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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]

Due to the advancement of industrialization, water pollution has become an alarming global issue. Many organic dyes, such as crystal violet and rhodamine B, present in industrial wastewater are causing severe health problems. Both of these dyes are carcinogenic. For their degradation, ferrites are synthesized in this research. Ferrites have high absorbing potential in visible regions and fast movement of charge carrier species. Therefore, the ferrites are potentially used in photocatalysis to purify contaminated water. Graphitic carbon nitride shows enhanced separation of charges, which lowers the rate of recombination of charge carrier species. Lithium nickel ferrite, lithium nickel ferrite doped with terbium, and its composite with graphitic carbon nitride (g-C 3 N 4) are synthesized by sol-gel and ultra-sonication methods, respectively. The prepared samples are analyzed by X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, Scanning electron microscopy (SEM), Electrochemical impedance spectroscopy (EIS), and Mott-Schottky analysis. The bandgap of LiNiFe 2 O 4 and LiNiTbFe 2 O 4 was 2.35 eV, and 1.87 eV, respectively. LiNiTbFe 2 O 4 @g-C 3 N 4 degraded 86 % crystal violet and 83 % rhodamine B in 120 min. The LiNiTbFe 2 O 4 @g-C 3 N 4 composite showed the maximum degradation and can be potentially used in wastewater treatment. [ABSTRACT FROM AUTHOR]

The rampant misuse of organic dyes has exacerbated environmental pollution to an alarming degree. SrBi 4 Ti 4 O 15 , a layered perovskite semiconductor material, demonstrates considerable potential in the degradation of organic dyes, and efforts have been made to enhance its photocatalytic efficiency. In this study, La3+ doping was utilized to synthesize SrBi 4-x La x Ti 4 O 15 (x = 0, 0.10, 0.15, 0.25, 0.40) nanosheet photocatalysts, and their photocatalytic performance and underlying mechanisms were comprehensively investigated. XRD and Raman spectroscopy revealed that La3+ doping replaced Bi3+ at the A-site, resulting in a reduction of the interlayer spacing of [TiO 6 ] octahedra. Combined with DFT calculations, La3+ doping was found to widen the band gap of SrBi 4 Ti 4 O 15 and raise the Fermi level. Additionally, La3+ doping significantly increased the ratio of the Ti 3d component at the bottom of the conduction band, favoring the migration of photogenerated electrons along the [TiO 6 ] octahedra and accelerating the separation of photogenerated carriers. SEM and BET analyses revealed that La3+ doping not only increased the size of the nanosheets but also significantly enhanced their specific surface area, thereby exposing more active sites. Degradation experiments of Rhodamine B (Rh B) under UV light demonstrated that the photocatalytic efficiency of SrBi 3.75 La 0.25 Ti 4 O 15 (k = 0.0514 min-1) was 2.66 times higher than that of the original SrBi 4 Ti 4 O 15 (k = 0.0193 min-1). The theoretical degradation pathway of Rh B was elucidated using LC-MS analysis and the developmental toxicity of potential intermediates was analyzed. Moreover, the SrBi 3.75 La 0.25 Ti 4 O 15 photocatalyst also exhibited excellent degradation efficacy against Methylene Blue (MB), Crystal Violet (CV), and Methyl Orange (MO). This study provides both theoretical and experimental insights into improving the photocatalytic performance of SrBi 4 Ti 4 O 15 , thereby enhancing its potential for industrial application. [Display omitted] [ABSTRACT FROM AUTHOR]

A facile wet chemical approach was adopted to synthesize zinc oxide, titanium dioxide, and iron (II, III) oxide, followed by the synthesis of ZnO–TiO2–Fe3O4 nanocomposite via physical mixing. The synthesized nanoparticles were characterized using X‐ray diffraction, UV–visible spectroscopy, vibrating sample magnetometry, transmission electron microscopy, and energy‐dispersive X‐ray spectroscopy to investigate various physical and chemical characteristics of the prepared samples. Furthermore, the catalytic reduction of methylene blue (MB) and rhodamine B (Rh B) dyes was carried out using prepared nanomaterials as catalysts under UV–visible light illumination. It was observed that the degradation efficiency of the nanocomposite was equivalent to or slightly better than TiO2 nanoparticles and higher than ZnO nanoparticles against both dye solutions. Its removal efficiency using an external magnetic field is much higher than that of the constituent nanoparticles, owing to its higher saturation magnetization. So, the obtained results suggest that the produced nanocomposite can be employed as a high‐potential catalyst for reducing organic dyes and pollutants in wastewater treatments. [ABSTRACT FROM AUTHOR]

Two novel metal‐free organic dyes, namely the mono‐anchoring KMT1 and di‐anchoring KMT2 dyes, have been synthesized to function as photosensitizers for utilizing in photocatalytic hydrogen production systems. They adopt the donor‐donor‐π‐acceptor and donor‐donor‐(−π‐acceptor)2 configurations, respectively, featuring triphenylamine and fluorene moieties as electron donors, thiophene as the π‐bridges and cyanoacrylic acid as the acceptors/anchoring groups. It was found that the photocatalytic performance of the di‐anchoring dye significantly outperforms that of its mono‐anchoring counterpart. KMT2‐based photocatalytic system demonstrated remarkable performance, producing 3520 μmol (84.9 mL) of hydrogen over a span of 257 hours under blue light irradiation, with a turnover number (TON) of 56300, a turnover frequency (TOFi) of 1862.7 h−1, an initial hydrogen production activity (activityi) of 1164180 and an apparent quantum yield (AQYi %) of 19.9. This performance is among the top‐tier when compared to other dyes used in similar photocatalytic systems. The results clearly illustrate that the di‐anchoring dye possesses several advantages, including a broad absorption spectrum, higher absorptivity, and a relatively slower charge recombination rate. These attributes collectively contribute to its superior overall performance in photocatalysis. [ABSTRACT FROM AUTHOR]

Blast furnace slag (BFS) is a kind of waste produced in industrial production, as well as a valuable secondary resource. In this paper, layered double hydroxides composites (BFS/LDHs) were prepared by aqueous polymerization, with industrial waste BFS as modifier and magnesium nitrate, aluminium nitrate, and urea as raw materials. BFS/LDHs have been characterized by using scanning electron microscopy (SEM), fourier infrared spectrometer (FT IR), x-ray diffraction (XRD), and the specific surface area analyser (BET). The adsorption of BFS/LDHs on Cu (II) and methylene blue (MB) was investigated by batch experiments. The results showed that the adsorption capacity of BFS/LDHs to Cu (II) is stronger than that of MB. What's more, the solid concentration effect was found in the process of sorption kinetics and sorption isotherms. The sorption kinetics curves of Cu (II) and MB on BFS/LDHs were well fitted by the quasi-second-order kinetics under different adsorbent concentrations. Langmuir and Freundlich sorption isotherm models were used to analyse the adsorption. It showed that the adsorption conforms to Langmuir and Freundlich's adsorption isotherm models. The BFS/LDHs composites have good recycling availability in this adsorption process of Cu (II) and MB, the removal capacity of which was reduced by 16.1% and 3.8% after being recycled for six times, respectively. More importantly, BFS/LDHs composites are not only expected to become a sewage treatment agent, but also to solve the problem of industrial waste treatment, which is a win–win strategy. [ABSTRACT FROM AUTHOR]

In recent years, the extensive use of organic dyes has caused great pollution to the water environment. Zinc silicate with excellent adsorption and photocatalytic properties has been widely used in the treatment of organic dye wastewater. Therefore, we successfully prepared zinc silicate nanomaterials by simple hydrothermal method using zinc sulfate heptahydrate (ZnSO4·7H2O) and tetraethyl orthosilicate (TEOS) as raw materials, and cetyltrimethylammonium bromide (CTAB) as surfactant, and applied them to the treatment of organic dye wastewater. The composition, morphology and specific surface area of zinc silicate nanomaterials were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), field emission scanning electron microscopy (FESEM), and Brunauer–Emmett–Teller (BET) method. The results show that the phase composition of the products has a transformation from hemimorphite Zn4Si2O7(OH)2·H2O to vermiculite Zn2SiO4, and the morphology has also an obvious change from nanosheets, nanoflowers to nanoparticles with the increase of TEOS content. The specific surface area and pore volume are 199.8 m2/g and 0.441 cm3/g for the flower-like zinc silicate nanomaterials. The zinc silicate nanomaterials show excellent adsorption and photocatalytic properties for organic dyes from aqueous solutions, and the maximum removal efficiencies can reach 89.8% and 96.2% for rhodamine B (RhB) and methylene blue (MB), respectively. [ABSTRACT FROM AUTHOR]

Organisms with active camouflage ability exhibit changeable appearance with the switching of environments. However, manmade active camouflage systems heavily rely on integrating electronic devices, which encounters problems including a complex structure, poor usability, and high cost. In the current work, we report active camouflage as an intrinsic function of materials by proposing self-adaptive photochromism (SAP). The SAP materials were fabricated using donor-acceptor Stenhouse adducts (DASAs) as the negative photochromic phases and organic dyes as the fixed phases (nonphotochromic). Incident light with a specific wavelength induces linear-to-cyclic isomerization of DASAs, which generates an absorption gap at the wavelength and accordingly switches the color. The SAP materials are in the primary black state under dark and spontaneously switch to another color upon triggering by transmitted and reflected light in the background. SAP films and coatings were fabricated by incorporating polycaprolactone and are applicable to a wide variety of surfaces. [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]

We introduce the community to the remarkable fact that two significant discoveries in the field of organic photoswitches are associated to the Rubizhne (Rubezhnoe) branch of the Research Institute of Organic Intermediates and Dyes during the last century. The institute in Rubizhne was a place where researchers of various nationalities carried out studies of organic dyes for printing and textiles. These efforts resulted in the discoveries of photoswitchable hemithioindigos by M. A. Mostoslavskii and peri‐aryloxyquinones by Yu. E. Gerasimenko. Herein, based on the available literature, we reconstruct the circumstances surrounding these outstanding findings and highlight the unique role of the Rubizhne institute as a research center. Furthermore, we demonstrate the impact of the results of the Rubizhne researchers on the field of photoswitchable molecules. [ABSTRACT FROM AUTHOR]

This scientific paper presents a novel approach to explore and predict the potential of imidazole-based organic dyes for use in Dye-Sensitized Solar Cells (DSSCs) using a machine learning web application. The design of efficient and cost-effective organic dyes is critical to enhance the performance of DSSCs. Traditional experimental methods are time-consuming and resource-intensive, making it challenging to screen a large number of potential dyes. In this study, we propose a machine learning-based approach to accelerate the discovery process by predicting the photovoltaic performance of imidazole-based organic dyes. Machin learning predictions provide valuable insights into the expected PCE% and behaviors of the molecules toward DSSCs. Based on the RDKit library, several fingerprints such as Molecular ACCess System, Avalon, Daylight, Pharmacophore and Morgan with different radius (r2, r3, r4), were studied. In addition, more than 20 ML algorithms using different cross validation (3, 5, 7, 10) were also evaluated. Among of these, Deep Neural Network models of MLPRegressor algorithm based on the daylight fingerprint shows a significant coefficient of determination combined with the lowest errors. Utilize the trained ML models to screen of 50 million SMILE structure for identify promising imidazole and nitrogen-containing derivative as a doner group. By replacing the donor groups in the well-known MK2 dye structure with the top imidazole derivatives proposed by machine learning, significant improvements in PCE were observed, increasing from 7.70% to as high as 11.49%, representing nearly a 50% enhancement over the control. DFT calculations confirm the ML predictions and clarify the significantly higher oscillator strength and charge transfer properties of MK2-DM1, compared to MK2. This result provides a promising pathway for developing new dye materials that can push the efficiency limits of DSSCs, leading to more efficient solar energy conversion technologies in the future. In addition, a developed web application offers a user-friendly interface for researchers to input their molecular structures and obtain PCE% predictions toward DSSCs. This information can guide researchers in designing a new imidazole dye with high photovoltaic performance to validate and refine the predictions without time consuming. [ABSTRACT FROM AUTHOR]

The search for materials to treat wastewater is especially crucial. Herein, we have prepared 1D molybdenum oxide (MoO 3) nanobelts through a hydrothermal approach. The binary (MoO 3 /SiO 2) and ternary composites of MoO 3 /SiO 2 /MXene were synthesized via ultrasonication route. The as-prepared MoO 3 , MoO 3 /SiO 2, and MoO 3 /SiO 2 /MXene composites were employed to investigate the photocatalytic behavior of two organic dyes, methyl orange (MO) and crystal violet (CV). The % degradation of MO in the presence of MoO 3 nanobelts and MoO 3 /SiO 2 was calculated to be 48.9 % and 74.4 %, respectively. In the case of CV dye, the degradation (%) was observed at 53.7 % and 75.9 %. The MoO 3 /SiO 2 /MXene composite revealed the best photocatalytic behavior against both MO and CV dyes by removing 94.7 % and 97.7 % under visible light irradiation. The rate constant values of MoO 3 nanobelts, MoO 3 /SiO 2 and MoO 3 /SiO 2 /MXene composite for MO dye were calculated to be 0.00568 min−1, 0.01156 min−1, and 0.02399 min−1 and for CV dye 0.00679 min−1, 0.01208 min−1, and 0.02798 min−1 respectively. A scavenging test was carried out to monitor the main photo-active species that take part during the photocatalysis and hydroxyl radicals were found to be the highly active species during whole photodegradation progression. The SiO 2 particles function as a good adsorbent medium and transfer the adsorbed organics toward more active sites to advance the reaction. 2D MXene nanosheets, as good conductors, reduce the recombination rate of charges, offer large surface area, and facilitate fast transfer of charges. The results suggest that MoO 3 /SiO 2 /MXene composite is a potential contender for wastewater remediation applications. [Display omitted] • Ternary composite (MoO 3 /SiO 2 /MXene) was synthesized using an ultrasonication approach, with a crystallite size of 19.48 nm. • SEM analysis confirmed the successful synthesis of MoO 3 nanobelts and their ternary composite with SiO 2 and MXene sheets. • The synthesized samples were utilized for the photodegradation of two organic dyes, Crystal Violet and Methyl Orange. • The MoO 3 /SiO 2 /MXene nanocomposite demonstrated the highest photocatalytic activity against both dyes. [ABSTRACT FROM AUTHOR]

A pH responsive monometallic‐clay nanocomposite hydrogel, sodium alginate‐cl‐poly (N‐hydroxy ethyl acrylamide‐co‐methacrylic acid) @ Au/ montmorillonite clay (SANCHG@Au/MMT) is synthesized in situ using sodium alginate (SA) as a polysaccharide. Two other nano composite hydrogels namely sodium alginate‐cl‐poly (N‐hydroxy ethyl acrylamide‐co‐methacrylic acid) @ Au (SANCHG@Au) and sodium alginate‐cl‐poly (N‐hydroxy ethyl acrylamide‐co‐methacrylic acid) @ montmorillonite clay (SANCHG@MMT) are also prepared. All the synthesized nano composite hydrogels are characterized using various techniques. Water swelling of the three hydrogels along with their textile dye adsorption properties is evaluated in congo red (CR), benzopurpurin (BP) and tartrazine (TZ) from their aqueous solutions. Among the three hydrogels the % water swelling of SANCHG@Au/MMT is superior (396% at pH = 8) and also the adsorption capacity over the other two. The dye adsorption property of SANCHG@Au/MMT is found to be pH sensitive. Adsorption follows both the Langmuir adsorption isotherm with Qmax values 512.19 mg.g−1 for CR at pH = 4, 476.09 mg.g−1 at pH = 4 for BP and 454.79 mg.g−1 at pH = 6 for TZ respectively and Dubinin–Radushkevich isotherm model. The kinetic data fit with pseudo second order kinetic model. Thermodynamic parameters like negative ∆G0 and positive ∆H0 values suggest that the adsorption process is spontaneous and endothermic in nature. [ABSTRACT FROM AUTHOR]

Herein, we report the synthesis of new near‐infrared (NIR) fluorescent dyes based on the pyridinium−cyclic enolate betaine (PCB) skeleton. The formation of the electron‐donor−π−electron‐acceptor (D−π−A) type dye with the electron‐donating N,N‐diphenyl amino group and the electron‐accepting PCB skeleton through a series of π−spacers allowed us to achieve NIR fluorescence. Particularly, a dye with a thienylisothianaphthene spacer showed NIR fluorescence with a significant intensity (λPL=822 nm, ΦPL=0.19 in DMSO). Detailed experimental and theoretical analyses suggested that the structural relaxation to a planar quinoidal form in the S1 state would be critical for intense NIR fluorescence. [ABSTRACT FROM AUTHOR]

In recent years, significant advances in enhancing the quantum yield (QY) of trivalent lanthanide (Ln3+) ion-based nanoparticles have been achieved through photosensitization, using host matrices or capping organic ligands as photosensitizers to absorb incoming photons and transfer energy to the Ln3+ ions. The Ln3+ ion-based nanoparticles possess several excellent fluorescent properties, such as nearly constant transition energies, atomic-like sharp transitions, long emission lifetimes, large Stokes shifts, high photostability, and resistance to photobleaching; these properties make them more promising candidates as next-generation fluorescence probes in the visible region, compared with other traditional materials such as organic dyes and quantum dots. However, their QYs are generally low and thus need to be improved to facilitate and extend their applications. Considerable efforts have been made to improve the QYs of Ln3+ ion-based nanoparticles through photosensitization. These efforts include the doping of Ln3+ ions into host matrices or capping the nanoparticles with organic ligands. Among the Ln3+ ion-based nanoparticles investigated in previous studies, this review focuses on those containing Eu3+, Tb3+, and Dy3+ ions with red, green, and yellow emission colors, respectively. The emission intensities of Eu3+ and Tb3+ ions are stronger than those of other Ln3+ ions; therefore, the majority of the reported studies focused on Eu3+ and Tb3+ ion-based nanoparticles. This review discusses the principles of photosensitization, several examples of photosensitized Ln3+ ion-based nanoparticles, and in vitro and in vivo biomedical fluorescent imaging (FI) applications. This information provides valuable insight into the development of Ln3+ ion-based nanoparticles with high QYs through photosensitization, with future potential applications in biomedical FI. [ABSTRACT FROM AUTHOR]

Photocatalytic degradation is a leading technology for complete mineralization of organic dyes in the ocean. In this work, a new viologen-bearing silver-thiocyanate-based photocatalyst, i.e., {(i-PrV)[Ag2(SCN)4]}n (i-PrV2+ = isopropyl viologen) has been synthesized and structurally determined, with results showing that it can exhibit excellent degradation performance on rhodamine B (RhB) in artificial seawater. The planar i-PrV2+ dications are confined in the free voids of the [Ag2(SCN)4]n2n− layer with a two-dimensional (6,3) mesh, and strong C-H···S hydrogen bonds contribute to its structural stabilization. This photocatalyst was further characterized by powder X-ray diffraction (PXRD), UV-Vis, fluorescence, and photo/electrical responsive measurements, pointing to its application in visible-light-driven catalysis. Interestingly, using this photocatalyst, good photocatalytic degradation performance on rhodamine B in artificial seawater could be observed. The dye pollutant could be degraded with a high degradation ratio of 87.82% in 220 min. This work provides a promising catalyst for organic dye-type ocean pollutant treatments. [ABSTRACT FROM AUTHOR]

Manganese oxide loaded on activated alumina beads (MnOx/AABs) was prepared by one-pot hydrothermal method and applied to activate periodate (PI) towards the degradation of Rhodamine B (RhB) and other organic dyes. The catalyst was first characterized by scanning electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy (XPS) and N2 sorption. Subsequently, the effects of catalyst dosage, oxidant dosage, initial pH as well as co-existing inorganic anion and humic acid on the performance of the MnOx/AABs/PI system were studied. Under optimum conditions (catalyst dosage = 15 beads, PI dosage = 0.2 g/L), the removal efficiency of 50 mg/L RhB reached 99.4%, with a total organic carbon removal efficiency of 51.0%. The removal efficiencies of several other organic dyes were in the range of 70%-95.1%. The leached amount of Mn was measured to be 0.027 mg/L. Mechanism studies revealed that 1O2, IO3⋅ and O2⋅− were identified to be responsible in this reaction system, and 1O2 played a decisive role. In addition, IO4− was converted to IO3− without other toxic products during the degradation process. Reusability test in both the batch and continuous modes showed that the catalyst could be efficiency regenerated by calcination. Combining the results of liquid chromatography-mass spectrometry (LC–MS) and density functional theory calculations, the possible degradation pathway of RhB was proposed. Finally, toxicity evaluation of the degradation products of RhB was performed by theoretical calculations as well as experimental tests with Vigna radiata. [ABSTRACT FROM AUTHOR]

A sensitive surface enhanced Raman spectroscopy (SERS) substrate based on SiO2@Ag core-shell with a QuEChERs pretreatment method were constructed for the determination of carbendazim residue in tobacco leaves. The SERS substrate was formed by self-assembly of monolayer homogeneous SiO2 nanospheres onto silicon wafer following by vacuum thermal evaporation of silver film. The QuEChERs pretreatment method was used to eliminate the interfering effects of pigments and organic acids in tobacco leaves. The results for carbendazim in tobacco leaves show the limit of detection (LOD) of the SERS substrate was 0.1 mg/kg and the recovery rate was from 82.56% to 95.93%. The proposed low-cost sensitive SERS substrates provide potential application for tobacco safety monitoring. [ABSTRACT FROM AUTHOR]

The removal of persistent dye pollutants from wastewater streams has drawn a lot of interest by the scientific community and photocatalysis is the most widely accepted practical strategy for addressing environmental contamination. Transition metal oxides are proved to be the most prospective catalysts for efficient and environment-friendly wastewater treatment because of their significant photocatalytic activity, excellent solubility and durability. Here, we describe a simple, eco-sustainable and cost-effective strategy for the synthesis of ZnO nanoparticles using Morinda umbellata leaf extract. The phytochemicals such as polyphenols, flavonoids and tannins present in the leaf extract act as reducing and stabilising agents. We investigated the photocatalytic activity of synthesised ZnO nanoparticles to break down organic dyes like Congo red (CR) and Malachite green (MG) in aqueous media. In aqueous solution, at ambient temperature, ZnO nanoparticles showed outstanding photocatalytic degradation efficiency of 98.9% (20 ppm) for the MG dye and 92.8% (10 ppm) for the CR dye at pH values of 10 and 6 respectively, in a short period of time. The optimum catalyst dosage was observed to be 0.1 and 0.125 g for MG and CR respectively. From the scavenger studies using different scavengers, it is confirmed that the superoxide radical is the main reactive species involved in the photocatalytic degradation of MG and CR. The kinetics of photodegradation was also investigated and followed a pseudo-first-order mechanism, with rate constants of 0.0204 min−1 for MG and 0.0123 min−1 for CR in accordance with the Langmuir–Hinshelwood model. The ZnO nanoparticles displayed excellent recycling capability for both dyes and the combined effects of their high adsorption capacity and photodegradation ability of organic dyes make them versatile choice for future applications. [ABSTRACT FROM AUTHOR]

This study aims to synthesize TiO2/ZnO powders and to study the effect of heat treatment on their photocatalytic ability against the Tartrazine anionic dye. The as-obtained powders with the following compositions—90TiO2/10ZnO and 10TiO2/90ZnO (mol%)—were obtained by the sol–gel technique. The prepared gels were annealed at 500 °C and 700 °C and subsequently characterized by XRD, UV–Vis, and SEM methods. The single crystalline phase of TiO2, which has been detected at up to 500 °C is anatase, while for ZnO, it is the hexagonal wurtzite structure. Further increases in the temperature (700 °C) led to the appearance of rutile in the samples. The SEM analysis demonstrated that the binary oxide materials had irregular shaped particles with a tendency to agglomerate. The UV–Vis spectra of the gels exhibited a red shift in the cut-off of the 90TiO2/10ZnO sample compared with pure Ti(IV) butoxide. Photocatalytic tests showed that the investigated samples possessed photocatalytic activity toward Tartrazine. Compared with TiO2, the prepared TiO2/ZnO photocatalysts showed superior properties in the photodegradation of a Tartrazine water solution. The target photocatalysts' enhanced photocatalytic activities can be explained by their reduced band gap energy, improved surface physicochemical characteristics, separation of photo-induced electron–hole pairs, and lowered recombination rate. Higher photocatalytic activity was observed for powders annealed at 500 °C, with the 10TiO2/90ZnO (mol%) sample exhibiting the highest photocatalytic degradation of the used organic dye. [ABSTRACT FROM AUTHOR]

The magnetite-silver nanocomposites (Fe3O4-Ag NCs) were synthesized via a facile and green process by Citrus sinensis peel extract. The deposition of silver nanoparticles (NPs) was confirmed by observing an absorption peak at the maximum wavelength at 422 nm in the suspension solution of samples, which is related to silver surface plasmon resonance (SPR). The characteristic diffraction patterns of Fe3O4 and Ag phases were characterized utilizing the XRD patterns and the average size of the crystals was 21 nm. The photocatalytic behavior of Fe3O4-Ag NCs was studied for the destruction of three organic dyes methyl green (MG), methyl orange (MO), and methylene blue (MB) below UV radiation. The effect of the amount of photocatalyst and volume of hydrogen peroxide as an oxidant in the process of dye degradation was also investigated. The complete degradation time of dyes MB, MG, and MO under UV irradiation in the presence of 0.002 g Fe3O4-Ag NCs were 57, 33, and 49 min, respectively. The time of degradation reactions showed the high photocatalytic performance of Fe3O4-Ag NCs. These results proved that the synergistic effect of magnetite in the role of supporting the silver NPs was a significant contribution to the excellent decolorization behavior of Fe3O4-Ag NCs. [ABSTRACT FROM AUTHOR]

In this study, we aimed to synthesize a zinc-loaded Ziziphus mauritiana seeds activated carbon (Zn/ZMSAC) composite using a hydrothermal technique for the effective removal of Rhodamine B and orange II dye from wastewater. The synthesized Zn/ZMSAC composite was characterized through X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), and transmission electron microscopy (TEM) analyses. This study tackles the issue of organic dye pollution in wastewater by developing a novel composite material with combined photocatalytic and adsorption properties. The Zn/ZMSAC composite proves to be a highly effective and sustainable solution for wastewater treatment. XRD results confirmed the amorphous nature of the Zn/ZMSAC structures. The study demonstrated that the Zn/ZMSAC composite could efficiently remove Rhodamine B and Orange II dyes from aqueous solutions. These findings indicate that the Zn/ZMSAC composite leverages a synergistic interaction between ZnO (acting as photocatalysts) and ZMSAC (functioning as an adsorbent). We propose a potential mechanism for the dye removal process and analyze the kinetics using a pseudo-first-order model. [ABSTRACT FROM AUTHOR]

Organic luminogens play an indispensable role in optoelectronic devices, yet there is a pressing need to address their aggregation‐caused quenching (ACQ) and stability. Here we designed and prepared multilayered boron nitride nanosheets/fluorescein isothiocyanate (MBNNSs/FITC) composite phosphors with tunable photoluminescence by controlling the FITC content and annealing temperature. The research results indicate that MBNNSs/FITC with low or high loading of FITC is not conducive to enhancing the emission intensity of FITC, which can be attributed to the fact that low loading leads to a decrease in the content of fluorescent groups, while high loading promotes intermolecular aggregation of FITC dyes. Interestingly, the emission intensity of FITC in MBNNSs/FITC‐6 composite phosphors can be further enhanced by annealing treatment (200 °C), which can be ascribed to the suppression of the ACQ and effective energy transfer from the MBNNSs to the FITC. Moreover, the resultant composite phosphor displays outstanding thermal stability, remarkable photo stability and exceptional water‐resistance. This work provides a new design space for the development of non‐rare‐earth fluorescent materials using organic fluorescent dyes. [ABSTRACT FROM AUTHOR]

Developing a sustainable security module with multiple optical states is important to deter counterfeits, but is challenging. This work designs a kind of chiral luminescent film through the co‐assembly of the CNCs and d‐glucose, simultaneously doped with the lanthanide complex and organic dye. Superior mechanical performance makes it undertake various deformations, including twist, and tension without breaking. Meanwhile, this film has unique optical characteristics. On the one hand, the chiroptical signals can be manipulated through the matching of the photonic bandgap and fluorescence peak. On the other hand, due to the co‐assembly with two luminophores, the film displays the excitation wavelength (Ex)‐dependent circularly polarized luminescence properties. Under the Ex of 275 nm, the film simultaneously integrates a large dissymmetry factor of −0.3898, a high quantum yield of 69.19%, and a considerable lifetime of 1381 µs, which has exceeded most reported chiral luminescent assemblies. These multimodal and convertible optics endow the film with practical applications in the anti‐counterfeit. It can be designed as a security label or used as a written paper to encrypt the information. Even in humid surroundings, this security effect is still ensured. [ABSTRACT FROM AUTHOR]

Despite the excellent thermometric performance of many developed luminescent nanomaterials, their use has not gone beyond proof‐of‐concept in vivo experiments to date. An important issue that needs to be resolved before moving toward true biomedical applications of engineered nanothermometers is their potential toxicity and bioaccumulation in the human body considering the ultimate objective of clinical applications. Since most reported nanothermometers currently are not degradable materials and are mainly based on the incorporation of heavy metal ions, these aspects remain of genuine concern in the fields of nanomedicine, nanobiotechnology, nanotoxicology, and nanopharmacology. This work explores the possibility of designing visible, as well as near‐infrared, emitting luminescent ratiometric nanothermometers based on appropriate organic dye mixtures embedded in hollow disulfide‐bridged periodic mesoporous organosilica (PMO) particles. Such hybrid particles show excellent thermometric performance in the physiological temperature range (20–50 °C), favorable degradability in simulated physiological conditions, as well as no toxicity to healthy normal human dermal fibroblast (NHDF) cells in a wide concentration range. Considering the simplicity of the approach from the synthetic point of view, and the large available library of known fluorescent dyes emitting in various regions of the electromagnetic range, this motif renders a very promising approach to designing novel non‐toxic, decomposable, luminescent ratiometric thermometers. [ABSTRACT FROM AUTHOR]

Autonomous driving relies on the precise recognition of objects using light detection and ranging (LiDAR) technology, that operates at a specific wavelength of 905 nm. Black objects, such as carbon black used in vehicle coating, tend to absorb this specific wavelength significantly, which limits the performance of LiDAR sensors. To address this issue, researchers have explored creating dark‐toned materials that can be detected by LiDAR with high NIR reflectivity while maintaining a true blackness (L* < 20 based on the CIE color coordinates). These materials fall into two categories: organic and inorganic pigments. Organic pigments can be synthetically adjusted to achieve true blackness by manipulating their functional groups, but achieving high NIR reflectivity remains challenging, often requiring a bilayer structure with NIR‐reflective white base and an upper layer of organic black pigments. Additionally, the need for hydrophobic additives and resistance to degradation from sunlight further restricts their use. In the case of inorganic pigments, the desired LiDAR‐detectable properties can be obtained through careful control of their composition, structure, and morphology, allowing for single‐layer coatings with appropriate design. This review highlights recent advancements in developing organic and inorganic LiDAR‐detectable black pigments and outlines future material design strategies for autonomous vehicle systems. [ABSTRACT FROM AUTHOR]

ABSTRACT The rapid increase of water pollution globally is a vital environmental concern that requires the immediate attention of researchers to find new innovative ways to remove unwanted environmental pollutants from our water sources. With the advances in the field of sustainable engineering, there is a high demand for the effective utilization of biomass resources for the removal of aqueous environmental contaminants. Biochar is carbon carbon‐enriched substance obtained by biomass pyrolysis; it is inexpensive and has received wide attention in the field of wastewater treatment. Herein, we describe the synthesis of pea pod (PO) biochar‐reinforced zeolitic imidazolate framework (ZIF‐8) nanocomposite (PO@ZIF‐8) through the in situ precipitation of ZIF‐8 onto the biochar surface. The crystal growth, morphology, chemical composition, and optical characteristics of fabricated PO@ZIF‐8 nanocomposite were scrutinized through PXRD, SEM, TEM, UV‐DRS, PL, and XPS analysis. The dodecahedral‐shaped PO@ZIF‐8 particles have an average size between 140 and 160 nm. The biochar‐reinforced ZIF‐8 nanocomposite showed significantly higher photocatalytic activity than the pure ZIF‐8 for the degradation of two commonly found organic dyes crystal violet (CV) and Victoria Blue (VB) in the presence of direct sunlight irradiation. The PO@ZIF‐8 nanocomposite showed the highest degradation efficiency of ~87% and ~80% within 50 min of irradiation time at a catalyst dosage of 20 mg for 30 ppm CV and VB dye solutions at pH 8. First‐order kinetics were obeyed during the photodegradation with 0.041 and 0.030 min−1 as the constant of degradation for the removal of CV and VB. The radical scavenger experiment and the photoluminescence analysis confirm the active participation of ·OH radical in the degradation of both dyes. LC–MS and TOC analysis was also performed to determine the degradation products and for evaluation of the degradation progress. Moreover, the synthesized PO@ZIF‐8 composite also exhibit good stability till the fourth cycle with high degradation efficiency thus making it a good choice of catalyst in the field of environmental decontamination. [ABSTRACT FROM AUTHOR]

Fluorescent Carbon Quantum Dots (CQDs) are being used in medical applications, particularly in theranostics. These Carbon Quantum Dots have been gaining more attention lately due to their potential as an effective replacement for hazardous synthetic organic dyes in a variety of biomedical applications, including live cell imaging and diagnostics. In this study, highly fluorescent Carbon Quantum Dots by one pot microwave based green route with a size of less than 10 nm, was prepared from commercially available almond resin, Prunus dulcis and conjugated with honey as additional reagent for surface functionalization. They exhibit a deep blue emission on excitation at 350 nm with an elevated quantum yield at 61%. They possess atomic nature and basic features such as high photo-stability, varying fluorescence, greater biocompatibility, and better water solubility. These fluorescent labels exhibit faster cellular invagination without disturbing the cell stability. The CQDs present cell imaging capacity with multi-coloration for visualizing the fine architecture of the nucleus naming, the nuclear membrane and nucleolus, which is linked with their varied, surface structures such as amphiphilic property and higher positive charges. These characteristics with minimal invasion have made carbon quantum dots to become the spotlight in theranostics. They can be used as alternatives to synthetic dyes for fluorescence- related cell-imaging. The intriguing fact about this approach is that it opens the possibility of combining therapy and diagnostics into one unit, which can alter how some diseases are handled and, in turn, transform the field of healthcare. [ABSTRACT FROM AUTHOR]

Carotenoids are vital organic pigments that determine the color of flowers, roots, and fruits in plants, imparting them yellow, orange, and red hues. This study comprehensively analyzes carotenoid accumulation in different tissues of the Brassica rapa mutant "YB1", which exhibits altered flower and root colors. Integrating physiological and biochemical assessments, transcriptome profiling, and quantitative metabolomics, we examined carotenoid accumulation in the flowers, roots, stems, and seeds of YB1 throughout its growth and development. The results indicated that carotenoids continued to accumulate in the roots and stems of YBI, especially in its cortex, throughout plant growth and development; however, the carotenoid levels in the petals decreased with progression of the flowering stage. In total, 54 carotenoid compounds were identified across tissues, with 30 being unique metabolites. Their levels correlated with the expression pattern of 22 differentially expressed genes related to carotenoid biosynthesis and degradation. Tissue-specific genes, including CCD8 and NCED in flowers and ZEP in the roots and stems, were identified as key regulators of color variations in different plant parts. Additionally, we identified genes in the seeds that regulated the conversion of carotenoids to abscisic acid. In conclusion, this study offers valuable insights into the regulation of carotenoid metabolism in B. rapa, which can guide the selection and breeding of carotenoid-rich varieties. [ABSTRACT FROM AUTHOR]

Novel phase of nano materials that break the traditional structural constraints are highly desirable, particularly in the field of mechanocatalysis, offering versatile applications ranging from energy to medical diagnosis and treatment. In this work, a distinct layered barium dititanate (BaTi2O5) nanocrystals using a pH‐modulated hydrothermal method is successfully synthesized. These nanocrystals exhibit outstanding hydrogen generation capability (1160 µmol g−1 h−1 in pure water) and demonstrate remarkable performance in organic dye degradation using ultrasonication. The crystal structure of this newly discovered BaTi2O5 phase, is determined by a combination of synchrotron Powder Diffraction refinement and X‐ray adsorption techniques, including X‐ray Absorption Near Edge Structure (XANES) and Extended X‐ray Absorption Fine Structure (EXAFS). Density Functional Theory calculations revealed that the newly‐discovered BaTi2O5 phase demonstrates dipole moments along the z‐axis, distributed in an antiparallel direction within a single unit cell. These inherent dipoles induce a surface polarization and a ferroelectric‐flexoelectric response under mechanical stimuli when the materials go to nano dimension. With a band alignment well‐suitable for hydrogen and reactive oxygen species generation, this BaTi2O5 phase demonstrates promising potential for Mechanocatalysis. The discovery of this distinct phase not only enriches the material candidates for mechanocatalysis but also provides valuable insights. [ABSTRACT FROM AUTHOR]

Many organic dyes are fluorescent in solution. In the solid state, however, quenching processes often dominate, hampering material science applications such as light filters, light‐emitting devices, or coding tags. We show that the dimethylene‐cyclopropanide scaffold can be used to form two structurally different types of chromophores, which feature fluorescence quantum yields up to 0.66 in dimethyl sulfoxide and 0.53 in solids. The increased fluorescence in the solid state for compounds bearing malonate substituents instead of dicyanomethide ones is rationalized by the induced twist between the planes of the cyclopropanide core and a pyridine ligand. [ABSTRACT FROM AUTHOR]

In this study, we report the efficient removal of organic dyes from aqueous solutions using a newly synthesized pyrene-appended Zn(II)-based metal–organic framework (MOF), ZnSiF6Pyrene MOF, with the chemical formula C52H32F6N4SiZn·4(CHCl3). The MOF was synthesized through a facile method at room temperature using a dipyridylpyrene ligand and ZnSiF6 metal source, resulting in a highly crystalline structure with pyrene functional groups forming the framework. The synthesized MOF was characterized using various analytical techniques, including Fourier-transform infrared spectroscopy (FT-IR), powder X-ray diffraction (PXRD) analysis, and scanning electron microscopy (SEM). Thermal stability was assessed using thermogravimetric analysis (TGA), while the surface area of the MOF was determined using a Brunauer–Emmett–Teller (BET) surface analyzer. Furthermore, the single-crystal X-ray diffraction (SCXRD) structure was studied to authenticate its solid-state structure. The as-synthesized MOF exhibited remarkable adsorption capacity towards various organic dyes, including Congo red (CR), rhodamine B (RhB), and methyl violet (MV), due to its ample surface area and strong π–π interactions between the pyrene moieties and dye molecules, as demonstrated by experimental and in silico docking studies. The photocatalytic degradation of MV dye was also investigated. Detailed trapping tests indicate that hydroxyl (˙OH) and superoxide (O2˙−) radicals are likely the primary active species responsible for the photodegradation of the dye under study. Furthermore, the photocatalytic property of the MOF was investigated under visible light irradiation, demonstrating excellent ability to generate singlet oxygen. This study highlights the potential of pyrene-appended Zn(II)-based MOFs as promising materials for environmental remediation applications. [ABSTRACT FROM AUTHOR]

This study investigates the degradation of dark blue reactive azo (DBA) dye using the electro-Fenton process, with a focus on real-time colour monitoring to identify the most effective cathode–anode combinations for dye removal. Various electrode materials, including platinum (Pt), carbon fibre (C), silver (Ag), and copper (Cu), were tested. The combinations involving carbon fibre achieved a 75% colour removal within the first 20 minutes of electrolysis, whereas those with Pt electrodes did not exceed 15% in the same timeframe across different combinations. The results indicated that the carbon–copper (C–Cu) electrode combination, under optimized conditions, led to approximately 88% dye removal within 120 minutes. A kinetic study using a non-linear method demonstrated that the degradation followed a first-order kinetic model. To better understand the degradation mechanism, the degradation pathway of the DBA dye was predicted through a theoretical analysis using the Fukui function and supported by UV-Vis absorbance spectra, which revealed potential degradation by-products. The experimental data aligned with the theoretical spectra of potential by-products, confirming the electro-Fenton process's effectiveness in breaking down organic dye molecules. The study highlights the superior performance of carbon-based electrodes compared to platinum electrodes and underscores the importance of electrode material selection in optimizing the electro-Fenton process for dye degradation. [ABSTRACT FROM AUTHOR]

This study introduces an innovative approach by employing a highly sensitive synchronous detection-based dynamic Sénarmont method for the precise measurement of electro-optical (EO) Pockels and Kerr coefficients within hybrid nanocomposite films. The experimental setup integrates LabVIEW instrumentation software, ensuring accurate data acquisition. The EO-active film compositions encompass diverse polymer (PMMA) and organic dye combinations, including PMMA/organic dyes (DR1 and CPO), as well as PMMA combined with DR1-SiC, DR1-TiO2, and CPO-TiO2. Through meticulous experimentation and calibration of the Sénarmont setup, this research demonstrates exceptional sensitivity in evaluating EO parameters based on film composition. Notably, the study examines the impact of poling conditions, geometric configurations, and the influence of TiO2 nanoparticle integration on electro-optical behavior. The findings reveal distinctive electro-optical responses, highlighting the significant potential for tailored designs and practical applications in optimizing polymer nanocomposite electro-optical properties. Overall, this work offers valuable insights into refining measurement techniques and leveraging nanomaterials for enhanced electro-optical functionalities. [ABSTRACT FROM AUTHOR]

Background: Due to it containing cellulose, hemicellulose, and lignin with abundant specific functional groups which could interact with organic dyes, garlic peel (GP) might be used as an efficient biosorbent. The aim of this study is to evaluate the adsorption performances of GP-based bio-adsorbents and obtain optimum preparation conditions. Methods: GP-based bio-adsorbents were prepared by thermal pyrolysis under different temperatures (150–400 °C). The morphologies, chemical states, and surface functional groups of the adsorbents were analyzed by X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), and thermogravimetric analysis (TGA). Batch experiments were conducted to investigate the adsorption of methylene blue (MB) under various conditions, including contact time, contact temperature, initial dye concentration, and initial pH value. The equilibrium adsorption data were fitted to different kinetic and isothermal models, and the adsorption thermodynamics were also calculated. Significant Findings: The physicochemical properties of the GP-based bio-adsorbents were primarily dominated by the pyrolysis temperature, because their morphologies and surface functional groups of GP-based bio-adsorbents significantly varied with the changes in pyrolysis temperature. The adsorption capacity of GP materials for MB decreased as the pyrolysis temperature increased. At an initial concentration of 50.00 mg L−1, GP150 possessed a higher adsorption capacity of 167.74 mg g−1 toward MB. The possible adsorbate–adsorbent interactions, including electrostatic attraction, hydrogen bonding, and π-π stacking, were recognized. After 10 consecutive adsorption–desorption cycles, GP150 maintained a high removal rate (88%) for MB, demonstrating its excellent adsorption performance, good reusability, and potential application in the treatment of MB-contaminated water. [ABSTRACT FROM AUTHOR]

Researchers are keenly interested in developing metal‐based nanoparticles using plant sources as they are eco‐friendly, less expensive and simpler. Zinc oxide nanoparticles, symbolized as D‐ZnONPs and M‐ZnONPs were synthesized in this study utilizing the leaves of D. indica and M. micrantha, respectively, and studied their impact on the growth inhibition of various bacterial strains and on the photocatalysis. By displaying the distinctive surface plasmon resonance (SPR) band at 373 nm in UV‐Vis and bands at 450–480 cm−1 corresponding to Zn−O stretching FTIR spectroscopy imparted the formation of ZnONPs which was further supported by X‐ray diffraction analysis by showing the polycrystalline nature and a hexagonal wurtzite structure. The spherical form and average particle size of 30 nm of the produced ZnONPs, as confirmed by electron microscopy, are also confirmed to be crystalline. Under natural sunlight, both ZnONPs demonstrate excellent degradation efficacy about 96–99 % within 100 min towards methylene blue (MB). Furthermore, it is noteworthy that both the synthesized ZnONPs exhibited 55–60 % efficacy with respect to antibiotics in inhibiting the growth of various pathogenic bacterial strains. Overall, ZnONPs can be produced on a large‐scale using plant sources and employed them in environmental remediation and cosmetic industries as prominent components. [ABSTRACT FROM AUTHOR]

For this study, we investigated the effects of UV illumination on dye decomposition and antibacterial and antiviral activities of three rare earth iodates (Ce(IO3)4, Ce(IO3)3, and δ-La(IO3)3) that reportedly have antibacterial and antiviral activities in the dark. The objective of this study was to clarify whether bulk materials and eluted ions are involved in these activities under UV illumination. Findings indicate that Ce(IO3)3 and δ-La(IO3)3 exhibit dye degradation activity under UV illumination by a Hg-Xe lamp (7 mW/cm2), suggesting that the dye decomposition activity was caused mainly by photochemical reactions under UV with wavelengths less than 300 nm by Ce3+ and by IO3− ions eluted from the samples. The dye decomposition activity under UV illumination is expressed not only from the eluted ions but also from the bulk materials. UV illumination using a weak (0.1 mW/cm2) UV light from a black light bulb with wavelengths longer than 320 nm increased the antibacterial and antiviral activities of these materials. These results suggest that the increase in antibacterial and antiviral activities is attributable to the photocatalytic reaction of bulk materials. This study revealed that both the bulk and eluted ions are involved in these activities under UV illumination. The extent to which photochemical reactions caused by eluted ions and bulk material contribute to the decomposition activity of organic dyes and antibacterial and antiviral activities depends on the UV illumination wavelength and intensity. This study provides new insights into the use of rare earth iodates as inorganic antibacterial and antiviral materials. [ABSTRACT FROM AUTHOR]

In this study, we unveil a novel method for the asymmetric dearomatization of indoles under cobalt/photoredox catalysis. By strategically activating C−H bonds of amides and subsequent migratory insertion of π‐bonds present in indole as reactive partner, we achieve syn‐selective tetrahydro‐5H‐indolo[2,3‐c]isoquinolin‐5‐one derivatives with excellent yields and enantiomeric excesses of up to >99 %. The developed method operates without a metal oxidant, relying solely on oxygen as the oxidant and employing an organic dye as a photocatalyst under irradiation. Control experiments and stoichiometric studies elucidate the reversible nature of the enantiodetermining C−H activation step, albeit not being rate‐determining. This study not only expands the horizon of cobalt‐catalyzed asymmetric C−H bond functionalization, but also showcases the potential synergy between cobalt and photoredox catalysis in enabling asymmetric synthesis of complex molecules. [ABSTRACT FROM AUTHOR]

The present study employed an NH2-MIL-68 (Al) composite for investigating the efficiency of the catalytic ozonation process for degradation of acid blue 113 dye (AB113) from an aqueous media. A facile one-step solvothermal method was used to synthesise NH2-MIL-68 (Al). The effect of varied operational parameters such as pH (3–11), initial dye concentration (20–100 mg/L), catalyst dosage (0.4–2 g/L), and contact time (12–36 min) was optimised via the use of a central composite design (CCD) through response surface methodology (RSM). The results of the study indicated that the highest degradation of the dye was 79.9% at pH (9), initial dye concentration (20 mg/L), catalyst dosage (2 g/L), and contact time (36 min). Additionally, the reusability experiments showed that the efficiency of the process was above 85% after 5 consecutive times of NH2 -MIL-68 (Al) reuse. This research has conclusively highlighted that MIL-68 is a promising potential candidate to remove organic dyes from water and wastewater. [ABSTRACT FROM AUTHOR]

Pollution and the rising energy demand are two major society issues, requiring urgent solutions. Here, we review the simultaneous production of hydrogen and removal of pollutants, with a focus on mechanisms, synthesis of photocatalysts, and applications. Remarkably, this method utilizes organic pollutants as sacrificial agents for photocatalytic hydrogen production, thus both reducing pollution and producing energy. Metal-doped, cocatalyst-loaded, organic and inorganic composite, heterostructure and heterojunction photocatalysts are described. We present applications to the removal of antibiotics and organic dyes. Pollutant degradation rates range from 5.3 to 100%, with hydrogen evolution of 13.7–2724.89 μmol·g–1h–1. [ABSTRACT FROM AUTHOR]

Permanent makeup (PMU) is a popular form of tattooing applied to the eyebrows, eyelids, and lips for corrective and aesthetic purposes. It also has medical applications, such as reconstructing the breast areola, mimicking hair follicles on the head, and covering scars and vitiligo. Unlike body tattoos, PMU often requires reapplication to maintain color density and shape, as the pigments fade over time. This fading is likely due to the characteristics of PMU colorants rather than the application methods or apparatuses. The aim of our study was to assess the application depth of PMU colorants and tattoo ink after procedures. PMU colorants typically contain larger pigment particles in their composition compared to the nanoparticles found in traditional tattoo inks. We applied both tattoo ink and PMU colorants on SKH-1 mice using a PMU apparatus and a tattoo apparatus. To clarify the semi-permanent nature of PMU compared to the more permanent body tattoos, skin biopsies were performed at various intervals throughout this study. The results showed that PMU and tattoo ink were placed at approximately the same depth but exhibited key differences in behavior. PMU with larger inorganic pigments fades over time, while tattoos with smaller, stable organic pigments ensure permanence. [ABSTRACT FROM AUTHOR]

Cellulose derived biochar can be used for adsorbent and photocatalyst mainly because of its good compatibility, high hydrophilicity, and the large amount of electron-rich hydroxy groups. Nevertheless, the impact of the crystal structure of cellulose on the absorption and photocatalytic efficiency of biochar-based composites derived from cellulose remains uncertain. Herein, four different types of biochar derived from cotton (cellulose Iβ, II, III, and IV) were individually impregnated with a TiO2 catalyst through hydrothermal and pyrolysis processes, and were analyzed using various characterization methods. Their adsorption behavior and photocatalytic activities were compared using Congo red and methylene blue dye as the model. The analysis and test outcomes suggested that the crystal structure of cotton cellulose impacted the pore structure and TiO2 content of biochar-TiO2 composites to different degrees, resulting in variations in the adsorption and photocatalytic capabilities of biochar-TiO2 composites. In comparison with cellulose II, III and IV, cellulose I derived biochar-TiO2 composite had a large specific surface area, a more stable structure, a high aromatic carbon content, and a high TiO2 loading, resulting in the strong adsorption ability and superior photoactivity to organic dyes. The adsorption and photocatalysis mechanisms were also clarified. [ABSTRACT FROM AUTHOR]

The catalytic activity of FeCo alloy nanoparticles (NPs) supported on nitrogen-doped mesoporous carbon spheres (FeCo/NMCS) was evaluated for hydrogen evolution and reduction of various organic dyes. The NMCS was spherical, with an average diameter of 488.1 nm, while the FeCo alloy NPs were evenly distributed across the NMCS, with an average diameter of 8.2 nm. The nitrogen content in FeCo/NMCS was found to be 3.91 wt%. The FeCo/NMCS displayed remarkable efficiency in hydrogen evolution through the hydrolysis of ammonia borane (AB), characterized by an activation energy of 23.49 kJ/mol. The FeCo/NMCS also demonstrated superior catalytic activity in reducing 4-nitrophenol (4-NP), with a reduction rate constant of 0.468 min⁻1 using 5 mg of FeCo/NMCS and 20 mg of AB. This rate places the FeCo/NMCS among the highest-performing catalysts for 4-NP reduction. Further, the catalyst efficiently reduced crystal violet, methylene blue, and rhodamine B under the same conditions. Azo dyes, including tartrazine, methyl orange, Red 195, and Yellow 145, underwent faster reduction than other tested dyes. The FeCo/NMCS maintained its integrity and activity even after four hydrogen generation cycles. These results highlight FeCo/NMCS's potential as a multifunctional, magnetically separable, and reusable catalyst for efficient hydrogen production and environmental remediation applications. [ABSTRACT FROM AUTHOR]

In this work, we aimed to demonstrate new polyoxoniobate containing surface peroxo groups obtained after the treatment of niobic acid with hydrogen peroxide and lyophilization process. Raman and diffuse reflectance measurements confirm the presence of peroxo groups in the new polyoxometalate. Isotherms from N2 adsorption/desorption have evidenced a drastic change in specific surface area after treatment with hydrogen peroxide, from 195 m2.g−1 for Nb1 to 4 m2.g−1 for Nb3. Catalytic studies were performed for Congo red (CR) oxidation using H2O2 as oxidizing promoter. The results showed a new material with larger specific area, smaller particle size and an increase in peroxo groups, thus leading to higher catalytic response of discoloration of the Congo red (about 70% for Nb3 and close to 20% for the other catalysts) as compared with the raw material, without previous treatment. [ABSTRACT FROM AUTHOR]

Minimally invasive surgery continues to prioritize patient safety by improving imaging techniques and tumor detection methods. In this work, an all-optical alternative to the current image based techniques for in vitro minimally invasive procedures has been explored. The technique uses a highly fluorescent marker for the surgical needle to be tracked inside simulated tissues. A series of markers were explored including inorganic (Perovskite and PbS) and organic (carbon dots) nanoparticles and organic dye (Rhodamine 6G) to identify layers of different stiffnesses within a tissue. Rhodamine 6G was chosen based on its high fluorescence signal to track 3D position of a surgical needle in a tissue. The needle was tracked inside homogeneous and inhomogeneous gelatin tissues successfully. This exploratory study of tissue characterization and needle tip tracking using fluorescent markers or photoluminescence technique show potential for real-time application of robot-assisted needle insertions during in vivo procedures. [ABSTRACT FROM AUTHOR]

The two technologies of dye-sensitized solar cells (DSSCs) and organic light-emitting devices (OLEDs) are emerging in the development of new sources of energy and lighting, respectively. The exceptional features of these technologies, including their color, insensitivity to temperature, and high response angle, have caused their attention and development. Organic compounds play a key role in these two technologies and cause the effective response and stability of the device, so high stability, longevity, and the possibility of simple application in the structure of the structure are of great importance. Molecular engineering and the application of various substitutions to the naphthalimide core can produce promising results for the preparation of stable organic materials with diversity in properties. In this review, naphthalimides are introduced as an effective core in the preparation of lightand electricity-sensitive dyes. Its application in two technologies, DSSCs and OLED, is explained, and the different components of these technologies are briefly introduced. One of the highest efficiencies reported for dye-sensitized solar cells based on naphthalimide as photosensitizers is 10.8 %. This sensitizer has alkyl and indoline groups. Different structures of arrangement of electron donor and electron acceptor groups will be investigated and the performance efficiency of these devices will also be investigated. Studies show that the amino group is an important substitution in the preparation of naphthalamide fluorescent dyes. The presence of this group will increase the efficiency of the amplifier by up to 10 %. [ABSTRACT FROM AUTHOR]

This review focuses mostly on organic dye‐sensitized solar cells, as they are an attractive, environmentally friendly alternative to traditional silicon solar cells for the production of renewable energy at a lower cost. The dye chromophore is recognized as the central component of the DSSC device. To improve the electrochemical, photovoltaic, and absorption properties of organic sensitizing dyes, we have designed a series of eight new dyes Pi (i = 1.8) based on the DPA‐2 architecture (the reference molecule). We have investigated the effects of internal absorption of different acceptor groups in D‐Ai‐π‐A before and after binding to the TiO2 cluster surface on the ability to inject electrons into the surface. The benzophenothiazine is the D donor, the π‐spacer is furan, and the A acceptor is cycnoacrylic acid. We are using time‐dependent density functional theory (TD‐DFT), and density functional theory (DFT) in our quantum calculations. It is theoretically possible to predict suitable candidates for the DSSC device and identify correlations between their structure and properties by using DFT and TD‐DFT simulations to thoroughly study in detail electronic structures, natural binding orbital (NBO), analysis of UV‐visible absorption spectra, parameters influencing short‐circuit current density (JSC), open‐circuit voltage (VOC), and intramolecular charge transfer (ICT). Additionally, the relationship between optoelectronic properties and molecular structure was investigated, and the effect of auxiliary acceptor groups (Ai) on the primary photovoltaic properties of the reference molecule DPA‐2. The results show that by changing the internal acceptor to DPA‐2 could create a more coplanar and rigid structure. This would cause the energy gap (Eg) for each of the dyes created to significantly shrink, reducing it from 2.29 to 1.38 eV. The absorption spectra's λmax for each dye would also change color, this was because the acceptor moiety Ai of the phenothiazine moiety changed when it came to DPA‐2 (not including compounds P1 and P4). In contrast, P6 and P7 dyes demonstrate an absorption range beyond 500 nm, implying a more efficient utilization of sunlight in the visible spectrum compared to other dyes. Furthermore, all organic dyes show a robust LHE performance (0.919 to 0.993), correlating with the lowest ΔGreg values (0.097 to 0.356) and the most negative ΔGinject values (−2.067 to −1.121). The power conversion efficiency of PCE and JSC could increase according to these results. Therefore, theoretical research into adding a second internal acceptor group to the D‐Ai‐π‐A structure should produce new methods for improving solar energy output. [ABSTRACT FROM AUTHOR]

Organic dyes derived from industrial processes have harmful potential to aquatic systems and require novel oxidative treatment. Metal‐organic frameworks (MOF) couple high adsorption capacity and photocatalytic action, which can be improved through heterojunctions. In this work, CuBTC (MOF) photocatalyst was synthesized by an electrochemical methodology, and the in situ CuS templated formation by addition of Na2S solution, giving CuBTC/CuS composites. The synthesized CuBTC MOF and CuBTC/CuS composites were characterized by XRD, FTIR, TGA, and EDX. The adsorptive capacity and photocatalytic properties were evaluated by the photocatalytic performance against methylene blue (MB) aqueous solution, under dark and simulated solar irradiation. Under simulated solar irradiation, the CuBTC/CuS achieved 87 % dye photodegradation after 120 min, 1.7 times higher than CuBTC. The photocatalytic action mechanisms were investigated by free‐radical capture experiments. At the equilibrium, the photocatalytic process presented pseudo‐first‐order (PFO) and pseudo‐second‐order (PSO) non‐linear kinetic models, showing a higher correlation with the PFO model, with a rate constant of 94.3×10−3 min−1. The photocatalytic performance of the composite was also evaluated over five cycles, decreasing to 68 %. The proposed strategy showed promise for the developing of highly effective materials to combat water pollution. [ABSTRACT FROM AUTHOR]

This study aims to elucidate the possible application of cobalt aluminate nanoparticles (CoAl 2 O 4) as a photocatalyst for the removal of organic dyes. The sol-gel method was employed to synthesise Nd x /CoAl 2 O 4 nanoparticles with varying weight percentages (x = 0.0, 0.2, 0.4, and 0.6 wt %). The experimental investigation focused on the photocatalytic destruction of colour, employing a visible light irradiation source. The structural and optical properties of the synthesised nanoparticle were examined through various analytical techniques, including X-Ray Diffraction (XRD), Ultra Violet-Diffuse Reflectance Spectroscopy (UV-DRS), Scanning Electron Microscopy (SEM), Energy-Dispersive X-ray spectroscopy (EDX), Tunnelling Electron Microscopy (TEM), and X-ray Photoelectron Spectroscopy (XPS). The cubic spinel structure was confirmed through the study of the X-ray diffraction (XRD) pattern of the Nd x /CoAl 2 O 4 nanoparticles. For the compositions x = 0.0, 0.2, 0.4, and 0.6, the nanoparticles exhibited average crystallite sizes of 23.73, 22.99, 21.69, and 21.65 nm, respectively. The synthesised nanoparticle exhibited heterogeneous photocatalytic potential when employed as a model pollutant for the oxidative destruction of crystal violet dye. The experimental findings validated that the CoAl 2 O 4 nanoparticle exhibited a dye degradation rate of 64 % during a 100-min timeframe. Additionally, the 0.6 wt % Nd CoAl 2 O 4 nanoparticle shows a quick dye degradation rate of 91 % for crystal violet dyes when exposed to visible light sources. Hence, the synthesised nanoparticle exhibits catalytic activity and holds potential for utilisation in the treatment of hazardous contaminants in industrial wastewater. [ABSTRACT FROM AUTHOR]