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An efficient removal of the photocatalysts used in the decontamination of water is crucial after its application beside its expected visible light sensitive activities. This study presents the synthesis of magnetically separable CuFe2O4 nanoparticles (CFNPs) with enhanced photoactivity under AM 1.5 G sunlight. A simple two-step process involving co-precipitation and hydrothermal treatment is employed, with subsequent annealing at temperatures from 200 °C to 1000 °C to synthesize the CFNPs. The characteristic features of the highest photoactive tetragonal phase of CFNP are confirmed by powder XRD studies with Rietveld refinement. This scheme strategically controls the growth of a highly photoactive tetragonal phase with predominant (224) facets over other less active facets in cubic CuFe2O4. Mott–Schottky analysis confirms the p -type semiconducting nature of CFNPs. A favourable direct optical band gap of 1.73 eV, as well as photoluminescence emission quenching for visible photons, show that the (224) oriented CFNPs are good photocatalysts in the visible spectrum with demonstrated organic dye degradations, including methylene blue and others. A density functional theory-based approach validates that the adsorption of such dye is thermodynamically more favourable on (224) facets of CuFe2O4 to facilitate the redox action by the excitons. [ABSTRACT FROM AUTHOR]

GaN is more stable than most metal oxide semiconductors for the photocatalytic degradation of organic pollutants in harsh conditions, while its catalytic efficiency has been difficult to be substantially improved. In this study, the tribocatalytic degradation of organic dyes by GaN nanoparticles has been investigated. Stimulated through magnetic stirring using homemade Teflon magnetic rotary disks in glass beakers, the GaN nanoparticles were found to induce negligible degradation in rhodamine B (RhB) and methyl orange (MO) solutions. Surprisingly, the degradation was greatly enhanced in beakers with Ti and Al2O3 coatings on their bottoms: 99.2% and 99.8% of the 20 mg/L RhB solutions were degraded in 3 h for the Ti and Al2O3 coatings, respectively, and 56% and 60.2% of the 20 mg/L MO solutions were degraded in 24 h for the Ti and Al2O3 coatings, respectively. Moreover, the MO molecules were only broken into smaller organic molecules for the Ti coating, while they were completely degraded for the Al2O3 coating. These findings are important for the catalytic degradation of organic pollutants by GaN in harsh environments and for achieving a better understanding of tribocatalysis as well. [ABSTRACT FROM AUTHOR]

The presented study was focused on the simple, eco-friendly synthesis of composite hydrogels of crosslinked carboxymethyl cellulose (CMC)/alginate (SA) with encapsulated g-C3N4 nanoparticles. The structural, textural, morphological, optical, and mechanical properties were determined using different methods. The encapsulation of g-C3N4 into CMC/SA copolymer resulted in the formation of composite hydrogels with a coherent structure, enhanced porosity, excellent photostability, and good adhesion. The ability of composite hydrogels to eliminate structurally different dyes with the same or opposite charge properties (cationic Methylene Blue and anionic Orange G and Remazol Brilliant Blue R) in both single- and binary-dye systems was examined through adsorption and photocatalytic reactions. The interactions between the dyes and g-C3N4 and the negatively charged CMC/SA copolymers had a notable influence on both the adsorption capacity and photodegradation efficiency of the prepared composites. Scavenger studies and leaching tests were conducted to gain insights into the primary reactive species and to assess the stability and long-term performance of the g-C3N4/CMC/SA beads. The commendable photocatalytic activity and excellent recyclability, coupled with the elimination of costly catalyst separation requirements, render the g-C3N4/CMC/SA composite hydrogels cost-effective and environmentally friendly materials, and strongly support their selection for tackling environmental pollution issues. [ABSTRACT FROM AUTHOR]

Iron oxide nanoparticles were synthesized by co-precipitation using three different iron salt stoichiometric mole ratios. Powder X-ray diffraction patterns revealed the inverse cubic spinel structure of magnetite iron oxide. Transmission electron microscopic images showed Fe3O4 nanoparticles with different shapes and average particle sizes of 5.48 nm for Fe3O4-1:2, 6.02 nm for Fe3O4-1.5:2, and 6.98 nm for Fe3O4-2:3 with an energy bandgap of 3.27 to 3.53 eV. The as-prepared Fe3O4 nanoparticles were used as photocatalysts to degrade brilliant green (BG), rhodamine B (RhB), indigo carmine (IC), and methyl red (MR) under visible light irradiation. The photocatalytic degradation efficiency of 80.4% was obtained from Fe3O4-1:2 for brilliant green, 61.5% from Fe3O4-1.5:2 for rhodamine B, and 77.9% and 73.9% from Fe3O4-2:3 for both indigo carmine and methyl red. This indicates that Fe3O4-2:3 is more efficient in the degradation of more than one dye. This study shows that brilliant green degrades most effectively at pH 9, rhodamine B degrades best at pH 6.5, and indigo carmine and methyl red degrade most efficiently at pH 3. Recyclability experiments showed that the Fe3O4 photocatalysts can be recycled four times and are photostable. [ABSTRACT FROM AUTHOR]

Organic photoluminescent materials with room‐temperature phosphorescence (RTP) are of great interest, yet achieving RTP in hydrogels faces challenges due to water‐quenching effects. In this study, a straightforward method is presented to achieve RTP hydrogel using a self‐healing and salt‐hardening hydrogel. The hydrogel is synthesized by polymerizing acrylic acid (AA) with diethylenetriamine (DETA) as the dynamic crosslinker. The poly(acrylic acid)/DETA hydrogel could achieve an afterglow lasting 1.6 s after soaking with NaBr solution. The salt‐enhanced hydrophobic aggregation of the hydrogel network promotes the clustering of carboxyl groups and oxygen atoms, resulting in a rigid environment that suppresses nonradioactive transitions and leads to the manifestation of RTP. Additionally, the dynamic association of AA‐DETA allows the freeze‐dried hydrogel powder to be blended with various hydrophobic dyes, leading to a remodelable hydrogel with delayed emission of multiple colors. In general, by combining salt‐hardening property with self‐healing property together, a RTP hydrogel platform that can be facilely loaded with various organic dyes is proposed. [ABSTRACT FROM AUTHOR]

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

Three new chromophores based on difluoroborondipyrromethene dyes (Bodipy‐1, Bodipy‐2, and Bodipy‐3) are used as precursors to prepare luminescent solar concentrators (LSC) based on poly‐acrylate, following a thermally activated polymerization involving lauryl methacrylate as monomer, ethyl glycol dimethacrylate as cross‐linking agent, and lauroyl peroxide as initiator. The new dyes exhibit typical BODIPY absorption and emission properties in dichloromethane fluid solution, assigned to the lower‐lying singlet π–π∗ level, which in the case of Bodipy‐2 and Bodipy‐3, both containing diamino‐substituted styryl subunits in their structure, has a strong charge transfer contribution. The LSCs obtained starting from each of the three Bodipys are interfaced to silicon photovoltaic (PV) cells, and the PV light‐to‐energy conversion efficiencies ηopt for the three systems are calculated. The results yield ηopt of 4.53% for LSC‐Bodipy‐1, 5.26% for LSC‐Bodipy‐2, and 8.23% for LSC‐Bodipy‐3. The optical efficiency for LSC‐Bodipy‐3 is a remarkable value among the LSC based on organic dyes. [ABSTRACT FROM AUTHOR]

The fields of biomedicine and catalysis have both shown a great deal of interest in copper oxide nanoparticles (CuONPs). Green synthesis methods are being frequently employed to develop highly active CuONPs. This research investigates the potential photocatalytic and antibacterial applications of two CuONPs that were synthesized utilizing extracts from Dillenia indica (D‐CuONPs) and Mikania micrantha (M‐CuONPs) leaves. Analysis using electron microscopy revealed that CuONPs are uniformly spherical and average size around 15 nm. The development of single‐phase CuONPs with a monoclinic structure is shown by X‐ray diffraction studies. The FTIR peaks at 695 cm−1 and 860 cm−1 represent a stretching of Cu−O, signifying the formation of CuO nanostructure. The EDX profiles stated that the CuONPs are correlated with compliantly intensified Cu and O signals. Under solar irradiation, around 90 % of congo red (CR) dye was degraded by both CuONPs in 120 min, with the rate constants of 0.0187 and 0.0174 min−1, respectively. Furthermore, CuONPs have excellent antibacterial activity against bacteria belonging to both Gram classes. Overall, CuONPs hold great potential for inhibiting the growth of pathogenic bacteria and for degrading organic dyes in the presence of sunlight. As such, they can be manufactured on a large scale using plant sources. [ABSTRACT FROM AUTHOR]

The combination of visible light, a renewable and green energy source, and rose bengal, a non‐toxic organic dye as a photoredox catalyst, is an easy and efficient method for synthesizing 3,4‐dihydropyrimidin‐2(1H)‐ones/thiones in EtOH at ambient temperature in very short reaction time. The present work offers simple operation, easy workup, rapid conversion, and excellent product yields, while accommodating a wide range of substrates. Rose bengal‐based photocatalytic approach permits foremost sustainability, which delivers economic and environmental rewards. [ABSTRACT FROM AUTHOR]

Industries persistently contribute to environmental pollution by releasing a multitude of harmful substances, including organic dyes, which represent a significant hazard to human health. As a result, the demand for effective adsorbents in wastewater treatment technology is steadily increasing so as to mitigate or eradicate these environmental risks. In response to this challenge, we have developed an advanced composite known as MOF-5/Cellulose aerogel, utilizing the Pampas plant as a natural material in the production of cellulose aerogel. Our investigation focused on analyzing the adsorption and flexibility characteristics of this novel composite for organic dye removal. Additionally, we conducted tests to assess the aerogel's reusability and determined that its absorption rate remained consistent, with the adsorption capacity of the MOF-5/cellulose aerogel composite only experiencing a marginal 5% reduction. Characterization of the material was conducted through XRD analysis, revealing the cubic structure of MOF aerogel particles under scanning electron microscopy. Our study unequivocally demonstrates the superior adsorption capabilities of the MOF-5/cellulose aerogel composite, particularly evident in its efficient removal of acid blue dye, as evaluated meticulously using UV–Vis spectrophotometric techniques. Notably, our findings revealed an impressive 96% absorption rate for the anionic dye under acidic pH conditions. Furthermore, the synthesized MOF-5/cellulose aerogel composite exhibited Langmuir isotherm behavior and followed pseudo-second-order kinetics during the absorption process. With its remarkable absorption efficiency, MOF-5/cellulose aerogel composites are poised to emerge as leading adsorbents for water purification and various other applications. [ABSTRACT FROM AUTHOR]

Mimicking the characteristics and achieving specific functions of biological systems is stirring but challenging. Generally, pigments in the commercial coating can only achieve a similarity in chromaticity, while cannot obtain a similarity in the solar reflective spectrum whose difficulty resides in simulating spectral characteristics simultaneously. Unfortunately, traditional organic pigments show poor weather and heat resistance. Herein, with the little difference in the color difference (ΔEab*), the high spectral similarity, as well as adjustable green peak and similar red edge slope compared with the common plants (pagoda tree leaf, etc.) in 400–2500 nm, is also attained. It is achieved by the interlayer confined organic pigment in Mg/Al‐layered double hydroxide (Mg/Al‐LDH) layers. The corresponding biomimetic leaf displays high hyperspectral performance with a spectral angle cosine of 0.9922 and heat resistance at 120 °C. The longer weather resistance than that of mechanical mixing is also demonstrated. The intercalated chromophores of sodium copper chlorophyllin in the Mg/Al‐LDH and the interlayer confinement of Mg/Al‐LDH contribute to the excellent performance. This work provides a green pigment and a biomimetic leaf requiring the same chromaticity and spectrum as green plants, filling the long‐term use demand gap for heat and weather‐resistant biomimetic vegetation. [ABSTRACT FROM AUTHOR]

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

To screen efficient organic dyes, six novel XY1b-based molecules are designed by modifying electron-assisted acceptors, and their electronic structure, optical properties and photovoltaic performances are evaluated in detail with density functional theory (DFT) and time-dependent DFT (TD-DFT) calculations coupled with the incoherent charge transfer model. Results show that benzoselenadiazole (BSD) and diketopyrrolopyrrole (DPP) are two best electron-assisted acceptors and replacing benzothiadiazole (BTD) with the BSD/DPP unit can redshift the maximum absorption peak by 13/67 nm. According to our estimation, the overall photoelectric conversion efficiency (PCE) of XY1b is as high as 13.09% with a Jsc of 16.261 mA·cm−2, Voc of 1.047 V and FF of 0.769, in good agreement with its measured value of 11.8 ± 0.2% (Jsc = 15.26 ± 0.18 mA·cm−2, Voc = 1.01 ± 0.003 V and FF = 76.3 ± 0.2%), verifying that the scheme proposed by us is reliable. With the same procedure, the predicted PCE values for dyes 1, 2 and 5 reach up to 18.00%, 15.95% and 27.37% respectively, indicating that these three dyes are potential efficient sensitisers and are worthy of further study by experiments. [ABSTRACT FROM AUTHOR]

Wood specimens were dyed by boiling them in the presence of walnut shells and dye to penetrate the dyestuff into the sample. Specimens prepared from Scots pine, oak, and beech woods were boiled separately in walnut shell, water, and NaOH environment, and the penetration of the dyestuff into the samples was ensured. Sodium hydroxide solution was preferred because it facilitates the dissolution of the hemicelluloses in the wood and the dyestuffs in the walnut shell. Alum was added in other samples to reveal the mordant effect on the adhesion of dyestuffs to wood. Thermogravimetric (TG) analysis revealed that wood degradation primarily occurs due to evaporation of free water at 50 to 120 ℃, followed by lignin and cellulose breakdown across a wide temperature range of 160 to 600 ℃. Treatment with NaOH and NaOH+alum notably reduced the peak temperatures in differential-thermogravimetric analysis by indicating an effect on lignin. This was supported by Fourier transform infrared analysis, particularly in the disappearance of carboxyl groups at 1710 cm-1 and significant decreases in peak intensities at 1027, 1247, 1315, and 1501 cm-1. Based on the findings, it was concluded that the dyed parts obtained can be used in the wooden toy industry. [ABSTRACT FROM AUTHOR]

Repurposing enzymes to catalyze non‐natural asymmetric transformations that are difficult to achieve using traditional chemical methods is of significant importance. Although radical C−O bond formation has emerged as a powerful approach for constructing oxygen‐containing compounds, controlling the stereochemistry poses a great challenge. Here we present the development of a dual bio‐/photo‐catalytic system comprising an ene‐reductase and an organic dye for achieving stereoselective lactonizations. By integrating directed evolution and photoinduced single electron oxidation, we repurposed engineered ene‐reductases to steer non‐natural radical C−O formations (one C−O bond for hydrolactonizations and lactonization‐alkylations while two C−O bonds for lactonization‐oxygenations). This dual catalysis gave a new approach to a diverse array of enantioenhanced 5‐ and 6‐membered lactones with vicinal stereocenters, part of which bears a quaternary stereocenter (up to 99 % enantiomeric excess, up to 12.9 : 1 diastereomeric ratio). Detailed mechanistic studies, including computational simulations, uncovered the synergistic effect of the enzyme and the externally added organophotoredox catalyst Rh6G. [ABSTRACT FROM AUTHOR]

Developing economical and high‐performing sensitizers is crucial in advancing dye‐sensitized solar cells (DSSCs) and optoelectronics. This research paper explores the potential of novel red light‐absorbing organic dyes based on Indolo[3,2‐b]carbazole (ICZ) as the donor applied in co‐sensitizer‐free DSSCs for breakthroughs in photovoltaic (PV) applications. DFT and TD‐DFT based computational methods were employed to calculate the conduction band levels, electron injection capabilities, and power conversion efficiency (PCE) of metal‐free organic dyes (ICZ1–ICZ9) having D‐A‐π‐A architecture. Comprehensive analyses included NBO, DOS, FMO, ICT, MEP, binding energy, and TDM analysis. Quantum chemical calculations of the structural, photochemical, and electrochemical properties, as well as the key parameters, reveals that all the designed dyes could be an excellent candidate for high‐efficiency DSSCs due the small energy gap (2.130–1.947 eV), longer wavelength absorption (759.47–520.63 nm), longer lifetimes (15.65–6.67 ns), a lower ΔGreg (0.29–0.14 eV), a significant dipole moment changes (31.489–16.195D), LHE (0.95‐0.46), the large qCT (0.962–0.689), small DCT (7.657, 4.897 Å), and VOC (1.13–0.86 eV). This quantum simulation showed that, when compared to reference D8, the photovoltaic dyes ICZ8, ICZ2, and ICZ7 are recognized as being eye‐catching. Furthermore, dye@(TiO2)9 cluster model results demonstrate promising prospects for enhancing the photovoltaic (PV) performance of ICZ1–ICZ9 dyes by electron injection and conduction band (CB) engineering. This study will help the experimentalists for developing ICZ‐based PVs as more efficient and sustainable energy solutions. [ABSTRACT FROM AUTHOR]

A honeycomb porous cadmium(II) metal–organic framework {[Cd(L)(H2O)] ⋅ NMP ⋅ 5H2O}n (1, H2L=1‐(4‐carboxyphenyl)‐1H‐pyrazole‐3‐carboxylic acid and NMP=1‐methyl‐2‐pyrrolidinone) was obtained using the solvothermal method. The luminescent molecules rhodamine B (RhB) and fluorescein (FL) were encapsulated in 1 using the immersion method to prepare RhB@1 and FL@1 dual emission composites. Additionally, a series of RhBx/FL1‐x@1 composites with varying luminescence properties were generated by altering the molar ratio of RhB to FL. Furthermore, the photoluminescence of RhB@1 and FL@1 was demonstrated to be caused by photoelectron transfer and fluorescence resonance energy transfer from 1 to the encapsulated guest module. Notably, RhB@1 showed the considerable improvement in fluorescence selectivity and detection limit (10−6 M) for metronidazole and dimetronidazole with remarkable recyclability. [ABSTRACT FROM AUTHOR]

Efficient photosensitizers are crucial for advancing solar energy conversion and storage technologies. In this study, we designed and synthesized a novel organic dye, denoted as YB6, for p‐type dye‐sensitized solar cells (p‐DSCs) and photoelectrochemical H2O2 production. YB6 features an extended conjugated π‐bridge derived from indacenodithieno[3,2‐b]thiophene and exhibits notable advantages: a two‐fold higher molar extinction coefficient at its main absorption peak and a broader absorption as compared to the PB6 dye. In p‐type dye‐sensitized NiO photoelectrochemical cells, the YB6‐based device demonstrated superior performance as compared to the PB6‐based device. It delivered nearly a 50 % higher H2O2 production over 5 hours. Furthermore, when fabricated into p‐DSCs, the YB6‐based device exhibited a 33 % higher power conversion efficiency. This enhancement is caused by suppressed charge recombination from the dye structure, which in turn may be traced to a larger thermodynamic up‐hill process for recombination losses in the YB6‐based system. [ABSTRACT FROM AUTHOR]

As excellent functional materials, the composite materials based on graphene and its derivatives (GNDs) have lots of important application values in the emerging fields such as solar energy conversion, and the exploration of electron (or energy) transfer properties of those composites is the key for revealing their further applications. In this review, femtosecond transient absorption spectroscopy (TAS) has been introduced as an essential technique to understand the carrier behaviors in GNDs composites, as well as the advancements of TAS. The specific examples of electron transport in various composite materials characterized by TAS are summarized and discussed, which consist of GNDs with semiconductor quantum dots (QDs), organic dyes, organic polymers, perovskites and other materials, respectively. This review provides a deep insight into the electron transfer (ET) kinetics of various GNDs composites from the perspective of TAS. [ABSTRACT FROM AUTHOR]

In this research, the alginate doped graphene oxide (GO)-Fe3O4-TiO2 photomagnetic nanocomposite was synthesised through a three-step method. For comparison, alginate-GO was also prepared. The synthesised materials were characterised through FTIR, XRD, TGA, SEM, EDX, and TEM techniques. The photomagnetic properties of the resultant nanocomposite were evaluated by VSM. Degradation of Malachite green as a dye pollutant was studied in the presence of alginate (Alg), Alg-GO, and Alg-GO-Fe3O4-TiO2 nanocomposite using a sonophotocatalysis technique. The results showed, that, Alg-GO-Fe3O4-TiO2 nanocomposite has high efficiency in the removal of Malachite green. Recycling experiments displayed that the degradation efficiency dropped only by 12%, after five successive runs. and makes it a promising catalyst for efficient degradation of dye pollutants in the practical applications. [ABSTRACT FROM AUTHOR]

Simple Summary: From Ancient Egypt to the present day, acquiring the color red in the art world has involved various methods. Over the centuries, these methods have included oxides, natural minerals, and organic dyes obtained from plants and insects. This study focuses on the Cochineal insect, which produces a natural red pigment called carmine. This pigment has been used in art for thousands of years, especially by indigenous cultures for textile dyes and paintings. During the Renaissance, artists valued carmine for its bright red tones. The study examines the history of the Cochineal insect, its role in art, and its modern perception. It also discusses famous artworks created with cochineal dyes and how these pigments have inspired artists. Paints obtained from insects are generally regarded as a natural and organic source, making them an environmentally friendly option. Incorporating insect-derived paints into artworks allows for the integration of an organic element sourced from nature. Furthermore, the use of these paints can help enrich artworks aesthetically and conceptually. In conclusion, the use of insect-derived paints depends on the artist's preferences and the messages they aim to convey through their works. In this compilation, the focus is on the Cochineal insect (Dactylopius coccus Costa, 1835 (Hemiptera: Dactylopiidae)), a creature native to South America that produces a potent natural red pigment known as "carmine". This pigment, utilized for obtaining the color red, has been an integral part of the art world for thousands of years. Indigenous cultures, in particular, have employed the dye extracted from this insect in the creation of textile dyes and paintings. Moreover, the Cochineal insect and its unique pigments have not only supported artistic expression but also captivated and inspired artists. During the Renaissance period, artists preferred the carmine pigment produced by the females of the Cochineal insect for obtaining bright and vivid red tones. This study delves into the history of the Cochineal insect, its role in art, and its perception in the modern world. Famous paintings created with dyes obtained from the Cochineal insect are discussed, exploring how pigments have found a place in the art world and how artists have utilized this extraordinary source to create distinctive works. [ABSTRACT FROM AUTHOR]

Ionic liquids attached to Bi7O9I3 fibers (located in the space between two fibers) can hold zinc oxide nanoparticles (NPs) well in this space and lead to the creation of a bifunctional nanocatalyst with high power (referred to as IL@Bi7O9I3-ZnO). The environmentally friendly and promising approach of photocatalytic degradation of organic dye residues serves as a means to address challenges that pose a threat to life forms. Here, an extremely effective Z-scheme heterojunction light-driven catalyst was deliberately formulated, constructed, and effectively employed for the eradication of erythrosine, methyl violet, and eriochrome black T. The outcomes acquired from the study revealed that the quantity of ZnO quantum dots directly impacts the degradation yield. The incorporation of quantum dots within the light-driven catalyst structure resulted in an enhancement in light-harvesting capability, charge transfer efficiency, and electron transfer rate. The evaluation of catalyst activity encompassed an examination of different elements in the catalyst used for producing and eliminating natural dyes. A prudent method has been suggested to optimize the collaboration between the Bi7O9I3 and ZnO groups at the nanoparticle locations on the catalyst, allowing for its recovery and subsequent reuse without any significant loss in reactivity for a minimum of ten successive cycles. [ABSTRACT FROM AUTHOR]

Context: The world's energy and environmental requirements are changing due to rapid population growth and industrial growth, and solar cells can be used to meet these demands. Dye-sensitized solar cells (DSSCs) are solar cells in which energy conversion occurs via a process similar to photosynthesis in plants. DSSC development is still in its infancy. DSSCs can operate under cloudy conditions and indirect sunlight and have attracted considerable attention due to their low cost and high efficiency. We designed two metal-free TPA-based dyes (Dye2 and Dye3) based on the reference dye Mg207 (Dye1) by increasing the donor strength of the molecule, as such dyes have shown enhanced efficiency in DSSCs. Moreover, the triphenylamine (TPA) moiety has been demonstrated to be a good donor that prevents charge recombination. Intramolecular charge transfer (ICT) from the donor to acceptor moiety was found in the sensitizers, and electrons were promoted to the conduction band (CB) of the TiO2 semiconductor. The negative binding energy of the dye@TiO2 clusters indicated that dye adsorption on the semiconductor surface was stable. The double donor increased the electron injection and electronic coupling constants in Dye2 and Dye3, indicating that these newly designed dyes have superior charge injection capacity. Accordingly, the efficiencies of DSSCs with Dye2 and Dye3 were 9.77% and 9.62%, respectively, and substitution with the TPA unit at the -R1 and -R2 positions in Dye1 resulted in better power conversion compared to the parent compound (9.09%). Increased donor strength improved photovoltaic performance by increasing current density and light-harvesting efficiency. This is a good molecular design approach for preparing targeted donor- π -acceptor (D- π -A) organic dyes with high DSSC efficiency. Methods: To predict the charge transport and optoelectronic characteristics of the TPA dyes, quantum chemical calculations were carried out using Gaussian16. The ground-state (S0) optimized geometries of the sensitizers were computed by utilizing DFT at the B3LYP/6-31G** level. The absorption spectra (λ max) were computed by employing TD-DFT with various functionals (B3LYP, PBE1PBE, CAM-B3LYP, and BHandHLYP) in the gas and solvent (DCM) phases. Among the studied functionals, BHandHLYP was found to be best at successfully reproducing the experimental data. Thus, the absorption spectra of the newly designed dyes and dye@TiO2 were calculated at the BHandHLYP/6-31G** level. The dye@TiO2 cluster optimizations were carried out at the B3LYP/6-31G**(LANL2DZ) level. [ABSTRACT FROM AUTHOR]

Using vacuum ultraviolet (VUV) to activate hydrogen peroxide (H2O2) to generate more reactive oxygen species (ROS) for decolonization and removal of dyes. The effects of H2O2 dosage, initial pH value of the solution, and initial dye concentration on the degradation of Acid Red G (ARG) and Rhoda- mine B (RhB) in the system were investigated. The results showed that when the dosage of H2O2 was 3 mmol/L, the decolorization rate of ARG and RhB at 80 mg/L could reach 96.3% and 98.4% respectively at 7 min. The removal rate of ARG and RhB increased with the increase of initial H2O2 concentration, but their promoting effect on the dye was limited when the concentration exceeded 3 mmol/L. The dye decolorization process follows a quasi first order kinetic model. Under acidic conditions, the decolorization and degradation of dyes have higher efficiency, while degradation is inhibited in alkaline environments. The free radical capture experiment and EPR detection results indicate that hydroxyl radicals (⋅ OH) and singlet oxygen (¹O2) are the main ROS, with ⋅ OH accounting for the main role.The presence of inorganic anions (HCO3, Cl-, NO3-, SO42-) can inhibit dye degradation. Through UV visible absorption spectroscopy analysis, it is preliminarily inferred that ARG is first attacked through the benzene ring, followed by the cleavage of azo bonds and naphthalene rings, and then mineralization;RhB mainly involves the destruction of conjugated structures, N-site deethylation, aromatic ring cracking, and mineralization. [ABSTRACT FROM AUTHOR]

The employment of green synthesized nanomaterials for water pollution prevention is increasing nowadays. Herein, Mn-doped ZnO nanoparticles were synthesized using Peganum Harmala seed extract and subsequently used for crystal violet (CV) dye removal from aqueous solutions. The first part of the study describes the preparation of the adsorbent (Mn-ZnO NPs) using a simple coprecipitation method. The surface properties of the material were characterized by Fourier transform infrared spectra (FTIR), scanning electron microscopy (SEM), and X-ray diffraction (XRD). The second part investigates the adsorption of CV dye onto the surface of the prepared Mn-ZnO NPs. Additionally, the isotherm, kinetics, and thermodynamics of the adsorption process were studied in detail. Batch adsorption analysis was carried out by evaluating different parameters, such as the amount of the adsorbent (0.01g to 0.04 g), CV concentration (20 to 80 mg/L), adsorption time (30 to 120 min), and temperature (35 to 65 ⁰C). The maximum CV dye adsorption capacity of the Mn-ZnO NPs was 45.60 mg/g. The thermodynamic study revealed the spontaneous, exothermic, and feasible nature of the adsorption process, primarily driven by physical forces. Kinetic and isotherm analyses indicated that the adsorption of the dye best fit the Freundlich isotherm and pseudo-second-order models, respectively. Mn-doped ZnO is considered an effective adsorbent for CV, benefiting from its rapid and easy preparation, non-toxic nature, and 94 % adsorption efficiency. The material holds potential for future applications in the removal of organic dyes from wastewater.. [ABSTRACT FROM AUTHOR]

Zinc oxide (ZnO) nanoparticles with diverse morphologies were synthesized using an economical and environmentally friendly co-precipitation method. The samples underwent characterization through X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy, and energy-dispersive spectra analysis. The photocatalytic degradation capabilities of the synthesized samples were assessed using organic dyes and antibiotics as model pollutants. SEM images revealed nanospheres, nanorods, and nanotubes structures of ZnO under three distinct conditions. The average crystallite sizes of hexagonal wurtzite ZnO samples were determined using Debye–Scherrer's formula from the full width at half maximum of XRD peaks, resulting in sizes of 52.80, 57.23, and 78.02 nm for ZnO nanospheres (ZnO-S), ZnO nanotubes (ZnO-T), and ZnO nanorods (ZnO-R), respectively. The optical band gap energies were measured at 3.25, 3.26, and 3.28 eV for ZnO-S, ZnO-T, and ZnO-R, respectively, demonstrating lower values compared to bulk ZnO (3.37 eV). Photocatalytic efficiency assessment using methylene blue indicated that ZnO-S exhibited the highest degradation efficiency (98.64%), followed by ZnO-T (97.63%) and ZnO-R (59.94%) under optimized conditions of 0.05 g/L catalyst dose, 90-min irradiation time, 130-W light intensity, and 1-mg/L methylene blue concentration. ZnO-S demonstrated effective photocatalysis in the ofloxacin degradation with a rate constant of 0.0112 min−1. According to a study on photocatalytic mechanisms, hydroxyl radicals play an important role in the degradation of pollutants. The photocatalyst maintains high photocatalytic efficiency even after five uses. Collectively, ZnO with different morphologies holds promise as a potential catalyst for environmental protection. [ABSTRACT FROM AUTHOR]

High‐efficiency and sustainable membrane purification technology is highly desirable but unattainable in the field of water treatment. 2D materials are emerging as very promising candidates for water treatment applications. However, membranes assembled by pure 2D materials lack reasonable structural and functional design, usually exhibiting relatively low water permeance, purification performance, and fouling resistance. Here, a mixed‐dimensional membrane is designed to solve the above‐mentioned problems by assembling two kinds of in situ grown 0D@2D functional building blocks of SiO2@GO and TiO2@MXene. Specifically, the obtained membrane exhibits high and maintainable water permeance of 2114 L m−2 h−1 bar−1 as well as high rejection rates toward organic dyes thanks to the plentiful firm water channels constructed by 0D@2D structures and the negative charges on both SiO2@GO and TiO2@MXene, respectively. Moreover, the 0D@2D TiO2@MXene serves as photocatalyst, rendering the composite membrane intriguing self‐cleaning function under UV irradiation, which is verified by the high recovery ratios of water permeance (97.5%) and dye interception rate (98.7%). Thus, this work offers a promising approach for the design of highly efficient and sustainable membrane for separation and purification purposes. [ABSTRACT FROM AUTHOR]

Photocatalysis, mainly using TiO2 as a catalyst, has emerged as a promising method to address the issue of wastewater treatment. This study explores the enhanced photocatalytic activity of TiO2 through the introduction of reduced graphene oxide (rGO) and cadmium sulfide (CdS) as selective metal dopants. The incorporation of rGO and CdS into the TiO2 lattice aims to optimize its photocatalytic properties, including bandgap engineering, charge carrier separation, and surface reactivity. The unique combination of CdS and rGO with TiO2 is expected to boost degradation efficiency and reduce the reliance on expensive and potentially harmful sensitizers. This experimental investigation involves the synthesis and characterization of TiO2-based photocatalysts. The photocatalytic degradation of methyl orange (MO) and methylene blue (MB) was assessed under controlled laboratory conditions, studying the influence of metal dopants on degradation kinetics and degradation efficiency. Furthermore, the synthesized photocatalyst is characterized by advanced techniques, including BET, SEM, TEM, XRD, and XPS analyses. The degraded samples were analyzed by UV-Vis spectroscopy. Insights into the photoexcitation and charge transfer processes shed light on the role of metal dopants in enhancing photocatalytic performance. The results demonstrate the potential of a TiO2-rGO-CdS-based photocatalyst in which 100% degradation was achieved within four hours for MO and six hours for MB, confirming efficient azo dye degradation. The findings contribute to understanding the fundamental principles underlying the photocatalytic process and provide valuable guidance for designing and optimizing advanced photocatalytic systems. Ultimately, this research contributes to the development of sustainable and effective technologies for removing azo dyes from various wastewaters, promoting environmental preservation and human well-being. [ABSTRACT FROM AUTHOR]

Dye-sensitized solar cells with synthesized phenothiazine derivative 3,7′-bis(2-cyano-1-acrylic acid)-10-ethyl-phenothiazine (PTZ) and commercial di-tetrabutylammonium cis-bis(isothiocyanato)bis(2,2′-bipyridyl-4,4′-dicarboxylato)ruthenium(II) (N719) dyes were fabricated and characterized based on current–voltage measurements. The effect of the utilization of individual dyes and its mixture, chenodeoxycholic acid as co-adsorbent addition, replacement of I−/I3− by Co2+/3+ ions in electrolyte and platinum by semiconducting polymer mixture poly(3,4-ethylenedioxythiophene) polystyrene sulfonate in counter electrode was studied. Additionally, the effect of polymer thickness on the photovoltaic performance of the device was evaluated. Prepared photoanodes were characterized by UV–Vis spectroscopy and atomic force microscopy. The further modification of DSSCs involving the fabrication of tandem solar cells was carried out. The higher power conversion efficiency 7.60% exhibited tandem photovoltaic cell sensitized with dyes mixture containing co-adsorbent, I−/I3− ions in the electrolyte, and platinum in the electrode. [ABSTRACT FROM AUTHOR]

Quantitative interference and its benefits on organic dye energy levels were examined in this study. The dye combined with the material had an absorption coefficient of 0.285 at 657 nm, according to UV–visible spectroscopy. From the results obtained, we observed a clear difference in the intensity of the absorption spectrum, which indicates that the energy levels of the dye have short absorption times. We also observed a decrease in the FWHM value, which indicates that the dye possesses a specific and sharp absorption effect. Rhodamine 6G was chosen as the optical material for its ability to be used to produce optical filters by controlling the inverse distribution between energy levels, allowing adjustments to be made immediately. The energy gap is greatly improved due to the use of Cu nanomaterials, as they cause a decrease in the free path and an increase in reflections, resulting in an increase in the absorption cross section. This optimization contributes to improved absorption efficiency and increased visual outcomes. Rhodamine 6G dye and copper nanoparticles were used in the experiment to study how quantum interference affects light absorption of an organic dye. The goal was to improve how well the dye absorbs light and get better optical results. The study came to the conclusion that quantum interference and improvements to nanostructures can be used to improve the energy levels and absorption efficiency of organic dyes. This will help to develop more advanced photonic applications in the future and make optical technology more useful. [ABSTRACT FROM AUTHOR]

Mesoporous titania films with worm-like patterns were fabricated on indium-tin oxide (ITO) glass by dip-coating skill, and were characterized systematically. Impacts of the process and technical parameters on the formation of the films were investigated. The mesoporous films were characterized by low-angle X-ray diffraction (XRD) and wide-angle XRD, transmission electron microscopy (TEM), scanning electron microscope (SEM), linear sweep voltammograms and nitrogen adsorption/desorption isotherms. Subsequently, the films were used in a photoelectrocatalytic system for the degradation of methyl orange. The influence of operation variables, including pH values, bias potential, light intensity, organics concentration and the mass of the films, on the degradation of the dye was investigated in details. More than 96 % degradation of the organics was achieved in 2 h. The kinetic results for the photoelectrocatalytic oxidation of the organic were also presented in this paper. [ABSTRACT FROM AUTHOR]

Pulsed underwater direct current discharge is considered as a tool for a one-step process for ferrite synthesis and organic dye removal. The formation of cobalt, nickel and titanium ferrites during the discharge firing process was confirmed by methods of dynamic light scattering and X-ray phase analysis. The transformation of dye molecules (fluorescein, methylene green) during the combined action of plasma and ferrites was detected by UV absorption spectroscopy. The contributions of the separate action of plasma and ferrites to the process of dye removal from the solution were investigated. It was found that the synthesized structures have a high sorption capacity. It was found that fluorescein can be used as an indicator for the presence of nickel ferrites. [ABSTRACT FROM AUTHOR]

In this paper, undoped and copper-doped ZnO nanoparticles (NPs) were successfully synthesized using a gliding arc discharge (GAD) plasma technique, which is a sustainable, cost-effective, and scalable method. This method offers several advantages over traditional synthesis methods. The synthesized NPs were characterized by various techniques to understand their physicochemical properties. XRD analysis confirmed the presence of characteristic peaks of pure ZnO, while doped samples exhibited additional peaks corresponding to CuO crystal planes, indicating the successful incorporation of Cu into the lattice. As obvious, bare ZnO showed absorption peak at 378 nm corresponding to the band gap of 3.21 eV. The band gap of Cu-doped samples increased systematically, i.e., 3.35 eV for 2% Cu, 3.47 eV for 4% Cu, and 3.66 eV for 6% Cu. SEM images revealed aggregation and increase in particle size with the increasing in Cu concentration. EDAX analysis revealed a decrease in the weight percentage of oxygen and zinc with the increase in Cu concentration, suggesting structural changes within the lattice. Furthermore, the antibacterial activity against Gram-positive and Gram-negative bacteria, antioxidant activity, and photocatalytic activity against three different organic dyes such as Brilliant Cresyl Blue (BCB), Methylene Blue (MB), and Congo Red (CR) was studied. It is found that the photocatalytic activity of ZnO NPs varies with Cu concentration, leading to a decrease in its performance. The antibacterial activity of the NPs was also assessed, with undoped ZnO NPs showing dose-dependent effects against bacteria, while the Cu-doped ZnO NPs exhibited decreased efficacy. Interestingly, Cu doping significantly enhanced the antioxidant activity of the NPs compared to the undoped ZnO. [ABSTRACT FROM AUTHOR]

The increasing global demand for energy and growing environmental concerns emphasize the crucial role of solar energy as a sustainable and nondepletable resource. Solar cells, particularly dye‐sensitized solar cells (DSSCs), have gained prominence due to their efficient conversion of solar power, ecofriendly manufacturing processes, and noteworthy stability. Current research in sustainable energy focuses on transitioning from metal‐based to metal‐free organic materials. Tandem solar cells, combining n‐type and p‐type semiconductors sensitized with diverse photoactive dyes, show potential to surpass thermodynamic limits in photon conversion efficiency. Notably, the exploration of n‐type DSSCs as photoanodes in tandem architectures is promising. However, the absence of efficient p‐type photoactive cathodes remains a significant obstacle. Global research efforts are dedicated to addressing charge recombination issues in NiO‐based devices to enhance the efficiency of p‐type DSSCs. The success of any DSSC hinges on the selection of dyes/sensitizers with suitable anchoring groups, wide absorption in the visible–NIR region, and a high extinction coefficient. This article comprehensively reviews advancements in developing highly efficient p‐type sensitizers, emphasizing their pivotal role in unlocking the full potential of tandem solar cells. [ABSTRACT FROM AUTHOR]

One of the most important concerns in developing efficient heterojunction photocatalysts for the photodegradation of environmental contaminants is the enhancement and acceleration of photocarrier separation. In this study, novel nanocomposite photocatalysts of Ag–AgVO3 nanorods grafted with Zn0.5Mn0.5Fe2O4 metal ferrites nanoparticles were developed by using facial hydrothermal and coprecipitation techniques for the effective photodegradation of Rhodamine B (Rh B) under visible light exposure. The fabricated materials were analyzed in detail using scanning electron microscopy, energy-dispersive X-ray spectroscopy (EDS), nitrogen adsorption/desorption, transmission electron microscopy (TEM), photoluminescence spectroscopy (PL), vibrating sample magnetometer, and ultraviolet–visible diffuse reflectance spectroscopy (DRS). The results showed an efficient contribution when compared to the earlier research. The TEM showed a hybrid of nanorods of supported composite with metal ferrite and Ag attached on the surface, consistent with field emission scanning electron microscopy and EDS results. The DRS expressed a lower band gap for supported nanocomposites (1.5 eV), which, arranged with PL, showed a lower recombination rate of supported nanocomposites. The surface properties showed that the supported hybrid might be as small as 45.42 nm or as large as 20.33 nm compared with others. When comparing the photocatalytic activity of pure AgVO3, Ag/AgVO3, and Zn0.5Mn0.5Fe2O4 photocatalysts, the performance of Ag–AgVO3/Zn0.5Mn0.5Fe2O4 nanocomposite photocatalyst was clearly superior (more than 99.9% degradation efficiency was achieved). The boosted activity the Ag–AgVO3/Zn0.5Mn0.5Fe2O4 photocatalyst system was justified by Z-system heterojunction induced by the plasmonic effect, and the suggested mechanism was investigated by quenching of reactive species by scavengers. The degradation performance was achieved under optimum conditions (pH = 2, 20 ppm of pollutant concentration, 120 mM of hydrogen peroxide, 1 g/L of catalysts dose). The results showed that after 240 min of visible irradiation resulted in the high (chemical oxygen demand) and (total organic carbon) reductions with a removal efficiency of (85) to (90%) for Rh B dye. The fabricated Ag–AgVO3/Zn0.5Mn0.5Fe2O4 nanocomposites were effective in the degradation of organic pollutants in wastewater treatment.

Two-dimensional (2D) materials have recently drawn interest in various applications due to their superior electronic properties, high specific surface area, and surface activity. However, studies on the catalytic properties of the 2D counterpart of V2O5 are scarce. In the present study, the catalytic properties of 2D V2O5 vis-à-vis bulk V2O5 for the degradation of methylene blue dye are discussed for the first time. The 2D V2O5 catalyst was synthesized using a modified chemical exfoliation technique. A massive increase in the electrochemically active surface area of 2D V2O5 by one order of magnitude greater than that of bulk V2O5 was observed in this study. Simultaneously, ~ 7 times increase in the optical absorption coefficient of 2D V2O5 significantly increases the number of photogenerated electrons involved in the catalytic performance. In addition, the surface activity of the 2D V2O5 catalyst is enhanced by generating surface oxygen vacancy defects. In the current study, we have achieved ~ 99% degradation of 16 ppm dye using the 2D V2O5 nanosheet catalysts under UV light exposure with a remarkable degradation rate constant of 2.31 min−1, which is an increase of the order of 102 from previous studies using V2O5 nanostructures and nanocomposites as catalysts. Since the enhanced photocatalytic activity emerged from the surface and optical properties of the catalyst, the current study shows great promise for the future application of 2D V2O5 in photo- and electrocatalysis. [ABSTRACT FROM AUTHOR]

Four families of structurally related chiral π‐conjugated oligomers bearing a hydroquinone (HQ), 1,5‐dihydroxynaphthalene (Naph), benzo[1,2‐b:4,5‐b']dithiophene‐4,8‐diol (BDT) or 9H‐carbazole (CBZ) central core, for a total of 11 new compounds, have been synthesized by simple and versatile synthetic strategies involving Pd‐catalyzed cross‐coupling protocols: a Suzuki‐Miyaura reaction, a Sonogashira/desilylation/Sonogashira sequence or a Sonogashira/desilylation/acyl Sonogashira sequence. A systematic investigation of the optical and chiroptical features of the final chiral dyes was performed in chloroform solution and on spin‐coated thin films. The ECD investigation was crucial in revealing that, even within the same family of organic dyes, minor variations in the nature and length of the π‐conjugated backbone can result in very different solid‐state arrangements at different hierarchical scales. [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]

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]

Developing aggregation‐induced emission luminogens (AIEgens) is a unique strategy for alleviating concentration quenching of π‐conjugated organic compounds. This AIE behaviour can be induced not only in organic dyes with rotors but also in invertible π‐conjugated systems. Herein, intramolecular Ullmann coupling was used to synthesize π‐twisted triskelion‐shaped AIEgens (2F, 2G, and 2H), in which benzo[f], [g], and [h] coumarins were fused into the benzene core to form a helical propeller shape. These structural isomers had unique molecular thicknesses and planarities depending on the fusion mode of the benzocoumarin. The racemic crystals, PPP and MMM, had different overlapping molecular configurations because of their twisted molecular frameworks. Compounds 2F, 2G and 2H demonstrated weak fluorescence emission in diluted solutions resulting from molecular motions caused by the isomerization process during molecular inversion. By comparison, aggregates exhibited enhanced emission intensity. These π‐twisted triskelions exhibited the characteristics of AIEgens. [ABSTRACT FROM AUTHOR]

Developing a low-cost and highly efficient semiconductor photocatalyst for the decomposition of organic pollutants and antibiotics is highly desirable. Herein, FeOOH nanosheets were prepared using a liquid-phase stirring technique and combined with ZnCdS (ZCS) nanoparticles to construct FeOOH/ZCS nanocomposite photocatalysts. The photocatalytic efficiency of the FeOOH/ZCS nanocomposite was evaluated for the decomposition of various pollutants, including rhodamine B, methylene Blue, and tetracycline. The FeOOH/ZCS nanocomposite exhibited significantly higher photocatalytic performance for the decomposition of various organics. Moreover, the optimized FeOOH/ZCS retained more than 90% of its initial photocatalytic activity even after five successful runs. Radical quenching test and electron spin resonance (ESR) analysis revealed that hydroxyl radicals (•OH) play a dominant role for the decomposition of organics. The FeOOH/ZCS Z-scheme heterojunction significantly facilitates higher charge transfer efficiency and the generation of reactive radicals, resulting in excellent photocatalytic degradation performance. This work offers a new approach to synthesis FeOOH-based photocatalyst for the elimination of organics and antibiotics in water. [ABSTRACT FROM AUTHOR]

In the current research, we prepared a polymeric framework, {[Cu(C2O4)(C10H8N2)]·H2O·0.67(CH3OH)]}n (1) (where C2O4 = oxalic acid; C10H8N2 = 2,2-bipyridine), and explored this compound for adsorption of methylene blue (MB) and methyl orange (MO). The crystal structure of the compound consists of a Cu(ox)(bpy) unit connected via oxalate to form a 1D polymeric chain. This polymeric chain has adsorption capacities of 194.0 and 167.3 mg/g for MB and MO, respectively. The removal rate is estimated to be 77.6% and 66.9% for MB and MO, respectively. The plausible mechanisms for adsorption are electrostatic, π-π interaction, and OH-π interaction for dye stickiness. The adsorbent surface exhibits a negative charge that produces the electrostatic interaction, resulting in excellent adsorption efficiency at pH 7 and 8. The pseudo-first-order kinetic model is selected for the adsorption of MB and MO on the adsorbent. The reported compound has remarkable efficiency for sorption of organic dyes and can be useful in wastewater treatment. [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]

AbstractIn this report we present a simple synthesis of a nickel-based metal organic framework (MOF-Ni) at the room temperature using a solution of dimethylformamide (DMF), ethanol and distilled water. The MOF-Ni synthesized in various solvents displayed numerous different properties and advantages over other materials including easy synthesis procedure, good crystallinity, rigidity, and robust chemical stability. X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), and thermal gravimetric analysis (TGA) were employed to analyze the as-synthesized MOF-Ni. The as-obtained MOF-Ni was used to investigate its adsorption kinetics of red telon dye (RTL) molecules. The effects of time (30–270 min), initial RTL concentration (20–300 mg/L), adsorbent dose (2–50 mg), solution pH (2–12), and temperature (10–80 °C) were investigated. The pseudo-first order rate equation was able to provide the best description of the adsorption kinetics data in the studied time scale. The Langmuir and Freundlich adsorption models were applied to describe the equilibrium isotherms, and the isotherm constants were also determined. Dye adsorption turned out to strongly depend on pH, and a low pH was found to increase the amount of adsorbed dyestuff. Compared with other samples, MOF-Ni synthesized in (DMF ​+ ​C2H5OH ​+ ​H2O) had a significantly enhanced adsorption ability for RTL dye. The MOF-Ni high adsorption capacity for RTL dye was attributed to the electrostatic attraction/repulsion phenomena. Moreover, MOF-Ni showed an improved stability at 370, 417, and 423 °C temperatures. The results obtained through our experiments suggested that our porous MOF-Ni microstructures synthesized in DMF ​+ ​C2H5OH ​+ ​H2O have potential applications for treating wastewaters containing RTL dyes. [ABSTRACT FROM AUTHOR]