectively. Hence, the present study aimed to remove Red-XGRL dye proved that these green metal oxide polymeric nanocomposites could efficiently be synthesized and utilized for efficient removal of Red-XGRL dye from aqueous solution both in batch and in column mode. [ABSTRACT FROM AUTHOR]

In this work, the efficacy of two metal–organic frameworks (MIL-101(Fe) and NH2-MIL-101(Fe)) in eliminating acetamiprid (ATP) insecticide and eosin Y (EY) dye from aqueous solution is tested. An analysis was conducted on the developed nanocomposite's optical, morphological, and structural characteristics. The adsorption isotherm, kinetics, thermodynamics, reusability, and mechanisms for ATP and EY dye removal were assessed. NH2-MIL-101(Fe) adsorbed 76% and 90% of ATP pesticide and EY dye, respectively after 10 to 15 min in optimum conditions. For both adsorbents, with regard to explaining the isotherm data, the Langmuir model offered the most accurate description. Moreover, the adsorption of ATP and EY dye is described by the pseudo-second-order kinetic model. The maximum adsorption capacities of ATP and EY dye on MIL-101(Fe) were 57.6 and 48.9 mg/g compared to 70.5 and 97.8 mg/g using NH2-MIL-101(Fe). The greatest amount of ATP and EY dye clearance was obtained at a neutral medium for both adsorbents. The results of this investigation demonstrate the effectiveness of MIL-101(Fe) and NH2-MIL-101(Fe) as effective substances in the adsorption process for removing pesticides and dyes from aqueous solution. [ABSTRACT FROM AUTHOR]

In-situ modification of cellulose fibers with titania nanoparticles (TiO2 NPs) (TiO2 NPs-cellulose) was carried out via the sol–gel process using titania sol and fibers of cellulose. Cellulose fibers were extracted from wheat straw, an agricultural waste material, whereas titania sol was prepared from titanium(IV) acetoximate, [Ti{ONC(CH3)2}4]. The synthesized TiO2 NPs-cellulose composite was characterized by FT-IR, SEM–EDX, and XRD analyses. The obtained results exposed that TiO2 NPs were homogeneously dispersed over the surface of cellulose fibers. A study was conducted to compare the photocatalytic activities of TiO2 NPs-cellulose composite and TiO2 NPs towards the degradation of methylene blue and methyl orange dyes under sunlight, and it was observed that the photo-degradation of methylene blue (99.99%) and methyl orange (80.73%) within 160 min is higher in the presence of TiO2 NPs-cellulose composite than TiO2 NPs. The adsorption capabilities of TiO2 NPs-cellulose composite towards Pb2+, Cd2+, and Cr3+ toxic metal ions were also examined, and it was found 44.73 mg. g−1 (89.46%), 38.82 mg. g−1 (77.65%), and 4.42 mg. g−1 (8.85%), respectively. Removal of pollutants from textile industrial effluent were also investigated using TiO2 NPs-cellulose composite under sun light. The results obtained were very promising which shows potential of TiO2 NPs-cellulose composite as an efficient photocatalyst and absorbent for real time applications. [ABSTRACT FROM AUTHOR]

Organic dyes can inflict environmental harm and pose risks to human health, thereby presenting challenges in their treatment within industrial wastewater. Currently, numerous research groups have conducted investigations on the adsorption of organic dyes in industrial wastewater. Herein, this work focuses on the selective adsorption approach towards dyes molecules based on an Anderson-type polyoxometalate (noted as POM-1) as potential adsorbent, which has been functionalized with organic ligands to enhance its negative charge. Adsorption experiments revealed that POM-1 displayed efficient adsorption capabilities towards the cationic dye methyl blue with almost complete adsorption within 25 min, and the adsorption rate was calculated as 98%. A rapid and consecutive filtering experiments have also been performed and further proved the excellent adsorption behavior of POM-1 towards MB. [ABSTRACT FROM AUTHOR]

With the aim of studying the electronic and structural properties of metalloporphyrins, we first prepared the 4-acetoxy-3-methoxy benzaldehyde (1) then by reaction this aldehyde with pyrrole the meso-arylporphyrin, namely the meso-tetrakis(4-acetoxy-3-methoxyphenyl)porphyrin (H2TAMPP) (2) was synthesized. We have also prepared a nickel(II) meso-tetra(aryl)porphyrin with the formula [Ni(TAMPP)] (3). Both two porphyrinic compounds 2–3 have been characterized by UV/Vis, fluorescence, 1H and 13C NMR and IR spectroscopies as well as by MALDI and ESI-HRMS mass spectrometry. Density functional Theory (DFT) calculations at the DFT/B3LYP-D3/6–311 G (d, p) level of theory have been carried out to investigate the HOMO–LUMO orbitals of 2–3 and several global reactive parameters of these two compounds such as the chemical potential, the global hardness, the Mulliken electronegativity, the global softness (S) and the global electrophilicity index. The stability and charge delocalization of 2–3 were studied by natural bond orbital (NBO) analysis. On the other hand, our two porphyrinic species 2–3 were theoretically studied for the adsorption of NO2 and H2S gases using the B3LYP/6-31G (d) bases method. Furthermore, H2TAMPP (2) and its corresponding Ni(II) complex (3) were tested as catalysts of the degradation of the methylene blue (MB) and the methyl orange (MO) dyes using an aqueous solution of hydrogen peroxide. [ABSTRACT FROM AUTHOR]

Objective: Oral glucose tolerance test (OGTT) and glycated haemoglobin (HbA1c) have many limitations in diagnosing prediabetes. Glycated albumin (GA) estimation can be a potential tool for its early diagnosis. The present study aims to analyze the diagnostic efficacy of GA to identify prediabetes. Methods: Prediabetics (n = 406) and healthy (n = 406) subjects were included. OGTT was used as the diagnostic standard for identifying prediabetes. HbA1c was estimated in a Bio-Rad D-10 analyzer based on the High-Performance Liquid Chromatography (HPLC) method. GA was measured using the enzyme-linked immunosorbent assay (ELISA) technique and was expressed as a percent of total albumin. Total albumin was measured by the modified bromocresol Purple (BCP) dye-binding method in Siemen's autoanalyzer. Results: HbA1c (5.83 ± 0.57%) and GA (14.43 ± 1.92%) were significantly higher (p < 0.05) in the prediabetics as compared to healthy individuals. Both HbA1c and GA showed a significantly positive correlation with fasting plasma glucose (FPG) and 2-h plasma glucose. However, the correlation was stronger with 2-h plasma glucose for both parameters. GA and HbA1c also showed a significant positive correlation with each other. HbA1c, at 5.7% cut-off, predicted prediabetes with 74% sensitivity and 90% specificity. At the cut-off of 13.5%, GA showed 66% sensitivity and 85% specificity to identify pre-diabetes. The sensitivity of the combined tests was significantly greater than that for HbA1c alone (84% combined versus 74% HbA1c). Conclusion: GA, combined with HbA1c, can be used as a screening test for identifying pre-diabetes. Early diagnosis and interventions could prevent disease progression and limit dreadful complications. [ABSTRACT FROM AUTHOR]

The rising pollution by synthetic dyes from the textile industry is a serious health problem calling for safer chemicals and textile production methods. As an alternative, bio-based colorants are increasingly used for food, cosmetics, flavors, medical applications. Here we review bio-based textile dyeing with focus on dye classification, methods to improve dyeing, and mordants and bio-mordants. Dyes are classified according to their origin such as plant, animal, mineral, microbes, and waste; their chemical structure, e.g., indigoid, flavonoid, and tannin dyes; their color; and their application such as mordant dyes and direct dyes. Methods to improve dyeing include sonication, plasma, ultraviolet, microwave, and gamma irradiation. Most bio-based dyes are biodegradable, renewable, non-hazardous, non-allergic, and simple to use. Yet bio-based dyes are limited by poor color fastness and a constrained palette of shades. These limitations can be resolved by using mordants on textile materials. Bio-mordants enhance the bonding of natural dyes to the fabric, resulting in textiles that exhibit excellent washing fastness. [ABSTRACT FROM AUTHOR]

Low-quality cotton fibers are a low-value waste material within the cotton industry. Upcycling and transforming into high-value materials are highly desired. This study investigates upcycling fibers into hydrogel biosorbents and assesses their efficacy in dye adsorption. An effective gelation approach was employed via simply dropping droplets of suspension mixture of sodium alginate and fibers into acidic bath. Resulting composite hydrogel beads were utilized for dye removal. Composite beads successfully immobilized less than 70 wt% of fibers and achieved a significant improvement in thermal stability. Composite beads with 50 wt% fibers and alginate showed no decrease in methylene blue adsorption capacity. This outcome was unexpected considering the lower dye adsorption capacity of fibers than alginate, particularly notable since it indicated that reduced quantities of the more costly sodium alginate were sufficient to achieve comparable dye adsorption capacity. Mechanistic study unveiled that both the loose crosslinking structure and the electrostatic forces were responsible for the unexpected high adsorption capacity of 50% fiber-alginate. This study reports a promising, innovative and effective upcycle strategy for the first time that can transform fibers into high-value biosorbents without compromising dye adsorption capability. [ABSTRACT FROM AUTHOR]

Photocatalysis is widely used for wastewater treatment as it is environmentally friendly through elimination of harmful organic compounds by mineralizing it to carbon dioxide and water under light illumination. Morphology control of polyaniline (PANI) is thought to affect the specific surface area and conductivity of the composites which subsequently contribute toward the photodegradation performance. In this research study, a binary system of PANI–TiO2 photocatalyst with different morphologies including nanotubes, nanofibers, nanospheres, star micro-/nanostructure and leaf micro-/nanostructure was fabricated for photodegradation of reactive black 5 (RB5) dye under visible light irradiation. Based on the characterization, PANI–TiO2 composites managed to reduce band gap to 2.68–2.72 eV which is proven to be easily activated under visible light region. Meanwhile, the photoluminescence analysis showed that the electron hole (e−h+) recombination was also retarded to provide opportunity for more radical generation. The PANI nanotubes (NT-PANI–TiO2) demonstrate highest photodegradation efficiency of 54.4% after 2 h. Interestingly, PANI leaf micro-/nanostructure (L-PANI–TiO2) shows highest increment of 35.3% of L-PANI to 48.8% of L-PANI–TiO2. This demonstrates the effectiveness of PANI nanotubes and leaf structures along with TiO2 as potential photocatalyst composite. [ABSTRACT FROM AUTHOR]

Zinc-doped CuAl2O4 (Zn-CuAl2O4) nanofiber membranes with a high specific surface area, multi-pore structure, and a partial inverse spinel structure were successfully fabricated by controlling the electrospinning process and calcination atmospheres. The excessive doping of Zn2+ ions results in the formation of ZnAl2O4/CuAl2O4 fiber membrane, which has a poor UV-Vis absorption ability. The diameter of Zn-CuAl2O4 nanofibers is about 80 nm, and the specific surface area of the Zn-CuAl2O4 nanofiber membrane is 45.2 m2/g. XRD and XPS results indicate that Zn-CuAl2O4 nanofiber membranes contain spinel and inverse spinel phases. Compared with pure spinel CuAl2O4 nanofiber membranes, the UV-Vis absorption ability of the Zn-CuAl2O4 nanofiber membrane is enhanced, and transient photocurrent intensity was increased from 0.14 mA/cm2 to 0.16 mA/cm2. The free radical capture experiments and EPR spectra indicate that huge ·O2− are generated on the surface of the Zn-CuAl2O4 nanofiber membrane, and the photocatalytic degradation efficiency of MB is increased by 14%. The Zn-CuAl2O4 nanofiber membranes exhibit excellent cycling stability and have great potential for photocatalytic degradation of dye wastewater. [ABSTRACT FROM AUTHOR]

The amine-based cobalt phthalocyanine loaded titanium dioxide nanocomposite (α-nBACoPc/TiO2) was synthesized utilizing a one-pot method. Afterward, a thorough analysis of the nanocomposites' structural and optical properties was conducted. The crystalline character of the composite is shown by X-ray powder diffraction. The successful synthesis of α-nBACoPc/TiO2 nanomaterials was validated by infrared spectroscopy. The samples' optical studies reveal a gradual diminution of the composites' optical band gap. Nanocomposites were used in the degradation of synthetic dyes (rhodamine B), and it was discovered that after 150 min of simulating sunlight exposure, the composite α-nBACoPc/TiO2 (2:100) exhibited the best degradation; about 90% of the organic material had been broken down. This may be due to the synergistic action of α-nBACoPc and TiO2, which significantly increases the efficiency of light utilization. The ideal properties of positive catalytic activity of the central ion and high specific surface area of the composite accelerate charge transport and reduce charge complexation. Cycling experiments have demonstrated the good stability of the nanocomposite. The potential of nanocomposites (α-nBACoPc/TiO2) in the area of industrial waste dye degradation is thus confirmed by this investigation. [ABSTRACT FROM AUTHOR]

Water contamination caused by textile dyes can affect human health, calling for effective treatment method. Here, we report the preparation of MgFe2O4/C composite through hydrothermal method to adsorb three dyes including rhodamine B, methyl orange (MO) and acid yellow 17 (AY) in water. MgFe2O4/C obtained a surface area of 692.32 m2/g and MgFe2O4 particles were well-dispersed on porous carbon matrix. Taguchi experimental design (L16) was conducted to test the effect of four factors, including initial concentration, adsorbent dosage, contact time and pH at different four levels. pH was a first-ranked factor for adsorption of all three dyes with the highest contribution between 33.20 and 55.61%. The highest capacity (158.12 mg/g) was determined for MO dye adsorption under a concentration of 40 mg/L, pH 3, a dose of 0.05 g/L, and a duration of 240 min. The experiments of MgFe2O4/C reusability were performed, reaching at least fourth cycles offering potential for reuse. It is recommended that Taguchi orthogonal array design can be well adopted to reach the best condition of organic dyes adsorption by MgFe2O4/C composite. [ABSTRACT FROM AUTHOR]

A new aqua-tricaesium-sodium polymetavanadate compound, [Cs3Na(VO3)4(H2O)] (1), was synthesized by reacting caesium chloride and sodium metavanadate at ambient pH. The structure was characterized and identified using single-crystal X-ray diffraction, Fourier-transform infrared spectroscopy, Raman spectroscopy, and energy dispersive X-ray analysis (EDS). Compound (1) crystallizes in an orthorhombic system with a Pnma space group, and cell parameters a = 11.6554(4), b = 8.3408(2), c = 16.1121(5). Vanadium has tetrahedral coordination connected to the next vanadium atom through an oxygen bridge. The infinite zigzag metavanadate chains formed by corner-sharing VO4 tetrahedral constitute a1D building block. The chains were laterally connected through Cs, Na, and H2O. This connectivity generates continuous 2D layers within the ab plane. The photocatalytic performance of (1) was evaluated by measuring the degradation of methylene blue under visible light. The results confirmed the efficiency of the photocatalytic activity because of the narrowed bandgap energy of 2.18 eV, and 85% degradation rate, making it suitable for absorbing visible light. The paper reports the synthesise and characterization of a new isopolyvanadate compound, [Cs3Na(VO3)4H2O], which contains vanadim in the five oxidation state with tetrahedral coordination. It forms metavanadate chains interconnected by caesium and sodium cations. The photocatalytic activity was tested by degrading methylen blue under visible light irradiation. The results showed decent activity attributed to the narrowed bandgap energy of 2.18 eV. [ABSTRACT FROM AUTHOR]

Photocatalytic processes are able to decompose dyes and toxic substances in the water environment. This fascinating topic can address many environmental concerns about polluted water. Zinc oxide is widely used as a photocatalyst in various nanocomposites. In this study, the formation of a nanostructure including cyclodextrin and ZnO has been investigated by density functional theory (DFT) in gas and aqueous phases at B3LYP and M06-2X functional levels. The calculated binding energies and natural bond orbital (NBO) analysis indicate the existence of strong chemical interactions of ZnO with the inside of the cyclodextrin (CD) cavity during CD-ZnO formation. In addition, the interaction of methylene blue (MB) and phenol red (PhR) dyes with CD-ZnO nanostructure has been investigated. The dyes' adsorption energy values on the CD-ZnO ranged from − 243.4 to − 55.9 kJ. These energies and the density of states diagrams in their complexes confirm the strong interaction of MB and PhR with CD-ZnO. This strong interaction of dyes with nanostructure can support the mechanisms that lead to the photocatalytic degradation of dye molecules. [ABSTRACT FROM AUTHOR]

Using fluorescence spectroscopy, the two-photon absorption cross sections of aqueous solutions of the styryl dye trans-4-[4-(dimethylamino)styryl]-1-methylpyridinium iodide (DASPI) and its inclusion complexes with cucurbit[n]urils (CB[n] n = 6–8) have been measured. A nonmonotonic dependence of the cross section on the excitation wavelength and on the cavitand cavity size has been revealed. Compared to the free dye, a sevenfold increase in the two-photon absorption cross section has been observed in DASPI inclusion complexes with CB[8] at an excitation wavelength of 980 nm. [ABSTRACT FROM AUTHOR]

Natural pigments are becoming increasingly popular owing of their reliability. Microbial pigments provide an alternative to natural colours. A total of 24 fungal cultures were collected from leaf bits of Senna auriculata, with one strain (FNG1) producing an extracellular red orange pigment. Nigrospora oryzae was confirmed by using physical criteria and molecular phylogenetic study by using ITS and β- tubulin analysis. In EtOAc, the crude red pigment was the most soluble. The TLC analysis was used to partly purify the natural pigment. The partially purified fungal pigment was used in successive bioprospecting studies. The antimicrobial activity of the partially purified sample was assessed against eight human pathogens, with Leucobacter AA7 showing the largest zone of inhibition (200–500 µg/mL). The compound's DPPH scavenging activity enhanced from 38.2 to 67.9%, with an IC50 value of 34.195 ± 2.33 µg/mL. Cancer cells were suppressed by partly pure fungal pigment, but non-cancerous HEK 293 cells were unaffected. The GC–MS analysis was used to characterize the molecule present in the partly purified pigment. In addition, the cotton textiles have the greatest staining capability for crude mycobial pigment, which dyes quickly and has a negative cytotoxicity. [ABSTRACT FROM AUTHOR]

This article reports the nonlinear refractive index (n2) and nonlinear absorption coefficient (β) of acid blue 129 (AB 129) dye-doped polyvinyl alcohol (PVA) thin film with different dye concentrations using Z-scan technique. The experimental technique consists of a continuous wave laser with 5 mW power working at 635 nm wavelength. The normalized transmittance curve suggests that the dye-doped polymer film exhibits a self-defocusing nonlinear index of refraction and a large nonlinear absorption coefficient ascribed to the behaviour of reverse saturable absorption. The order of third-order NLO susceptibility of the sample is estimated to be 10‒5 esu. The dye-doped polymer films show a low-limiting threshold of 0.15 kW cm–2 at 0.04 mM dye concentration and believed that the prepared thin film is a suitable candidate for application in optical limiting. The self-diffraction pattern is observed at far-field and estimated the nonlinear refractive index of the thin film using this technique. The results of the nonlinear refractive index of the sample obtained from the self-diffraction method are comparable with Z-scan results. [ABSTRACT FROM AUTHOR]

Herein, we report the nonlinear refractive index and nonlinear absorption coefficient of anthraquinone dye (disperse blue 14)-doped polymer film using a facile Z-scan technique. The Z-scan studies were carried out using a semiconductor diode laser with a constant power output of 5 mW at a wavelength of 635 nm as the source of excitation. The Z-scan technique consists of closed and open aperture methods, which revealed the self-defocusing and reverse saturable absorption mechanisms based optical nonlinearity. The third-order nonlinear optical susceptibility (χ(3)) of dye-doped polymer film was estimated to be in the order of 10–5 esu. Optical limiting (OL) behaviour of the polymer film with different dye concentrations was performed under the same experimental conditions and found to be a low OL threshold of 1.45 × 102 W cm–2 at 0.04 mM dye concentration. Self-diffraction ring pattern of the polymer film was also noticed in the far field. The overall results found that the dye-doped polymer film is a potential material for photonics and optoelectronics applications. [ABSTRACT FROM AUTHOR]

Dyes can be determined as a substance that creates many environmental issues leading to the death of aquatic life, plants and all living organisms. Dye removal can be done by several physical, chemical and biological methods, including the photocatalytic method. Photocatalysis is a method in which light energy is used to degrade the dye. This technique is low-cost and eco-friendly, and it degrades many harmful substances from organic dyes compared to other techniques. The prime aim of the present work is to degrade the largely used organic dyes such as methylene blue, malachite green and crystal violet using EDTA-doped FeZnS2 and Leishman stain-doped FeZnS2 thin films. The doped FeZnS2 thin films were fabricated using the co-precipitation method. Thin fabricated films are characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX) and UV–Visible spectroscopy (UV). These characterization studies show an active photo response indicating effective dye degradation. Based on the absorption studies of UV spectroscopy measurements after 60 min, the degradation efficiency of methylene blue, crystal violet and malachite green using EDTA-doped FeZnS2 are 76, 85 and 90, respectively. Similarly, the degradation efficiency after 60 min of methylene blue, crystal violet and malachite green using Leishman stain-doped FeZnS2 are 82, 79 and 89, respectively. [ABSTRACT FROM AUTHOR]

This comprehensive review extensively explores the potential applications of MXenes as versatile materials in the realm of photocatalysis, with a specific focus on their efficacy in mitigating hazardous dyes and CO2 to less harmful and friendly by-products. The review systematically investigates the unique properties that render MXenes well-suited for photocatalytic purposes and provides a thorough examination of their current state of research. It meticulously summarizes the successes and breakthroughs achieved thus far, offering insights into the advancements that have propelled these materials into the spotlight of photocatalytic research. In addition to highlighting achievements, the review critically addresses the challenges and hurdles that impede the full realization of the potential inherent in MXenes. Here, we have also highlighted the stability problem of MXenes and how to overcome this problem for efficient photocatalysis. The mechanism of photocatalysis was also the main theme of this review article and how to overcome the recombination of photogenerated charges. By identifying these challenges, the review serves as a valuable resource for researchers, providing a roadmap for future endeavours to unlock the untapped capabilities of these materials. It serves as a beacon for environmental researchers, offering valuable insights into the pivotal role these materials can play in creating a more environmentally friendly and safe world. Ultimately, this review contributes significantly to the collective knowledge base and will prove instrumental for researchers and professionals dedicated to environmental protection and sustainable living. Highlights: Hazardous effect of pollutants on environment. Properties and synthesis of MXenes. MXenes promising materials for dyes degradation and CO2 reduction. Mechanism of Photocatalysis for dyes degradation and CO2 reduction. [ABSTRACT FROM AUTHOR]

Herein, a novel nanocomposite based on lanthanum zinc ferrite and nickel tungstate was created by incorporation between (MMT-jeffamine-400) nanoparticles (NPs), chloromethyl styrene as a binder and polymethyl methacrylate monomer using solution polymerization. The as-designed nanocomposites were employed to confiscate xylenol orange "X.O" as an acidic dye and rhodamine B "RhB" as "an amphoteric dye" from colored wastewater. The impact of several parameters such as solution pH, initial dye concentration, the effect of time, and the effect of temperature was explored. The consequences indicated that the pure organoclay had negligible adsorption while that composed of organoclay with PMMA@CMS-polymer incorporated with LaZnFe2O4@NiWO4 particles detached more than 90% for xylenol orange (XO) and 93% for "rhodamine B" molecules. Electrostatic interactions are the predominant factor in the adsorption of cationic and amphoteric adsorbates, as proven by zeta-potential measurement. Additionally, the adsorbent may be regenerate and utilized up to five times with good adsorption capabilities by adding sodium hydroxide. As a result, the removal can be effectively accomplished using the nanocomposite as an adsorbent. The actual and theoretical adsorption capacity values for both dyes at all doses were closely matched, which supported the adsorption kinetics data that fit the pseudo-first order rate model well. The adsorption data's correlation values (0.995 for XO and 0.98 for RhB) indicated that both dyes' Langmuir adsorption would perform well. Furthermore, the adsorption of XO and RhB dyes on the adsorbent is confirmed to be a viable reaction by the negative values of ΔGo. The enhanced adsorbent material for the removal of amphoteric and anionic dyes from waste water is the synthesized LaZnFe2O4 supported NiWO4@D400-MMT@CMS/MMA nanocomposites, which exhibits a reusability affinity of up to five cycles. [ABSTRACT FROM AUTHOR]

Degradation of bromocresol green in alcohol-water solution using ozone micron sized bubbles is reported. A high speed impeller is used to generate micro bubbles of ozone in liquid while ozone is generated using a commercial ozone generator. A 3-level-3-factor Box–Behnken experimental design is used to statistically identify relative importance of the operating parameters studied namely impeller speed, initial concentration of dye and treatment time. Ozone dosage is kept fixed at 4 g/h. Impeller speed is found to be the most dominant factor according to Analysis of Variance (ANOVA) calculations. Kinetics for degradation of bromocresol green in solution is also reported. A second order kinetics is seen to fit the experimental (concentration–time) data, corresponding value of rate constant being 0.0153 L/mg-s. Based on the laboratory scale data a detailed techno-commercial analysis of a scaled up (75 kL/day) plant for ozone based degradation of bromocresol is presented. All relevant economic indicators pertaining to the scaled up plant are reported. A specific treatment cost of Rs. 100/m3 of treated water yields a return on investment (ROI) of 68.77 and discounted payback period of 5 years. [ABSTRACT FROM AUTHOR]

The effect of a thermochromic dye on the viscosity and stability of DMF solutions of polyacrylonitrile (PAN) was studied. The uniformity of the dye distribution in PAN films was characterized. The physicomechanical properties of thermochromic PAN films were studied. [ABSTRACT FROM AUTHOR]

The interaction of indotricarbocyanine dyes with lipid-transfer protein Ns-LTP1 in Dulbecco's phosphate-buffered saline (PBS) was studied. An orthophenylene bridge with a chlorine in the meso-position of the dye was shown to be ineffective as a linker for protein macromolecules without a free cysteine residue. The indotricarbocyanine dye was modified into the N-hydroxysuccinimide ester to obtain a complex of the indotricarbocyanine dye with the Ns-LTP1 protein. A complex of dye molecules with the Ns-LTP1 protein was obtained by mixing a two-phase system of the protein in PBS and the dye activated ester in 1,2-dichloroethane. The half-width of the absorption spectrum increased from 56 to 61 nm; the fluorescence decay time, from 0.3 to 0.5 ns; and the degree of polarization, from 27 to 31% upon formation of the complex. It was established that HCl at concentrations equivalent to its content in gastric juice (0.1–0.5%) led to irreversible destruction of the dye. Capsules that can withstand stomach acid and dissolve in the intestines could be used to treat erosive and ulcerative lesions with peroral administration of the complex. [ABSTRACT FROM AUTHOR]

This study used zinc/iron acetate (as a precursor) and a carboxylic variant of activated carbon (as a matrix) to create nanostructured zinc ferrite (ZnFe2O4). Carboxylic derivative (AC–COOH) of activated carbon was obtained by nitric acid oxidation. Then, enhanced activated carbon's surface was impregnated with ZnFe2O4. ZnFe2O4 nanoparticles with a size range of 25–35 nm and a surface area of 165.8 m2g−1 were proven to have been achieved after the ZnFe2O4 nanostructure was characterized by XRD, FESEM, TEM, UV, PL, BET, and XPS. Using the same testing circumstances, the optimized photocatalyst with 10 wt.% ZnFe2O4 inserted AC demonstrated the best degrading efficeicny to methylene blue (99%) and Reactive red (94%). The Langmuir–Hinshelwood hypothesis, which states that the dye concentration is a first-order function of time, was validated by kinetic investigations. The photocatalyst was shown to be stable after 7 cycles of recycling under optimal circumstances in a study of the reusability of a 10-ZnFe2O4/AC photocatalyst. In addition, PL, TRPL, EIS, and transient-photocurrent response all provide strong evidence for the efficient charge separation in ZnFe2O4/AC. [ABSTRACT FROM AUTHOR]

Photothermal nanoparticles are recent materials which provide additional capacity supply during the photocatalytic reactions. Iron disulfide (FeS2) nanoparticles with unique chemical and optical properties effectively absorb the full broad spectrum and convert the solar energy into chemical energy owing to its small band gap energy of 1.5 eV. However, the fast electron–hole pair recombination reduces the efficiency of FeS2 and depresses the redox reaction. In this novel research, FeS2/CeO2 heterojunctions are prepared for successful decomposition of rhodamine B dye as toxic pollutant belonging to xanthene dye group. CeO2 nanoparticles are fabricated through sol–gel procedure via triton- × 100 as pore directing agent. Nanoparticle's FeS2 is developed by the precipitating process under a N2-atmospheric condition. Various amounts of FeS2 particles were deposited in ultrasonic bath onto the surface of CeO2. The nanostructures, crystalline and optical properties of the solid specimens are evaluated by scanning and transmission electron microscopy (SEM and TEM) with Energy-dispersive X-ray spectroscopy (EDS), x-ray diffraction (XRD), photoluminescence (PL) and diffuse reflectance spectroscopy (DRS) techniques. The photocatalytic efficiency of CeO2, FeS2 and various compositions of FeS2/CeO2 heterojunction was deliberated via following the decomposition of rhodamine B dye under UV radiation at 365 nm. FeS2 efficiently transfers the absorbability of the nanocomposite to deep visible region by decreasing the band gap energy of CeO2 from 2.3 to 1.5 eV revealing that FeS2 determines the optical properties of the nanocomposites. The charge transportation proceeds through type (I) heterojunction with accumulation of the massive charge carriers in the valence and conduction bands of FeS2 nanoparticles. The novel nanocomposite with strong absorbability of nearly full absorption spectrum could be an effective photocatalyst for decomposition of toxic organic dye from various sources of water. [ABSTRACT FROM AUTHOR]

One approach that shows promising for producing hydrogen fuel from solar energy is photoelectrochemical (PEC) water splitting. The main challenge is to design effective photoanodes. Although bismuth vanadate (BiVO4) is an ideal photoanode in terms of absorbing visible light, serious electron–hole recombination and poor charge transport limit its application as a photoanode of PEC. Dye sensitization is the key method to improve electron transfer and light utilization. Herein, an enhanced dye (rhodamine B, RhB)-sensitized BiVO4/BiOCl system was explored. The results show that the process of RhB sensitization BiVO4 requires BiOCl as a bridge. The RhB-sensitized BiVO4/BiOCl system exhibits excellent photoelectrochemical activity, which is attributed to its enhanced photoinduced electron transport and wider visible light response range. This inspiration comes from the mythical story of China, "Cowherd and the Weaver Girl Meet at the Magpie Bridge". The combination of dye sensitization and BiVO4/BiOCl heterojunction explored an energy-saving, efficient and green light-induced system to improve the PEC efficiency. [ABSTRACT FROM AUTHOR]

Dyes as one of the majority critical environmental pollutants from industrial wastewaters, have caused many concerns for researchers. In this research an effective photocatalyst based on La2O3-SiO2 nanocomposite was prepared and evaluated for degradation of toluidine blue (TB) dye. The prepared photocatalyst was illustrated impressive performance in degradation of TB equal to 97% by visible light irritation. Accuracy of synthesized nanocomposite was studied by some technics including FE-SEM, FT-IR, EDX and mapping analysis. Also the effective parameters in degradation percent of TB such as pH, temperature, time, concentration and the amount of nanocomposite were investigated and optimized equal to amounts of 8.0, 25℃, 80 min, 3.0 µg/mL and 0.04 mg respectively. [ABSTRACT FROM AUTHOR]

In this study, mixed phase (tetragonal and monoclinic) Zirconia nanoparticles (ZrO2 NPs) namely, ZS3, ZS7 and ZS10 were synthesized via hydrothermal method at different pH values of (3, 7, 10) respectively. A combination of Powder X-ray diffraction (PXRD), High Resolution Transmission Electron Microscopy (HRTEM), and Selected Area Electron Diffraction (SAED) characterization techniques confirmed the formation of mixed phase ZrO2 nanoparticles. The photocatalytic behavior of synthesized ZrO2 NPs was examined for the degradation of anionic Congo Red (CR) Dye under visible light irradiation. A systematic study of the efficiency of the prepared ZS3, ZS7 and ZS10 nanoparticles was compared and it was found that ZS7 outperformed the ZS3 and ZS10 materials, having removal efficiency of up to 98.9% with 0.1 g of the prepared ZS7 nanoparticles for 75 ppm of Congo Red (CR) dye. Furthermore, the surface area analysis revealed that among the prepared materials, ZS7 exhibited the highest surface area, thereby corroborating the finding of its superior catalytic efficiency. Under the optimized experimental conditions, the degradation of dye followed first-order kinetics. ZS7 showed the highest removal efficiency in just 60 min of contact time for all the CR dye concentrations ranging from 50 to 100 ppm, making it a superior catalyst for the efficient removal of the targeted Congo Red dye. [ABSTRACT FROM AUTHOR]

A low cost imine-decorated linker, 4,4'-(hydrazine-1,2-diylidenedimethylylidene)dibenzoic acid was utilized for the preparation of copper-based metal–organic framework (MOF) denoted as Cu-L via a solvothermal technique. The synthesized MOF material has been fully characterized by different analytical techniques such as Fourier-transform infrared (FT-IR) spectroscopy, powder X-Ray diffraction (PXRD), scanning electron microscopy (SEM), energy dispersive X-Ray spectroscopy (EDX), nitrogen adsorption–desorption isotherm analysis, and thermogravimetric analysis (TGA). It has been found that the coordination of Cu2+ with L considerably reduced the band gap of the L of nearly about 1 eV, which is approximately 26% decline in total. Notably, a narrow band gap of the photocatalyst is an essential requirement for the proficient photodegradation of organic contaminants. An excellent optical properties and narrow band gap of (2.8 eV) of Cu-L ensure their suitability as a photocatalyst for the degradation of methylene blue (MB) dye. In the presence of Cu-L photocatalyst, 84.22% degradation of MB dye was observed after 150 min under sunlight exposure. It is the first time that imine-functionalized MOF was utilized for the degradation of MB dye under sunlight irradiation. For understanding the photodegradation of MB dye by the Cu-L photocatalyst, all the plausible mechanistic studies have been carried out in detail. Both theoretical (with the help of density functional theory (DFT) calculations) as well as experimental studies have been conducted to justify the possible mechanisms for the photodegradation of MB dye by Cu-L. The current work may open a new opportunity to construct a cheap MOF-based photocatalysts for fast degradation of dye contaminants. [ABSTRACT FROM AUTHOR]