The Effect of Conjugated Nitrile Structures as Acceptor Moieties on the Photovoltaic Properties of Dye-Sensitized Solar Cells: DFT and TD-DFT Investigation.

A major challenge in improving the overall efficiency of dye-sensitized solar cells is improving the optoelectronic properties of small molecule acceptors. This work primarily investigated the effects of conjugation in nitriles incorporated as acceptor moieties into a newly designed series of D-A-A dyes. Density functional theory was employed to specifically study how single-double and single-triple conjugation in nitriles alters the optical and electronic properties of these dyes. The Cy-4c dye with a highly conjugated nitrile unit attained the smallest band gap (1.80 eV), even smaller than that of the strong cyanacrylic anchor group (2.07 eV). The dyes lacking conjugation in nitrile groups did not contribute to the LUMO, while LUMOs extended from donors to conjugated nitrile components, facilitating intramolecular charge transfer and causing a strong bind to the film surface. Density of state analysis revealed a considerable impact of conjugated nitrile on the electronic properties of dyes through an effective contribution in the LUMO, exceeding the role of the well-known strong 2,1,3-benzothiadiazole acceptor unit. The excited state properties and the absorption spectra were investigated using time-dependent density functional theory (TD-DFT). Conjugation in the nitrile unit caused the absorption band to broaden, strengthen, and shift toward the near-infrared region. The proposed dyes also showed optimum photovoltaic properties; all dyes possess high light-harvesting efficiency (LHE) values, specifically 96% for the dyes Cy-3b and Cy-4c, which had the most conjugated nitrile moieties. The dyes with higher degrees of conjugation had longer excitation lifetime values, which promote charge transfer by causing steady charge recombination at the interface. These findings may provide new insights into the structure of conjugated nitriles and their function as acceptor moieties in DSSCS, which may lead to the development of extremely effective photosensitizers for solar cells.

Synthesis of polymeric 2D-graphitic carbon nitride (g-C3N4) nanosheets for sustainable photodegradation of organic pollutants.

A superficial, one step thermal polycondensation method has been employed for the manifestation of graphene like graphitic carbon nitride (g-C3N4) catalyst. The as synthesized g-C3N4 was well characterized by SEM and EDAX analysis, XRD, ATR-IR, FTIR, Fluorescence spectroscopy, Raman spectroscopy and UV-Visible spectroscopy which provide structural, morphological assemblage relating to the structure of g-C3N4. The g-C3N4 showed that an outstanding photochemical stability, morphology, conductive carbon framework and superior photocatalytic activity. The band gap value of g-C3N4 is 2.34 eV determined using Tauc plot. Due to low band gap (2.33 eV) and unique morphology which provides high separation and migration ability of the photogenerated charges, the g-C3N4 shows enhanced photocatalytic activity for the removal of many organic dyes such as Rhodamine B (RhB), Crystal Violet (CV), Methylene Blue (MB), Methyl Orange (MO), Naphthol Orange (NO) and a phenol derivative, p-Nitrophenol (p-NP). Among them, RhB dye was degraded almost 81 % at 90 min under sunlight irradiation in presence g-C3N4 while other dyes and p-NP was degraded at lower rate. From the experimental data, it was found that MO and p-NP degradation rate was least. The rate constant for degradation of Rh B is 1.1 × 10-2 min-1. Therefore, g-C3N4 can be used as an efficient photocatalyst for waste water treatment by the removal of such organic pollutants.

J-aggregates of strong electron-donating groups linked Aza-BODIPY adjusting by polypeptide for NIR-II phototheranostics.

The commonly employed strategies for engineering second near-infrared (NIR-II) organic phototheranostic agents are based on expanding conjugated backbone length, strengthening donor (D)-acceptor (A) effect, or forming J-aggregates. We constructed the D-A-D' structure by incorporating strong electron-donating methoxy and tetraphenylethene (TPE) moieties on the electron-deficient Aza-BODIPY core, and simultaneously expanded the π-conjugation effect by introducing thiophene groups, to obtain a dye BDP-TPE. Next, the nanoparticles P-TPE were prepared via the assembly of BDP-TPE with amphiphilic polypeptides (mPEG2000-P(Asp)10), and successfully constructed the J-aggregates. The obtained P-TPE exhibited strong absorption and fluorescence with maxima at 808 and 1018 nm, respectively, with a conspicuous absolute quantum yield of 0.241 %. Moreover, P-TPE also showed excellent biocompatibility, and high photothermal conversion efficiency of 61.15 %, and excellent resistance to pH, long-term storage, and photobleaching. In vitro and in vivo experiments revealed that P-TPE exhibited good biocompatibility and effectively achieved NIR-II fluorescence imaging-guided PTT with complete tumor ablation under 808 nm laser irradiation. These results provided good evidence for the use of P-TPE as a NIR-II fluorescence imaging-guided PTT therapeutic agent in vivo.

A novel nano-cerium oxide functionalized biochar composite for degradation of organic dye: insight of the photocatalysis mechanism.

Recently, visible-light-driven photocatalysis attracts much concerns in the remediation of environmental organic pollutants. In this study, the cerium doped biochar was fabricated through the hydrothermal method, and served as an efficient photocatalyst towards rhodamine B degradation under visible light irradiation. Almost 100% of rhodamine B was removed by 2.0 g·L-1 cerium doped biochar after 60 min of visible light irradiation at pH 3, but only about 25.50% and 29.60% of rhodamine B was removed by cerium dioxide and biochar under identical conditions. The degradation process coincided well with the pseudo-first-order kinetic model, and the photodegradation rate constant of cerium doped biochar was 0.0485·min-1, which was respectively 97 and 44 times that of biochar (0.0005·min-1) and cerium dioxide (0.0011·min-1). According to the trapping experiments and electron spin resonance spectroscopy analysis, h+, O2-∙ and ∙OH all participated in the degradation of rhodamine B in the cerium doped biochar photocatalytic systems, and the function of h+ and ∙OH was dominated. Consequently, the biochar could not only be an excellent carrier for supporting cerium dioxide, but also greatly improved its photocatalytic activity. The band gap of cerium doped biochar was narrower than cerium dioxide, which could improve the separation and migration of photogenerated electron-hole pairs under visible-light excitation, thus ultimately enhanced the degradation of rhodamine B. This work provided a deeper understanding of the preparation of biochar-based photocatalyst and its application in the remediation of environmental organic pollution.

Biocompatible and Water-Soluble Shortwave-Infrared (SWIR)-Emitting Cyanine-Based Fluorescent Probes for In Vivo Multiplexed Molecular Imaging.

Extending molecular imaging into the shortwave-infrared (SWIR, 900-1400 nm) region provides deep tissue visualization of biomolecules in the living system resulting from the low tissue autofluorescence and scattering. Looking at the Food and Drug Administration-approved and clinical trial near-infrared (NIR) probes, only indocyanine green (ICG) and its analogues have been approved for biomedical applications. Excitation wavelength less than 800 nm limits these probes from deep tissue penetration and noninvasive fluorescence imaging. Herein, we present the synthesis of ICG-based π-conjugation-extended cyanine dyes, ICG-C9 and ICG-C11 as biocompatible, and water-soluble SWIR-emitting probes with emission wavelengths of 922 and 1010 nm in water, respectively. Also, ICG-, ICG-C9-, and ICG-C11-based fluorescent labeling agents have been synthesized for the development of SWIR molecular imaging probes. Using the fluorescence of ICG, ICG-C9, and ICG-C11, we demonstrate three-color SWIR fluorescence imaging of breast tumors by visualizing surface receptors (EGFR and HER2) and tumor vasculature in living mice. Furthermore, we demonstrate two-color SWIR fluorescence imaging of breast tumor apoptosis using an ICG-conjugated anticancer drug, Kadcyla and ICG-C9 or ICG-C11-conjugated annexin V. Finally, we show long-term (38 days) SWIR fluorescence imaging of breast tumor shrinkage induced by Kadcyla. This study provides a general strategy for multiplexed fluorescence molecular imaging with biocompatible and water-soluble SWIR-emitting cyanine probes.

Removal of Methylene Blue Dye from Aqueous Solutions Using Polymer Inclusion Membrane Containing Calix[4]pyrrole.

The effective purification of aqueous solutions of methylene blue dye was tested using polymer inclusion membranes (PIMs) that contained cellulose triacetate (CTA) as a polymer base, o-nitrophenyl octyl ether (o-NPOE) as a plasticizer, and meso-tetra methyl tetrakis-[methyl-2-(4-acetlphenoxy)] calix[4]pyrrole (KP) as a carrier. Scanning electron microscopy (SEM), thermogravimetric analysis (TGA), and attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy were used to define the microstructure and surface of PIMs. Experimental results showed that, with an increased concentration of methylene blue in an aqueous solution, the removal percentage also increased. Further observation showed that the flux increased with the rise in the source phase pH values from 3 to 10. The carrier and plasticizer content in the membrane significantly influenced the membrane's transport properties. The optimal composition of the membrane in percent by weight for KP was 74% plasticizer; 18% support, and 8% carrier. The maximum MB removal (93.10%) was achieved at 0.10 M HCl solution as the receiving phase. It was shown that the membrane with optimal composition showed good reusability and enabled the easy and spontaneous separation of methylene blue from aqueous solutions.

Remarkable purification of organic dyes by NiOOH-modified industrial waste residues.

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.

Anodizing Tungsten Foil with Ionic Liquids for Enhanced Photoelectrochemical Applications.

This research examines the influence of adding a commercial ionic liquid to the electrolyte during the electrochemical anodization of tungsten for the fabrication of WO3 nanostructures for photoelectrochemical applications. An aqueous electrolyte composed of 1.5 M methanesulfonic acid and 5% v/v [BMIM][BF4] or [EMIM][BF4] was used. A nanostructure synthesized in an ionic-liquid-free electrolyte was taken as a reference. Morphological and structural studies of the nanostructures were performed via field emission scanning electron microscopy and X-ray diffraction analyses. Electrochemical characterization was carried out using electrochemical impedance spectroscopy and a Mott-Schottky analysis. From the results, it is highlighted that, by adding either of the two ionic liquids to the electrolyte, well-defined WO3 nanoplates with improved morphological, structural, and electrochemical properties are obtained compared to samples synthesized without ionic liquid. In order to evaluate their photoelectrocatalytic performance, the samples were used as photocatalysts to generate hydrogen by splitting water molecules and in the photoelectrochemical degradation of methyl red dye. In both applications, the nanostructures synthesized with the addition of either of the ionic liquids showed a better performance. These findings confirm the suitability of ionic liquids, such as [BMIM][BF4] and [EMIM][BF4], for the synthesis of highly efficient photoelectrocatalysts via electrochemical anodization.

Synergistic potential in spinel ferrite MFe2O4 (M = Co, Ni) nanoparticles-mediated graphene oxide: Structural aspects, photocatalytic, and kinetic studies.

The existence of artificial dyes in water is a significant environmental concern, as it can lead to poor water quality. Photodegradation is becoming an increasingly popular method for treating water contaminated with dyes. In this study, the photodegradation of Reactive Red 66 and Reactive Red 120 dyes, as well as textile wastewater, was investigated under UV and visible light irradiation. To enhance the photoresponse of the MFe2O4 (M = Co, Ni) nanoparticles, modifications were made by incorporating graphene oxide. The MFe2O4 nanoparticles and MFe2O4/GO nanocomposite photocatalysts were subjected to several characterization techniques, including FT-IR, Raman spectroscopy, XRD, DRS, zeta potential, VSM, TGA, DSC, BET, SEM, and EDAX analysis. Experiments were conducted to optimize several key parameters involved in the photodegradation process, including pH, photocatalyst dosage, initial dye concentration, and irradiation time. The removal efficiency of Reactive Red 66 and Reactive Red 120 dyes using CoFe2O4 nanoparticles was found to be 86.97 and 82.63%, respectively. Also, the removal percentage of these dyes using CoFe2O4/GO nanocomposite photocatalyst was 95.57 and 90.9% for Reactive Red 66 and Reactive Red 120, respectively. Experiments found that NiFe2O4 nanoparticles removed 90.92% of Reactive Red 66 dye and 84.7% of Reactive Red 120 dye. The NiFe2O4/GO nanocomposite photocatalyst showed even higher removal efficiencies, degrading 97.96% of Reactive Red 66 and 93.44% of Reactive Red 120. After three days of exposure to visible light irradiation, the removal percentage of Reactive Red 66 using MFe2O4 and MFe2O4/GO nanocomposite was investigated.

Enhanced photocatalytic degradation of Rhodamine B using gold nanoparticles decorated on BaTiO3 with surface plasmon resonance enhancement.

This study focused on synthesizing and applying gold nanoparticle (Au NP) decorated barium titanate (BaTiO3) nanoparticles for photocatalytic purposes. BaTiO3 NPs were synthesized using a facile hydrothermal method. Various techniques were employed to characterize the structure and morphological characteristics of the prepared materials. The photocatalytic degradation of Rhodamine B over the Au NPs-modified BaTiO3 photocatalysts was studied. Trapping experiments were conducted using different scavengers to elucidate the degradation mechanism and the involvement of photogenerated species. The incorporation of an appropriate amount of Au NPs into the composites resulted in a significant improvement in photocatalytic activity, attributed to the combined effect of Schottky junction at the interface and the surface plasmon resonance of Au NPs.

Tuning the Topology of Two-Dimensional Covalent Organic Frameworks through Site-Selective Synthetic Strategy.

Tuning the topology of two-dimensional (2D) covalent organic frameworks (COFs) is of paramount scientific interest but remains largely unexplored. Herein, we present a site-selective synthetic strategy that enables the tuning of 2D COF topology by simply adjusting the molar ratio of an amine-functionalized dihydrazide monomer (NH2 -Ah) and 4,4',4''-(1,3,5-triazine-2,4,6-triyl)tribenzaldehyde (Tz). This approach resulted in the formation of two distinct COFs: a clover-like 2D COF with free amine groups (NH2 -Ah-Tz) and a honeycomb-like COF without amine groups (Ah-Tz). Both COFs exhibited good crystallinity and moderate porosity. Remarkably, the clover-shaped NH2 -Ah-Tz COF, with abundant free amine groups, displayed significantly enhanced adsorption capacities toward crystal violet (CV, 261 mg/g) and congo red (CR, 1560 mg/g) compared to the non-functionalized honeycomb-like Ah-Tz COF (123 mg/g for CV and 1340 mg/g for CR), underscoring the pivotal role of free amine functional groups in enhancing adsorption capacities for organic dyes. This work highlights that the site-selective synthetic strategy paves a new avenue for manipulating 2D COF topology by adjusting the monomer feeding ratio, thereby modulating their adsorption performances toward organic dyes.

Organic Dye Molecule Intercalated Vanadium Oxygen Hydrate Enables High-Performance Aqueous Zinc-Ion Storage.

Although the layered vanadium oxide-based materials have been considered to be one of the candidates for aqueous Zn-ion batteries (AZIBs), it still faces inevitable challenges of unsatisfactory capacities and sluggish kinetics because of strong electrostatic interactions between Zn-ions and structure lattice. This work addresses the strategy of pre-inserting guest materials to vanadium oxide cathode using different intercalants. To achieve this goal, the small organic dye molecules, methyl orange (MO), and methylene blue (MB) are proposed as the intercalants for vanadium oxygen hydrate (VOH). It has been demonstrated that use of these intercalants can facilitate reaction kinetics between Zn2+ and VOH, leading to an improvement of specific capacity (293 mAh g-1 at 0.3 A g-1 for MO-VOH and 311 mAh g-1 for MB-VOH) compared to VOH, a large enhancement of excellent energy density (237.1 Wh kg-1 for MO-VOH, 232.3 Wh kg-1 for MB-VOH), and a prolong lifespan operation at 3 A g-1 . The mechanism studies suggest that the weakened electrostatic interactions between the Zn-ions and V-O lattice after intercalating organic molecules contribute to boosting the electrochemical performance of AZIBs unveiled by charge density difference and binding energy.

Preparation of porous silica materials using a eucalyptus template method and its efficient adsorption of methylene blue.

Methylene blue (MB) is a prevalent pollutant in organic wastewater. For this research, eucalyptus wood was used as a template, into which quartz powder dissolved in NaOH was grown, resulting in a low-cost and efficient porous silica adsorbent material (PSAM). This PSAM successfully replaces expensive materials for MB removal from water. Through the application of Scanning Electron Microscopy (SEM) and Brunauer-Emmett-Teller (BET) analysis, it became evident that PSAM displays a porous slit pore structure characterized by numerous active sites, leading to an impressive maximum specific surface area of 88.05 m²/g. The central objective of this research was to investigate the impact of experimental temperature, initial dye concentration, and pH on the adsorption process. The adsorption kinetics were analyzed using the pseudo-first-order and pseudo-second-order models, as well as the Langmuir model. Remarkably, PSAM exhibited a substantial maximum adsorption capacity of 90.01 mg/g at 293 K, achieving an adsorption rate of over 85% within a mere 10-minute timeframe. The thermodynamic analysis revealed that the adsorption of MB onto PSAM was characterized by spontaneity and accompanied by heat absorption. Fourier Transform Infrared (FTIR) and SEM comparisons of PSAM before and after adsorption indicated that MB adsorption primarily occurred through electrostatic gravitational binding. In comparison to other adsorbents, PSAM exhibited exceptional efficacy in removing MB from water.

Biosynthesis of gold nanoparticles by Penicillium rubens and catalytic detoxification of ochratoxin A and organic dye pollutants / Biosíntesis de nanopartículas de oro por Penicillium rubens y desintoxicación catalítica de ocratoxina A y contaminantes colorantes orgánicos

The environmental pollution caused by chemical dyes is a growing concern nowadays. Limitations of traditional methods opened the route for nanotechnology; owing to the versatile properties of nanomaterials, gold nanoparticles (AuNPs) became a potential strategy for different applications. In the present study, biosynthesis of gold nanoparticles (BioAuNPs) was carried out by reacting chloroauric acid (HAuCl4) with cell-free filtrate of Penicillium rubens sp. nov. NCIM 1937. The AuNPs were then characterized by UV–visible spectroscopy, HR-TEM, FTIR, and DLS analysis to further examine their efficacious biosynthesis and morphological properties including size, shape, and stability. The biogenic AuNPs are polydisperse in nature, with a mean size of 14.92 ± 5 nm. These AuNPs exhibited promising antimicrobial activity against Escherichia coli NCIM-2065, Bacillus subtilis NCIM-2010, and Penicillium verrucosum MTCC 4935. In vitro quantitative HPLC results revealed that BioAuNPs significantly inhibited the biosynthesis of ochratoxin A (OTA). Microbial fuel cells (MFCs) are intriguing for power generation and wastewater treatment since they can directly transform chemical energy stored in organic matter to electricity by extracellular electron transfer (EET) via membrane proteins. AuNPs also showed excellent potential for dye degradation of organic pollutants, viz., methylene blue (MB), phenol red (PR), bromothymol blue (BTB), Congo red (CR), and 4-nitrophenol (4-NP). All dye removal efficiencies were estimated and fitted to pseudo-first-order processes using kinetic rate constants (Ka).The present study reveals a simple, original, and eco-friendly method for the synthesis of multifunctional biogenic AuNPs that could be effective in OTA detoxification in food products and organic pollutant removal during wastewater treatment for a sustainable environment.(AU)

Molecular Engineering of Photosensitizers for Solid-State Dye-Sensitized Solar Cells: Recent Developments and Perspectives.

Dye-sensitized solar cells (DSSCs) are a feasible alternative to traditional silicon-based solar cells because of their low cost, eco-friendliness, flexibility, and acceptable device efficiency. In recent years, solid-state DSSCs (ss-DSSCs) have garnered much interest as they can overcome the leakage and evaporation issues of liquid electrolyte systems. However, the poor morphology of solid electrolytes and their interface with photoanodes can minimize the device performance. The photosensitizer/dye is a critical component of ss-DSSCs and plays a vital role in the device's overall performance. In this review, we summarize recent developments and performance of photosensitizers, including mono- and co-sensitization of ruthenium, porphyrin, and metal-free organic dyes under 1 sun and ambient/artificial light conditions. We also discuss the various requirements that efficient photosensitizers should satisfy and provide an overview of their historical development over the years.

Surface Modification of ZnO with Sn(IV)-Porphyrin for Enhanced Visible Light Photocatalytic Degradation of Amaranth Dye.

Two hybrid composite photocatalysts, denoted as SnP/AA@ZnO and SnP@ZnO, were fabricated by a reaction of trans-dihydroxo[5,10,15,20-tetrakis(4-pyridyl)porphyrinato]tin(IV) (SnP) and ZnO with and without pretreatment of adipic acid (AA), respectively. In SnP@ZnO, SnP and ZnO are likely held together by a coordinative interaction between the pyridyl N atoms of SnP and the Zn atoms on the surface of ZnO. In the case of SnP/AA@ZnO, the SnP centers were robustly coupled with ZnO nanoparticles through the AA anchors. SnP/AA@ZnO exhibited largely enhanced photocatalytic activities for the degradation of anionic amaranth (AM) dye under a visible light irradiation, compared to SnP, ZnO, and SnP@ZnO. The degradation efficiency of AM by SnP/AA@ZnO was 95% within 60 min at a rate constant of 0.048 min-1. The remarkable photocatalytic oxidation performance of SnP/AA@ZnO was mainly attributed to the synergistic effect between SnP and ZnO. This study is valuable for the development of highly effective composite photocatalytic systems in advanced oxidation processes and is of importance for the treatment of wastewater containing dyes.

Magnetic nanocellulose-based adsorbent for highly selective removal of malachite green from mixed dye solution.

Herein, a novel magnetic adsorbent (BC/AA/MN@Fe3O4) was successfully prepared from waste bamboo fiber tissue and montmorillonite, and subsequently applied for the highly selective removal of malachite green (MG, removal efficiency = 97.3 %) from the mixed dye solution of MG with methyl orange (MO, removal efficiency = 4.5 %). The magnetic adsorbent has a high porosity with abundant mesopores. In the single dye MG solution, the adsorbent could effectively remove MG over a wide pH range from 4 to 10, and the maximum adsorption capacity (qmax) was 2282.3 mg/g. Moreover, the magnetic adsorbent could remove MG from various solutions including mixed dye solution, high salinity solution, and real river water dye solution. The thermodynamic results proved that the adsorption process of MG was spontaneous and endothermic. The adsorption of MG was due to the comprehensive effects of electrostatic attraction, hydrogen bonding interactions and ions exchange, between the adsorbent and MG. Furthermore, the BC/AA/MN@Fe3O4 exhibited an excellent reusability with adsorption efficiency above 53.4 % after five consecutive cycles. Therefore, the prepared magnetic nanocellulose-based adsorbent was expected to be a promising material for highly selective adsorption and separation of MG from mixed dye solution.

A Detailed Insight into the Effects of Morphologies of Cerium Oxide on Fenton-like Reactions for Different Applications.

As an exceptional Fenton-like reagent, cerium oxide (CeO2 ) finds applications in biomedical science and organic pollutants treatment. The Fenton-like reaction catalyzed by CeO2 typically encompasses two distinct processes: one resembling the classical Fenton reaction, wherein cerium (Ce3+ ) triggers the decomposition of hydrogen peroxide (H2 O2 ) to yield reactive oxygen species (ROS), and the other involves the complexation of H2 O2 on the Ce3+ surface, leading to the formation of peroxides. However, the influence of diverse CeO2 morphologies on these two reaction pathways has not been comprehensively explored. In this study, CeO2 exhibiting three typical morphologies, rods, cubes, and spheres, were prepared. The generation of ROS and peroxides was evaluated using the 3,3,5,5-tetramethylbenzidine (TMB) oxidation reaction and the reduction current of H2 O2 , respectively. Moreover, the impacts of pH variations and CeO2 /H2 O2 concentrations on the production and conversion of these two reaction products were investigated. To corroborate the distinctions between the resultant products and their applicability, apoptosis assays and acid orange 7 (AO7) degradation analyses were performed. Notably, CeO2 rods exhibited the highest proportion of Ce3+ , predominantly engaging in complexation with H2 O2 to foster peroxide formation, thereby facilitating the robust degradation of AO7. However, the generated peroxides appeared to occupy Ce3+ sites, thereby impeding the H2 O2 decomposition process. Conversely, Ce3+ species on the surface of CeO2 cubes were primarily involved in H2 O2 decomposition, leading to heightened ROS production, and thus showcasing substantial potential for damaging A549 tumor cells. It is worth noting that the ability of these Ce3+ species to form peroxides through complexation with H2 O2 was comparatively reduced. In summation, this study sheds light on the intricate interplay between distinct CeO2 morphologies and their divergent impacts on Fenton-like reactions. These findings expand our comprehension of the influences on its reactivity of CeO2 morphologies and open new insights for applications in diverse domains, from organic dye degradation to tumor therapy.

Treating waste with waste: Adsorption of anionic dyes in wastewater with surfactant-modified phosphogypsum.

Phosphogypsum (PG) is a solid waste generated during the wet process of phosphoric acid production. The environmental-friendly disposal and recycling of PG is vital in the field of environmental solid waste treatment. In this study, PG is used for adsorbent of dyes in wastewater to achieve the goal of recycling waste with waste. Surfactant-modified phosphogypsum (ODBAC@PG) was prepared using octadecyl dimethyl benzyl ammonium chloride (ODBAC) as modifier. ODBAC@PG exhibits high adsorption capability for anionic dyes (methyl blue (MeB) and indocyanine carmine (IC)). The pseudo-second-order kinetic model fits the kinetic experimental data for the adsorption of two organic anionic dyes. Langmuir adsorption isotherm fits the adsorption characteristics of MeB and IC on ODBAC@PG, exhibiting a monolayer adsorption pattern. Thermodynamic parameters indicate the spontaneous and exothermic properties of MeB and IC on ODBAC@PG. MeB and IC have antagonistic effects on each other in binary adsorption system. High adsorption capacity after six cycles of experiments demonstrates the high reusability of ODBAC@PG. The nature for the adsorption includes electrostatic interaction, hydrogen bond and hydrophobic interaction. Using ODBAC@PG for dyes wastewater treatment can accomplish the goal of treating waste with waste and turning waste into treasure.

D-π-A Structured Porphyrin and Organic Dyes with Easily Synthesizable Donor Units for Low-Cost and Efficient Dye-Sensitized Solar Cells.

This study aimed to develop low-cost D-π-A structured porphyrin and organic dyes with easily synthesizable donor units instead of the conventional complex multistep synthetic donor unit of Hexyloxy-BPFA [bis(7-(2,4-bis(hexyloxy)phenyl)-9,9-dimethyl-9H-fluoren-2-yl)amine] used in SGT-021 and SGT-149 as well-known record cosensitizers with an extremely high power conversion efficiency (PCE). The design strategy concerned the easier synthesis of low-cost donor units with inversion structures in donor groups via donor structural engineering, particularly by changing the position of the fluorene and phenylene units in the donor moiety while keeping the π-bridge and acceptor unit unchanged, leading to the synthesis of two D-π-A structured porphyrins [SGT-021(D0) and SGT-021(D)] and one D-π-A structured organic sensitizer [SGT-149(D)] for dye-sensitized solar cells (DSSCs). Specifically, porphyrin SGT-021(D0) incorporated two hexyl chains into the 9-position of each fluorene, while SGT-021(D) and SGT-149(D) substituted two hexyloxy chain units to the terminal position of each fluorene in the donor groups of porphyrin dyes. The effect of the position of the fluorene and phenylene units in the donor moiety on the photochemical and electrochemical properties, as well as the photovoltaic performance, was compared with the reference dyes of SGT-021 and SGT-149, previously reported by the research group. After optimizing the DSSC devices, SGT-021(D) and SGT-021(D0) achieved a high PCE of 11.6 and 10.5%, respectively, while SGT-149(D) exhibited a little lower PCE of 10.3% under the standard AM 1.5G light intensity. The cell performance of DSSC devices based on SGT-021(D) and SGT-149(D) was inferior to the corresponding reference dyes of SGT-021 and SGT-149 due to their lower donating ability of Hexyloxy-BPFA than Hexyloxy-BFPA.