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The main challenge for solar cell devices is harvesting photons beyond the visible by reaching the red-edge (650–780 nm). Dye-sensitized solar cell (DSSC) devices combine the optical absorption and the charge separation processes by the association of a sensitizer as a light-absorbing material (dye molecules, whose absorption can be tuned and designed) with a wide band gap nanostructured semiconductor. Conformational and environmental effects (i.e., solvent, pH) can drastically influence the photophysical properties of molecular dyes. This study proposes a combined experimental and computational approach for the comprehensive investigation of the electronic and vibrational properties of a unique class of organic dye compounds belonging to the family of red-absorbing dyes, known as squaraines. Our focus lies on elucidating the intricate interplay between the molecular structure, vibrational dynamics, and optical properties of squaraines using state-of-the-art density functional theory calculations and spectroscopic techniques. Through systematic vibrational and optical analyses, we show that (i) the main absorption peak in the visible range is influenced by the conformational and protonation equilibria, (ii) the solvent polarity tunes the position of the UV–vis absorption, and (iii) the vibrational spectroscopy techniques (infrared and Raman) can be used as informative tools to distinguish between different conformations and protonation states. This comprehensive understanding offers valuable insights into the design and optimization of squaraine-based DSSCs for enhanced solar energy conversion efficiency. [ABSTRACT FROM AUTHOR]

Resonant intermediate states have been proposed to increase the efficiency of entangled two-photon absorption (ETPA). Although resonance-enhanced ETPA (r-ETPA) has been demonstrated in atomic systems using bright squeezed vacuum, it has not been studied in organic molecules. We investigate for the first time r-ETPA in an organic molecular dye, indocyanine green (ICG), when excited by broadband entangled photons in near-IR. Similar to many reported virtual state mediated ETPA (v-ETPA) measurements, no r-ETPA signals are measured, with an experimental upper bound for the cross section placed at 6(±2) × 10−23 cm2. In addition, the classical resonance-enhanced two-photon absorption (r-TPA) cross section of ICG at 800 nm is measured for the first time to be 20(±13) GM, where 1 GM equals 10−50 cm4 s, suggesting that having a resonant intermediate state does not significantly enhance two-photon processes in ICG. The spectrotemporally resolved emission signatures of ICG excited by entangled photons are also presented to support this conclusion. [ABSTRACT FROM AUTHOR]

Developing dyes with high open-circuit photovoltage (Voc) is a vital strategy to improve the power conversion efficiency (PCE) of co-sensitized solar cells (co-DSSCs). Herein, three organic fluorine-containing dyes [YY-ThP(3F), YY-ThP(2F), and YY-ThP(26F)] are designed and synthesized for investigating the fluorine-induced effect on photophysical and photovoltaic performances. Consequently, this effect can significantly broaden the UV–vis absorption spectra of dyes but fail to improve the light-harvesting capability of DSSCs. Strikingly, YY-ThP(3F), featuring 3-position fluorine substitution to cyanoacrylic acid, yields a relatively high Voc compared to the corresponding fluorine-free dye (YY-ThP). Furthermore, the co-sensitization of YY-ThP+YY-ThP(3F) achieves a remarkably high PCE and long-term stability. This work implies that the combination of judicious molecular engineering and co-sensitization is a promising strategy for highly efficient and stable DSSCs. [ABSTRACT FROM AUTHOR]

In response to growing concerns regarding the environmental impact of traditional chemical synthesis methods, this study delves into the phytoconstituents-based green synthesis of copper oxide (CuO) nanoparticles (NPs) as a promising alternative. The study aimed to synthesize CuO NPs using eco-friendly methods with Erythrina variegata and then explore their anticancer, antibacterial, and photocatalytic properties. CuO NPs' structural and optical properties were comprehensively analyzed using UV-vis, XRD, FTIR, XPS, DLS, SEM, and HRTEM, with elemental mapping performed via EDAX. Cytotoxicity assays were conducted on cervical cancer HeLa cells and HEK293 noncancerous cells. The band gap of the CuO NPs was determined to be 3.781 eV, with a crystal size of 17.15 nm and a zeta potential of −23.1 mV. Remarkably, the synthesized nanoparticles exhibited a spherical morphology and demonstrated significant cytotoxicity against HeLa cells with an IC50 value of 48 ± 5 μg mL−1 while displaying lower toxicity towards HEK293 cells. Additionally, the prepared CuO NPs demonstrated dose-dependent anticancer potential, inhibiting cell migration and colony formation, and inducing apoptosis in HeLa cells. Moreover, the antibacterial activity of the prepared CuO NPs against S. aureus and E. coli paralleled that of the standard antibiotic streptomycin. Furthermore, we evaluated the photocatalytic capability of the developed CuO NPs, which demonstrated significant photocatalytic activity with a 91.12% degradation of the organic dye methylene blue in 180 min under UV irradiation, demonstrating their potential for breaking down organic pollutants in the environment. This study emphasizes the eco-friendly synthesis of CuO NPs, promising significant impacts on energy, the environment, and medicine through sustainable approaches. [ABSTRACT FROM AUTHOR]

Comprehensive strategies with the development of advanced materials are required for the remediation of water and land pollution to protect the environment and human health. In this regard, iron oxide catalysts are recognized as preferable catalysts for the heterogeneous photo-Fenton process, which is an efficient technique for degrading organic pollutants in waste water. The present study discusses the photocatalytic performance of iron oxide-based catalysts synthesized from industrial waste red mud for methylene blue degradation under visible light irradiation. XRD studies confirmed the formation of a pure α-Fe2O3 (hematite) phase, whereas the doping of iron oxide with Mn, Cu, and Ce was ascertained by XPS analysis. 3 wt% Cu doped iron oxide with a TOC value of ∼84.7% showed the best removal efficacy to the tune of ∼91% within 60 min of visible light irradiation. Impedance data supports the enhanced charge separation in metal doped α-Fe2O3, which improves the photocatalytic performance. A similar trend was observed in photo-electrochemical (PEC) properties, where Cu doped Fe2O3 showed 2 times higher photocurrent than the bare one. Based on scavenging tests, electrons and hydroxyl radicals (˙OH) were shown to be major players in the photodegradation of pollutants under visible light. A probable mechanism explaining the enhanced e−/h+ pair separation and migration was proposed by examining electrochemical properties. This work has significant implications for wastewater treatment with the efficient use of industrial waste red mud as a cost-effective resource. [ABSTRACT FROM AUTHOR]

In this study, a hydrothermal approach was employed to graft chitosan (Chit)/algae (ALG) with salicylaldehyde (SA), resulting in the synthesis of a biocomposite named salicylaldehyde-based chitosan Schiff base/algae (Chit-SA/ALG). The main objective of this biocomposite was to effectively remove methyl violet (MV), an organic dye, from aqueous solutions. The adsorption performance of Chit-SA/ALG toward MV was investigated in detail, considering the effects of three factors: (A) Chit-SA/ALG dose (ranging from 0.02 to 0.1 g/100 mL), (B) pH (ranging from 4 to 10), and (C) time (ranging from 10 to 120 min). The Box–Behnken design (BBD) was utilized for experimental design and analysis. The experimental results exhibited a good fit with both the pseudo-second-order kinetic model and the Freundlich isotherm, suggesting their suitability for describing the MV adsorption process on Chit-SA/ALG. The maximum adsorption capacity of Chit-SA/ALG, as calculated by the Langmuir model, was found to be 115.6 mg/g. The remarkable adsorption of MV onto Chit-SA/ALG can be primarily attributed to the electrostatic forces between Chit-SA/ALG and MV as well as the involvement of various interactions such as n–π, π–π, and H-bond interactions. This research demonstrates that Chit-SA/ALG exhibits promising potential as a highly efficient adsorbent for the removal of organic dyes from water systems. The novelty of this work comes from introducing a new bio-organic based composite adsorbent of chitosan (Chit) biopolymer and algae (ALG) biomass. Moreover, the functionality and chemical stability of Chit–ALG composite was further developed by grafting process with salicylaldehyde (SA) using hydrothermal process. The incorporation of ALG biomass into polymeric matrix of Chit and grafting process with SA makes Chit a unique hybrid adsorbent toward cationic dye (methyl violet dye). [ABSTRACT FROM AUTHOR]

[Display omitted] • A "Turning waste into treasure" strategy was proposed. • An efficient ARM/NiOOH adsorbent has been successfully prepared. • The adsorption kinetics model has been reasonably established. • 348.0 mg g−1 congo red was adsorbed with a ∼ 100 % adsorption efficiency within 5 min. Extracting functional materials from industrial waste residues to absorb organic dyes can maximize waste reuse and minimize water pollution. However, the extraordinarily low purification efficiency still limits the practical application of this strategy. Herein, the lamellar NiOOH is in-situ anchored on the industrial waste red mud surface (ARM/NiOOH) as an adsorbent to purify organic dyes in wastewater. ARM/NiOOH adsorbent with high specific surface area and porosity provides considerable active sites for the congo red (CR), thereby significantly enhancing the removal efficiency of CR. Besides, we fit a reasonable adsorption model for ARM/NiOOH adsorbent and investigate its adsorption kinetics. Resultantly, ARM/NiOOH adsorbent can remarkably adsorb 348.0 mg g−1 CR within 5 min, which is 7.91 times that of raw RM. Our work provides a strategy for reusing industrial waste and purifying sewage pollution, which advances wastewater treatment engineering. [ABSTRACT FROM AUTHOR]

Pigments play a pivotal role in the cosmetic industry, in which the development of pigments with concurrent color diversity, hydrophobicity, biocompatibility and photostability remains a great challenge. Herein, we report organic–inorganic composite pigments synthesized via a combination of organic dye anions (Ponceau SX and acid green (AG)), layered double hydroxides (LDHs) and octyltriethoxysilane (OTEOS) (denoted as O/Dye-LDHs: O/SX-LDHs and O/AG-LDHs).The prepared composite pigments were characterized via a comprehensive investigation based on X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive spectroscopy (EDS-mapping), Fourier transform infrared (FT-IR) spectroscopy, CIE 1976 L*a*b* color scales, static contact angle measurement and HET-CAM assay. The results confirm the successful intercalation of organic dye anions into the interlayer region of LDHs via host–guest interactions and the surface modification of OTEOS on the layer surface, forming a new kind of hydrophobic organic–inorganic composite pigment with a sandwich structure. LDH layer protection and OTEOS coating play crucial roles in the high photostability, good hydrophobicity and satisfactory biocompatibility of pigments. In addition, O/Dye-LDHs exhibit rich color and color adjustability. Impressively, we applied mixture composite pigments with different O/SX-LDH-to-O/AG-LDH ratios to formulate an eye shadow cream, which present a series of popular and natural colours with water resistance to enhance one's attractiveness and appearance. This work provides a promising strategy for the design of safe and efficient composite pigments, demonstrating their potential application in the field of makeup. [ABSTRACT FROM AUTHOR]

In 1540, in Ingolstadt, Germany, the influential astronomer and printer Peter Apian produced the Astronomicum Caesareum: a printed and hand-coloured astronomical book visualising the Ptolemaic universe through the use of diagrams and wheelcharts, worthy of his imperial patron, Charles V. About 130 copies have survived to this day, with varying degrees of paper quality and level of decoration, and only eleven volumes are considered deluxe copies. We thoroughly analysed one deluxe volume held at the Fitzwilliam Museum, Cambridge, and compared the results with four (one deluxe and three standard) other copies from institutions in the UK. A non-invasive analytical protocol was applied, including extensive microscopy, fibre-optic reflectance spectroscopy (FORS), X-ray spectroscopy (XRF), macroscale XRF (MA-XRF) and Raman spectroscopy. The most interesting pages were chosen based on art-historical evidence and the variety of the colour palette, including on volvelles (wheelcharts) and coats of arms. Following a systematic approach, we analysed the same pages in each volume, gathering information on the colour palette in all the volumes. The type of paper and the presence of watermarks were also documented. A wide range of materials was identified in the five copies, including red, purple and yellow organic dyes, lead white, verdigris, vermilion, azurite, indigo, smalt, and lead–tin yellow. Mosaic gold was used to embellish certain paint passages in the deluxe volumes and metals (gold and silver) were applied on some pages. The comprehensive findings were essential to identify specific traits related to Apian's workshop, to differentiate deluxe from standard copies, to suggest an order of production of the copies, and to provide new information on this landmark book and more generally in an under-researched field of study. [ABSTRACT FROM AUTHOR]

In this study, we present a one‐pot synthetic approach for the preparation of metal oxide nanocomposites. Our investigation combines various analytical techniques, including FTIR, XRD, UV‐vis DRS, PL, XPS, SEM, EDX, and XANES, to comprehensively identify heterogeneous structures: SnO2‐CuO, CuO‐SnO2, NiO‐TiO2, and TiO2‐NiO. These metal oxide‐linked semiconductor solids serve as catalysts for dye photodegradation and exhibit remarkable biological activity. Our research is centered on exploring the photocatalytic potential of SnO2‐CuO nanocomposites while emphasizing the optimization of their photocatalytic and biological activities. This optimization is achieved through the careful incorporation of an ideal quantity of SnO2, as confirmed by EDX data, which reveals the composition as follows: O: 78.58 weight percent (0.525 keV), Cu: 12.61 weight percent (0.954 keV), and Sn: 8.81 weight percent (0.400 keV). Notably, under direct sunlight irradiation, the degradation efficiency of Rhodamine B dye surpasses that of pristine CuO, SnO2, TiO2, and NiO nanoparticles. Additionally, we explore the antimicrobial properties of these prepared samples at varying concentrations (50, 100, and 150 μl) against the pathogenic bacterium Staphylococcus aureus. Our findings highlight their effectiveness as antimicrobial agents. This research offers a promising method for developing highly active metal‐oxide‐linked nanomaterials, suitable for efficiently removing organic dye contaminants from water systems and showing great potential in antimicrobial applications. [ABSTRACT FROM AUTHOR]

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

Azo compounds find use in many areas of science, displaying crucial properties for important applications as photoconductive organic pigments, fluorescent quenchers, paints, cosmetics, inks, and in the large and valuable dye industry. Due to the unstable intermediates, and the exothermic and fast reactions used in their synthesis, high value azo compounds are excellent candidates for continuous flow manufacturing. This comprehensive review covers the progress made to date on developing continuous flow systems for azo synthesis and reflects on the main challenges still to be addressed, including scale up, conversion, product purity, and environmental impact. The further development of integrated continuous flow processes has the potential to help tackle these challenges and deliver improved methods for azo compound generation. [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]

A concise and efficient synthetic protocol for the synthesis of furan-based bis-stilbene derivatives (BPBFCz1) was described, which is a very promising organic laser dye. Starting with 4,4'-diethynylbiphenyl, BPBFCz1 was prepared with a total yield of 40% through a three-step classical reaction of Sonogashira Coupling, intramolecular cyclization of 2-alkynyl phenol, and Buchwald Hartwig cross-coupling. The crystal structure of BPBFCz1 was presented for the first time. The synthesis strategy was applied to the synthesis of other three materials with similar structure and the yields of 28.6–36.6% were obtained. [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]

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

This work presents a comprehensive investigation of novel organic dyes MD‐1‐2 as active acid and base co‐sensitizers in dye‐sensitized solar cells (DSSCs), using well‐known Ru(II)‐based N3 dyes. These co‐sensitizers contain a triphenylamine ring as a donor scaffold linked with an electron‐withdrawing cyanopyridyl and cyano benzoic acid acceptor for MD‐1‐2. In this study, we demonstrated the significant impact of base dyes with pyridine anchoring units on the photovoltaic parameters of N3‐sensitized devices. This methodology takes advantage of the ability of carboxyl and pyridyl moieties to interact with the Brønsted acid and Lewis acid sites on TiO2 surfaces, respectively. By reducing competition between dyes for surface binding, dye packing density on the TiO2 is enhanced while electron recombination is minimized, leading to higher photovoltage. Furthermore, the influence of varying sensitizer/co‐sensitizer ratios was comprehensively studied. Outcomes showed devices made using co‐sensitizer MD‐1‐2 with sensitizer N3 at all relative concentrations surpassed those with only N3. Importantly, the co‐sensitized devices that were made utilizing 0.3 mM acid–base MD‐1 and N3 sensitizer had the greatest solar energy capacity. It had a power conversion efficiency of 10.35%, a short‐circuit current density of 20.01 mA·cm−2, and an open‐circuit voltage of 752 mV. The results provide fresh insight into optimizing devices to create DSSCs with improved efficiency by choosing acceptable co‐sensitizers at suitable concentrations. [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]

Borophene is an emerging two-dimensional material exhibiting exceptional piezocatalytic activity under the influence of ultrasonic vibrations, as exemplified herein by the decomposition of highly stable organic dyes in water. After 6 minutes of exposure, borophene sheets converted up to 92 percent of a mixture of dye molecules at room temperature. [ABSTRACT FROM AUTHOR]

The addition of PnBu3 to o-substituted dianiline squaraine dyes leads to bench stable ylides. Exposure to a metal analyte in solution, results in PIII abstraction and rapid disruption of the ylide conjugation to promote reversion back to the squaraine dye giving an immediate turn-on colorimetric response. The stoichiometric sensitivity and accessibility of these chemodosimeters constitute effective organic dyes for trace transition metal detection. [ABSTRACT FROM AUTHOR]

Although second near‐infrared (NIR‐II, 1000–1500 nm) light has attracted considerable attention, especially for life sciences applications, the development of organic dyes with NIR‐II absorption remains a formidable challenge. Herein we report the design, synthesis, and electronic properties of 20π‐electron antiaromatic benziphthalocyanines (BPcs) that exhibit intense absorption bands in the NIR region. The strong, low‐energy absorption of the antiaromatic BPcs is attributed to electric‐dipole‐allowed HOMO‐LUMO transitions with narrow band gaps, enabled by the reduced structural symmetry of BPc compared with regular porphyrins and phthalocyanines. The combination of peripheral substituents and a central metal decreases the HOMO‐LUMO energy gaps, leading to the extension of the absorption bands into the NIR‐II region (reaching 1100 nm) under reductive conditions. [ABSTRACT FROM AUTHOR]

Advances in electronics and medical diagnostics have made organic dyes extremely popular as key functional materials. From a practical viewpoint, it is necessary to assess the spectroscopic and physicochemical properties of newly designed dyes. In this context, the condensation of 1,3-dimethylbarbituric acid with electron-rich alkylaminobenzaldehyde derivatives has been described, resulting in a series of merocyanine-type dyes. These dyes exhibit intense blue-light absorption but weak fluorescence. An electron-donating alkylamino group at position C4 is responsible for the solvatochromic behavior of the dyes since the lone electron pair of the nitrogen atom is variably delocalized toward the barbituric ring, which exhibits electron-withdrawing properties. This was elucidated, taking into account the different geometry of the amino group. The intramolecular charge transfer in the molecules is responsible for the relatively high redshift in absorption and fluorescence spectra. Additionally, an increase in solvent polarity moves the absorption and fluorescence to lower energy regions. The observed solvatochromism is discussed in terms of the four-parameter Catalán solvent polarity scale. The differences in the behavior of the dyes were quantified with the aid of time-dependent density functional theory calculations. The obtained results made it possible to find regularities linking the basic spectroscopic properties of the compounds with their chemical structure. This is important in the targeted search for new, practically important dyes. [ABSTRACT FROM AUTHOR]

Bimetallic nanoparticles with synergistic effects revealed much higher catalytic activity than respective monometallic materials. This review describes bimetallic nanoparticles, especially silver nanoparticles, combined with the other transition elements, such as Ag−Fe, Ag−Co, Ag−Ni, and Ag−Cu, as an enhanced catalytically active material. The coverage is given to the various methods of preparation, in which factors responsible for different structures of bimetallic nanoparticles are thoroughly discussed. Lastly, we explore the use of bimetallic nanoparticles as a catalyst for the degradation of numerous organic pollutants that contribute to water pollution. [ABSTRACT FROM AUTHOR]

It is necessary to develop methods for rapid degradation of untreated waterborne contaminants due to their serious impact on the environment and human health. Here, we proposed a rapid and efficient microplasma electrochemistry (MIPEC) method for organic dye and antibiotic degradation. The atmospheric-pressure plasma acted as the anode and it could generate reactive radicals for rapid and complete degradation of rhodamine B (RhB) in about 6 min, which is one of the fastest methods to our knowledge. Similarly, the degradation of ciprofloxacin (CIP) has also been achieved. This method with mild and convenient operation conditions could be applied in a wide pH range due to the unique properties of the plasma anode, unrestricted by the pH of wastewater. The mechanism study revealed that more reactive species could be generated at the plasma anode than at the cathode, leading to a faster reaction rate at the anode side and the presence of oxygen could also accelerate the generation of reactive species. Besides, the MIPEC method can be used to treat a variety of dyes separately and together in minutes in different water bodies, making it a universal method suitable for treating different dyes in wastewater. This work provides a rapid and efficient method for waterborne contaminant degradation without any secondary pollution and need for post treatment, and also broadens the application field of the MIPEC method. [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]

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]

A series of new granular carbonaceous adsorbents was prepared via single-stage physical and chemical activation of walnut shells. Their suitability for removing various types of organic pollutants (represented by dyes, surfactants and water-soluble polymers) from the liquid phase was assessed. The activation of the precursor was carried out with CO2 and H3PO4 using conventional heating. Activated biocarbons were characterized in terms of chemical composition, acidic–basic nature of the surface, textural and electrokinetic properties as well as thermal stability. Depending on the type of activating agent used during the activation procedure, the obtained biocarbons differed in terms of specific surface area (from 401 to 1361 m2/g) and the type of porous structure produced (microporosity contribution in the range of 45–75%). Adsorption tests proved that the effectiveness of removing organic pollutants from the liquid phase depended to a large extent on the type of prepared adsorbent as well as the chemical nature and the molecular size of the adsorbate used. The chemically activated sample showed greater removal efficiency in relation to all tested pollutants. Its maximum adsorption capacity for methylene blue, poly(acrylic acid), poly(ethylene glycol) and Triton X-100 reached the levels of 247.1, 680.9, 38.5 and 61.8 mg/g, respectively. [ABSTRACT FROM AUTHOR]

Herein, we have designed polyfunctional materials of d10‐configuration Cd (II) "Cd‐CP." The coordination polymer Cd‐CP was synthesized using benzene‐1,4‐dicarboxylic acid and 3,5‐diaminotriazole via solvothermal reaction. The Cd‐CP has been fully characterized by using single X‐ray crystallography, thermogravimetric analysis (TGA), Fourier transform–infrared (FT‐IR) spectroscopy, Raman spectroscopy, scanning electron microscopy (SEM), powder X‐ray diffraction (PXRD), and Brunauer–Emmett–Teller (BET) analysis. Single crystal X‐ray crystallography revealed that the CP‐Cd crystallized in triclinic space group P – 1 with the chemical composition [(BDC)(DAT)2Cd2Cl] (CH3)2 NH2+ · H2O. The present study investigated the impact of different reaction parameters, including the concentration of MG, the dosage of catalyst, and the duration of irradiation, on the outcome demonstrating a high level of photocatalytic efficacy at 99.19% under visible light irradiation. The obtained kinetic data exhibited conformity with a pseudo‐first‐order model, indicating that the rate‐determining step is likely to be photo‐absorption. The value of the apparent rate constant was found to be 0.019 min−1 for 50 mg L−1, 0.016 min−1 for 100 mg L−1, and 0.015 min−1 for 150 mg L−1 MG concentration. The corresponding half‐life time was found to be 36.44, 43.31, and 46.20 min with values of correlation coefficient (R2) as 0.99, 0.93, and 0.98, respectively. Moreover, a trapping experiment was conducted to demonstrate that hydroxy radicals (•OH) are the principal reactive oxygen species (ROS) responsible for the degradation of MG. The results of the total organic carbon (TOC) study indicated a mineralization value of around 89%, suggesting that the dye has been completely degraded into non‐toxic by‐products such as carbon dioxide (CO2) and water (H2O). [ABSTRACT FROM AUTHOR]

Organic dyes are widely used in many important areas, but they also bring many issues for water pollution. To address the above issues, a reconstructed kaolinite hybrid compound (γ-AlOOH@A-Kaol) was obtained from raw kaolinite (Kaol) in this work. The product was then characterized by X-ray diffraction (XRD), Fourier-transform infrared (ATR-FTIR), Brunauer-Emmett-Teller (BET), and scanning electron microscopy (SEM), and the absorption properties of γ-AlOOH@A-Kaol for congo red were further studied. The results demonstrated that flower-like γ-AlOOH with nanolamellae were uniformly loaded on the surface of acid-treated Kaol with a porous structure (A-Kaol). In addition, the surface area (36.5 m2/g), pore volume (0.146 cm3/g), and pore size (13.0 nm) of γ-AlOOH@A-Kaol were different from those of A-Kaol (127.4 m2/g, 0.127 cm3/g, and 4.28 nm, respectively) and γ-AlOOH (34.1 m2/g, 0.315 cm3/g, and 21.5 nm, respectively). The unique structure could significantly enhance the sorption capacity for congo red, which could exceed 1000 mg/g. The reasons may be ascribed to the abundant groups of -OH, large specific surface area, and porous structure of γ-AlOOH@A-Kaol. This work provides an efficient route for comprehensive utilization and production of Kaol-based compound materials that could be used in the field of environmental conservation. [ABSTRACT FROM AUTHOR]

The qualitative impact of pollutants on water quality is mainly related to their nature and their concentration, but in any case, they determine a strong impact on the involved ecosystems. In particular, refractory organic compounds represent a critical challenge, and several degradation processes have been studied and developed for their removal. Among them, heterogeneous Fenton treatment is a promising technology for wastewater and liquid waste remediation. Here, we have developed mono- and bimetallic formulations based on Co, Cu, Fe, and Mn, which were investigated for the degradation of three model organic dyes (methylene blue, rhodamine B, and malachite green). The treated samples were then analyzed by means of UV-vis spectrophotometry techniques. Bimetallic iron-based materials achieved almost complete degradation of all three model molecules in very short time. The Mn-Fe catalyst resulted in the best formulation with an almost complete degradation of methylene blue and malachite green at pH 5 in 5 min and of rhodamine B at pH 3 in 30 min. The results suggest that these formulations can be applied for the treatment of a broad range of liquid wastes comprising complex and variable organic pollutants. The investigated catalysts are extremely promising when compared to other systems reported in the literature. [ABSTRACT FROM AUTHOR]

A new amphiphilic azo‐functionalized polyhedral oligomeric silsesquioxane (POSS) derivative was synthesized by functionalizing octa(3‐aminopropyl)silsesquioxane (OAS‐POSS) with 4‐((4‐(dodecyloxy)phenyl)diazenyl)benzoic acid, affording a hydrophilic amino POSS head and hydrophobic dodecyl tail with a diphenyl‐azo connector. Prepared amphiphilic azo‐functionalized POSS (azo‐POSS) exhibited high ability for encapsulation and transferring cationic dyes into the organic phase by vigorously mixing with aqueous solutions of each dye. The photo‐controlled encapsulating properties of the synthesized phase transfer reagent was studied using cationic dyes, such as methylene blue (MB), crystal violet (CV) and thymol blue in acidic conditions. Results showed more than 95 % encapsulation of MB. However, no considerable encapsulation was shown in the case of anionic dyes such as eriochrome black T (EBT) and thymol blue in alkaline solutions. By trans/cis isomerization of the azo moiety of the phase transfer reagent by UV irradiation (365 nm), the amount of dye encapsulation was decreased, which could be attributed to the formation of cis isomer that led to the folding of the dodecyl alkyl tail on the POSS moiety, and therefore prevent to lay the 3‐aminopropyl moieties of POSS head to the water/DCM interface to adsorb and encapsulate MB molecules. [ABSTRACT FROM AUTHOR]

The results of evaluating the adsorption and fluorescent properties of azolotriazine compounds and phases based on cadmium sulfide quantum dots in vapors of volatile organic compounds (biomarkers of living systems) are considered. The adsorption properties of phases based on organic dyes and encapsulated semiconductors towards vapors of alcohols, ketones, amines, acids, ammonia, and aldehydes are investigated using direct high-sensitivity piezoelectric quartz microweighing. The spectral properties and their variations in analyte vapors are investigated using various spectroscopy methods (absorption, photoluminescence). The research results are compared, and the potential for optimizing this stage is assessed. It is proposed to evaluate the consistency of methods for predicting changes in fluorescent properties in test systems for volatile organic compounds using the Kendall coefficient of concordance, W. The highest level of agreement (W = 0.89) was observed between the methods of spectrofluorimetry and direct vapor microweighing upon adsorption on phases being potential fillers of test systems. A correlation between the results obtained by different fluorescence methods (visual plate test systems and fluorimetry of phases on paper substrates) is 0.80, which confirms a high degree of consistency in assessments using them in the degree of interaction between the analytes and organic, combined fluorochromes. The methods closely related in the nature of the analytical response do not exhibit better agreement than the method of direct vapor microweighing on microphases of fluorimetric reagents of different nature (cadmium sulfide quantum dots/chitosan, organic azolotriazine compounds, mixed phases). This, in turn, enables the selection of simpler, more available, and more rapid methods and means of analysis in routine experiments. [ABSTRACT FROM AUTHOR]

Among other photovoltaic techniques including perovskite solar cells and organic solar cells, dye-sensitized solar cells (DSSCs) are considered to be a potential alternative to conventional silicon solar cells. Porphyrins are promising dyes with the properties of easy modification and superior light-harvesting capability. However, porphyrin dyes still suffer from a number of unfavorable aspects, which need to be addressed in order to improve the photovoltaic performance. This feature article briefly summarizes the recent progress in improving the Voc and Jsc of porphyrin-based DSSCs in terms of molecular engineering by modifying the porphyrin macrocycle, donor and acceptor moieties of the porphyrin dyes, coadsorption of the porphrin dyes with bulky coadsorbents like chenodeoxycholic acid (CDCA), and cosensitization of the porphyrin dyes with metal-free organic dyes. Notably, concerted companion (CC) dyes are described in detail, which have been constructed by linking a porphyrin dye subunit and a metal-free organic dye subunit with flexible alkoxy chains to achieve panchromatic absorption and concerted enhancement of Voc and Jsc. In one sentence, this article is expected to provide further insights into the development of high performance DSSCs through the design and syntheses of efficient porphyrin dyes and CC dyes in combination with device optimization to achieve simultaneously elevated Voc and Jsc, which may inspire and promote further progress in the commercialization of the DSSCs. [ABSTRACT FROM AUTHOR]

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

This work demonstrated enhanced adsorption capabilities of lignin nanoparticles (LNPs) synthesized via a straightforward hydrotropic method compared to pristine lignin (PL) powder for removing methylene blue dye from aqueous solutions. Kraft lignin was used as a precursor and p-toluenesulfonic acid as the hydrotrope to produce spherical LNPs with ~ 200 nm diameter. Extensive characterization by SEM, AFM, DLS, zeta potential, and BET verified successful fabrication of microporous LNPs with fourfold higher specific surface area (14.9 m2/g) compared to PL (3.4 m2/g). Significantly reduced particle agglomeration and rearranged surface chemistry (zeta potential of −13.3 mV) arising from the self-assembly of lignin fractions under hydrotropic conditions enabled the application of LNPs and superior adsorbents compared to PL. Batch adsorption experiments exhibited up to 14 times higher methylene blue removal capacity, from 20.74 for PL to 127.91 mg/g for LNPs, and ultrafast equilibrium uptake within 3 min for LNPs compared to 10 min for PL. Kinetic modeling based on pseudo-first-order and pseudo-second-order equations revealed chemisorption as the predominant mechanism, with a rate constant of 0.032825 g/mg·h for LNPs—over an order of magnitude higher than PL (0.07125 g/mg·h). Isotherm modeling indicated Langmuir monolayer adsorption behavior on relatively uniform lignin surface functional groups. The substantially augmented adsorption performance of LNPs arose from the increased surface area and abundance of surface functional groups, providing greater accessibility of chemically active binding sites for rapid dye uptake. Overall, this work demonstrates that tailoring lignin nanoparticle structure and surface chemistry via scalable hydrotropic synthesis is a simple and sustainable approach for producing highly efficient lignin-based nano-adsorbents for organic dye removal from industrial wastewater. [ABSTRACT FROM AUTHOR]

STED nanoscopy allows for the direct observation of dynamic processes in living cells and tissues with diffraction-unlimited resolution. Although fluorescent proteins can be used for STED imaging, these labels are often outperformed in photostability by organic fluorescent dyes. This feature is especially crucial for time-lapse imaging. Unlike fluorescent proteins, organic fluorophores cannot be genetically fused to a target protein but require different labeling strategies. To achieve simultaneous imaging of more than one protein in the interior of the cell with organic fluorophores, bioorthogonal labeling techniques and cell-permeable dyes are needed. In addition, the fluorophores should preferentially emit in the red spectral range to reduce the potential phototoxic effects that can be induced by the STED light, which further restricts the choice of suitable markers. In this work, we selected five different cell-permeable organic dyes that fulfill all of the above requirements and applied them for SPIEDAC click labeling inside living cells. By combining click-chemistry-based protein labeling with other orthogonal and highly specific labeling methods, we demonstrate two-color STED imaging of different target structures in living specimens using different dye pairs. The excellent photostability of the dyes enables STED imaging for up to 60 frames, allowing the observation of dynamic processes in living cells over extended time periods at super-resolution. [ABSTRACT FROM AUTHOR]

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

The preparation of metallic nanoparticles using green synthetic approaches and its application toward the efficient degradation of environmentally hazardous dyes constitutes an attractive alternative to currently employed methods. In the current report, the green synthesis of silver nanoparticles (AgNPs) was successfully achieved using Actinidia deliciosa (kiwifruit) peel aqueous extract as a bioreducing agent under optimized synthesis conditions. The experimental parameters were optimized in terms of reactant ratio, reaction temperature, and reaction time. The biogenic nanoparticles exhibited SPR absorption band at λmax 480 nm. Transmission electron microscopy (TEM) and scanning electron microscopy (SEM) images revealed quasispherical monodisperse nanoparticles which were 36 nm in diameter. The hydrodynamic diameter of the nanoparticles was 106 nm as determined by dynamic light scattering, and the highly negative ζ-potential (−34 mV) supported its superior colloidal stability. Energy dispersive X-ray confirmed that silver is a major constituent of the nanoparticles. X-ray diffraction (XRD) diffractograms confirmed the crystallinity of the nanoparticles and its face-centered cubic (fcc) lattice structure. The functional groups in the plant's phytochemicals facilitating the reduction of Ag+ ions and stabilization of the formed AgNPs were identified by fourier transform infrared (FTIR) spectroscopy. In specific, the bands in the FTIR spectra at 3,412, 1,618, 1,419, and 1,237 cm−1 suggested the presence of phenolic compounds. Phytochemical analysis by colorimetric assays revealed that the kiwifruit peel extract was rich in phenolic compounds. When evaluated in the catalytic degradation of organic dyes, the biosynthesized AgNPs induced instant and complete discoloration of the methylene blue dye when 1.6 mg of nanoparticles was used. At a lower dose of AgNPs (0.4 mg), 80% degradation of the dye occurred after 3 hr of treatment. The degradation reaction followed second-order kinetics with a rate constant of 0.01083 mM−1s−1. The current study highlights the immense potential of the prepared nanoparticles as efficient catalysts for the degradation of hazardous organic dyes such as methylene blue and presents an intriguing argument for investigating the catalytic efficiency of the biogenic AgNPs for the degradation of other structurally different dye pollutants. [ABSTRACT FROM AUTHOR]

AbstractReaction of Mn(OAc)2·4H2O with pentaerythritol (H4peol) in the presence of NaSCN leads to formation of a 1-D coordination polymer (CP) based on Mn(II), [Mn(SCN)2(peol)]n (1, SCN− = thiocyanate), under solvothermal conditions. EA, FTIR, PXRD, SCXRD and TGA analyses were used to study the composition and phase purity of the Mn(II) coordination polymer. The degradation of alizarin was investigated using organic framework substances as degradation agents. The results showed that the maximum degradation value of 86.12% was achieved at 50 min. This study not only promotes the preparation of organic frameworks, but also provides a feasible solution for the effective degradation of alizarin. [ABSTRACT FROM AUTHOR]

The current study reports tailoring the electronic donor structures of organic dyes to modify their optical and nonlinear optical (NLO) response properties. Five (5) tri‐phenyl amine (TPA) based Donor‐π‐Acceptor (D‐π‐A) organic dyes with the codes ICAA1, ICAA2, ICAA3, ICAA4, and ICAA5 were designed and investigated for their optical and NLO properties using quantum chemical methods. Optical and NLO properties of these dyes were studied by CAM‐B3LYP method and 6‐311G* basis set. The focus has been on the impact of adding secondary donors and shifting their substitutions at ortho (o), meta (m) and para (p) positions. Among all designed compounds, ICAA4 showed the highest amplitude of average third‐order NLO polarizability <γ>, which is calculated to be 1316 × 10−36 esu. Time‐dependent Density Functional Theory (TD‐DFT) method was used to determine how a change in the position of the donor affected the excitation energy (Eg) and NLO response properties. The findings showed that changing the position of the secondary donor results in a red shift among absorption spectra as well as the increase in their NLO responses. Complete process of intramolecular charge transfer (ICT) has been investigated in terms of different optical parameters such as frontier molecular orbitals (FMOs), molecular electrostatic potentials (MEPs), transition density matrix (TDMs), density of states (DOS), electron density difference (EDD), and natural bond orbital (NBO) analysis. Our calculations for study of ICT process indicate that p‐position of methoxy group performs better among all other positions and even it has better NLO response properties than the compound with three collective methoxy groups. The calculated Voc values of all designed molecules range from 1.09 to 1.30, all of them are positive while their ΔGinject is found to be in the range of −0.87 to −1.79 eV indicating their decent potential for photovoltaic applications. The studied optical, NLO and photovoltaic parameters illustrated that ICAA1 to ICAA5 are appropriate molecules not only for NLO applications but also for efficient photovoltaic purposes. [ABSTRACT FROM AUTHOR]

Sensitive detection of shortwave infrared (SWIR) light using organic dyes will be a significant advance toward many applications in industry and research. Furthermore, from a fabrication and optimization view, photogeneration of charges in diodes consisting of a single dye layer will be highly attractive. However, SWIR dyes are scarce and organic photodiodes usually utilize a donor–acceptor materials combination to split excitons into charges. Here, it is demonstrated that single‐component layers of several SWIR squaraine dyes operate as efficient photodetectors, with peak external quantum efficiency > 40% beyond 1000 nm and sensitivity out to 1300 nm. Photocurrents show a superlinear dependence on reverse bias. It is shown that this results from a field‐assisted exciton dissociation mechanism, and not from field‐dependent charge injection or extraction. SWIR photodiodes are combined with organic light‐emitting diodes to fabricate upconversion photodetectors – devices that convert SWIR photons directly into visible light. Upconverters are characterized by a low turn‐on voltage (1.5 V) and a high luminance contrast (on‐off ratio 16 000) and SWIR‐to‐visible (λ = 575 nm) photon conversion efficiency (1.85%). Upconversion photodetectors emerge as a promising alternative to the current inorganic‐based imaging technology. [ABSTRACT FROM AUTHOR]

Herein, the surface of pyrolyzed coconut coir (PCC) dust has been functionalized using atmospheric plasma under non‐equilibrium conditions without utilizing vacuum chambers. The reactive species present in the plasma such as, molecular ions, electrons, and radicals interact with PCC's surface, leading to the introduction of epoxy, carbonyl and amino functional groups on carbon surface. The resulting plasma functionalized carbon (PFC) material was characterized using several advanced material characterization techniques, including PXRD, FTIR, XPS, N2 BET specific surface area, SEM and TEM imaging techniques, etc. Moreover, it has been used in diverse applications in toxic gas removal (CO2, CO, NOx), fluoride (F−) removal from drinking water and cationic organic dye (methylene blue–MB) removal. The reported method for synthesis of functional carbon introduces a platform technology for low carbon footprint, green synthesis of advanced functional materials. [ABSTRACT FROM AUTHOR]

The research article introduces the unexplored synergistic effect of amorphous titanium dioxide and phosphorus-doped carbon nanodot hybrid [C-TiO2(am)] for the ultrafast adsorption of methylene blue and crystal violet dyes. The hybrid eliminates 98% of methylene blue dye (MB) at a concentration of 32 mg/L and 96% of crystal violet dye at a concentration of 62 mg/L from the aqueous solution within 5 min of contact time at ambient temperature. The incorporation of phosphorus-doped carbon nanodot in amorphous TiO2 modifies the oxygen vacancy, which enhances the material's affinity for organic dyes like MB and crystal violet. The significance of defects on the adsorption efficiency of C-TiO2 (am) is obtained and compared with that of amorphous titanium dioxide [TiO2(am)] and the crystalline phase of hybrid (C-TiO2). The dye removal percentages of TiO2 (am) and C-TiO2 are ca.3% and ca.32%, respectively, which is feeble compared to the dye removal percentage of C-TiO2 (am) (ca. 98%). The possible mechanism of organic dye adsorption of C-TiO2 (am) is derived through the detailed discussion of porosity, morphology, functional groups, and chemical compositions. The impact of temperature on dye adsorption and removal rate is determined using non-linear regression analysis. The remarkable characteristic adsorption features of C-TiO2 (am) suggest that it can be considered as a new potential adsorbent for water purification. The remarkable characteristic adsorption features of C-TiO2 (am) suggest that it can be considered as a new potential adsorbent for water purification. [ABSTRACT FROM AUTHOR]

This research investigates characterization of low lying excitations of newly designed organic dyes for their local excited and charge transfer-related molecular switching attributes such as donor-acceptor relations against the carbazole bridge. The eight new dyes, having 4 symmetrical (Syn-A-D) and 4 antisymmetric (Anti-A-D) arrangements showed how the push-pull effect can operate to create the charge transfer phenomenon. Their absorption energies (E) for Syn dyes ranged from 2.98 eV to 4.07 eV, with corresponding wavelengths (λmax) ranging from 304 nm to 415 nm. While for their Anti arrangements, it ranged from 1.62 eV to 3.99 eV, with corresponding λmax values as 310-617 nm. Syn-C1 with an ionization potential (IP) of 6.59 eV and an electron affinity (EA) of 2.04 eV can be predicted to be more chemically stable compared to Anti-C2 with an IP of 5.16 eV and an EA of 3.86 eV. Syn-C also has the highest Voc (3.24 eV) and Pmax (22.35 W), indicating that it has the potential to be more chemically stable as compared to the other dyes. The findings of this research contributed to a better understanding of the molecular switching attributes of carbazole-based organic dyes, which could have implications for various applications, including optoelectronics and energy conversion devices. This research explores on characterizing low lying excitations of newly designed organic dyes for their local excited and charge transfer related molecular switching attributes as donor-acceptor relations against the carbazole bridge. The eight new dyes, having 4 symmetrical (Syn-A-D) and 4 antisymmetric (Anti-A-D) arrangements showed that how the push-pull effect can operate to create the charge transfer phenomenon. [ABSTRACT FROM AUTHOR]

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

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]

The current study employed the hydrothermal approach to graft chitosan functionalized-SiO2 nanoparticles with an aromatic aldehyde (salicylaldehyde, SA) to obtain an organic–inorganic nanohybrid composite of salicylaldehyde-based chitosan Schiff base/SiO2 (CTS-SA/SiO2) for uptake of an acidic azo dye (acid red 88, AR88) from aqueous media. The effects of A: CTS-SA/SiO2 dose (0.02–0.1 g), B: pH (4–10), and C: time (10–90 min) on the adsorption performance of CTS-SA/SiO2 towards AR88 were studied systematically by the Box–Behnken Design (BBD). The CTS-SA/SiO2 dosage, pH, and contact time resulted in maximum dye elimination (76.46%) of AR88, according to the results of the BBD model. These variables were 0.093 g of CTS-SA/SiO2, pH 4.5, and 87.4 min. The pseudo-second order and Langmuir isotherm provide an account of the experimental results for AR88 adsorption by CTS-SA/SiO2. The calculated maximum Langmuir adsorption capacity for CTS-SA/SiO2 is equal to 184.2 mg/g. The high adsorption of AR88 onto the CTS-SA/SiO2 can be mainly ascribed to electrostatic forces between the protonated CTS-SA/SiO2 and the AR88 anions, along with n–π, π–π, and H-bond interactions. This research demonstrates that CTS-SA/SiO2 has promising potential as an adsorbent for organic dye removal from water systems. [ABSTRACT FROM AUTHOR]

A highly flexible and cost-effective copper tape decorated with silver nanoparticles (Cu-TAg) has been developed for surface-enhanced Raman spectroscopy (SERS) sensing of multi-hazardous environmental pollutants. Highly ordered and spherical-shaped silver nanoarrays have been fabricated using a low-cost thermal evaporation method. The structural, morphological, and optical properties of Cu-TAg sensors have been studied and correlated to the corresponding SERS performances. The size of nanoparticles has been successively tuned by varying the deposition time from 5 to 25 s. The nanoparticle sizes were enhanced with an increase in the evaporation time. SERS investigations have revealed that the sensing potential is subsequently improved with an increase in deposition time up to 10 s and then deteriorates with further increase in Ag deposition. The highest SERS activity was acquired for an optimum size of ~ 37 nm; further simulation studies confirmed this observation. Moreover, Cu-TAg sensors exhibited high sensitivity, reproducibility, and recycling characteristics to be used as excellent chemo-sensors. The lower detection limit estimation revealed that it can sense even in the pico-molar range for sensing of rhodamine 6G and methylene blue. The estimated enhancement factor of the sensor is found to be 9.4 × 107. Molecular-specific sensing of a wide range of pollutants such as rhodamine 6G, alizarin red, methylene blue, butylated hydroxy anisole, and penicillin–streptomycin is demonstrated with high efficiencies for micromolar spiked samples. Copper tape functionalized with Ag arrays thus demonstrated to be a promising candidate for low-cost and reusable chemo-sensors for environmental remediation applications. [ABSTRACT FROM AUTHOR]

Industrial wastewater has detrimental impacts on aquatic ecosystems and the environment. Among the significant contributors to water pollution are organic dyes, which are frequently released into untreated outflow water. Hence, effective degradation of these dyes and their derivatives using heterogeneous photocatalysts is imperative before discharge. In this study, we successfully synthesized a novel nanocomposite by g-C3N4 coupled with TiO2 and decorated it with Ni followed by cost-effective methods. Immaculate g-C3N4 coupled with TiO2 (TiO2+) and modified with nickel (Ni+) was synthesized through melamine calcination followed by hydrothermal processing. Characterization through diverse electro-analytical techniques, including X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FT-IR), and Brunauer-Emmett-Teller (BET), was conducted on the novel photocatalysts. XRD results revealed their high crystallinity, enhanced through modification. The effectiveness of these photocatalysts in degrading the organic dye methylene blue (MB) under UV–Vis light was thoroughly investigated. It also investigated how the results were affected by important factors involving contact time, dye and photocatalyst dosages, pH, and reusability. Among the photocatalysts, the composite g-C3N4-TiO2s, decorated with Ni, exhibited exceptional performance, displaying substantial degradation efficacy. The findings demonstrate that the novel g-C3N4-based photocatalysts are highly efficient at degrading organic dyes, so the work is expected to be the best contribution in the photodegradation study of organic contaminants. [ABSTRACT FROM AUTHOR]