Electron Donor Research Articles

Synergistic removal of bio-recalcitrant organic compounds and nitrate: Coupling photocatalysis and biodegradation to enhance the bioavailability of electron donors

Nitrate pollution poses significant threats to both aquatic ecosystems and human well-being, particularly due to eutrophication and increased risks of methemoglobinemia. Conventional treatment for nitrate-contaminated wastewater face challenges stemming from limited availability of carbon sources and the adverse impacts of toxins on denitrification processes. This study introduces an innovative Intimately Coupled Photocatalysis and Biodegradation (ICPB) system, which utilizes Ag3PO4/Bi4Ti3O12, denitrifying sludge, and polyurethane sponge within an anoxic environment. This system demonstrates remarkable efficacy in simultaneously removing bio-recalcitrant organic compounds (such as sulfamethoxazole) and nitrates, surpassing standalone treatment methods. Optimally, the ICPB achieves complete removal of sulfamethoxazole, along with 87.7 % removal of DOC, and 81.8 % reduction in nitrate levels. Its ability to sustain pollutant removal and biological activity over multiple cycles can be attributed to the special formation of biofilm and mineralization of sulfamethoxazole, minimizing both photocatalytic damage and toxic inhibitory effects on microbes. The dominant microbial genera of ICPB system included Castellaniella, Acidovorax, Raoultella, Giesbergeria, and Alicycliphilus. Additionally, the study sheds light on a potential mechanism for the concurrent treatment of recalcitrant organics and nitrates by the ICPB system, presenting a novel and highly effective approach for addressing biologically resistant wastewater.

Ascorbic acid-mediated enhancement of antioxidants and photosynthetic efficiency: A strategy for enhancing canola yield under salt stress

Ascorbic acid (AsA), a water-soluble antioxidant, act as cofactor for enzymes that regulate photosynthesis, hormonal and antioxidant biosynthesis that enables the plants to alleviate the harmful effects of salinity stress. The study was aimed to investigate the ameliorative role of foliar application of 200 ppm ascorbic acid (AsA) in improving growth by changing antioxidant response, photosynthetic capacity and mineral nutrient status of two canola varieties (Dunkled and Cyclone) under salinity stress (200 mM NaCl). Salt stress reduced plant biomass, photosynthetic activity, and accumulation of macro and micronutrients such as K+, Ca2+and Zn2+ in both canola varieties, on the other hand accumulation of Na+ and Cl−was increased. The salinity-induced oxidative stress (H2O2 and MDA) caused photoinhibition of PSII at the donor and acceptor ends. The salinity-induced reduction in efficiency of electron donation to PSII (Fv/Fo) and electron transport through PSII (Fm/Fo), especially in Cyclone, significantly reduced ETRII thus enhancing CEF around PSI and NPQ in both canola varieties that has been considered as photo-protective mechanism of plants. In addition, salt stress enhanced CEF around PSI. However, application of AsA improved the structural stability of PSII, linear electron transport and reduced donor end limitation of PSI activity by improving electron transfer from PSII to PSI. The application of AsA improved the stomatal conductance, inter-cellular CO2 concentration and net CO2 assimilation rate thereby resulting in improved consumption of extra-electrons in CO2 fixation generated by photosynthetic electron transport. Exogenous AsA application reduced the oxidative stress and improved the antioxidant potential by managing extra-electrons produced in CO2 fixation. All these physiological and biochemical changes due to AsA application helped the canola plants to improve growth and yield under salinity. Thus, the application of ascorbic acid has the potential to ameliorate the detrimental effects of NaCl stress on canola plants.

Enhanced Li bonds enable bidirectional sulfur catalysis by a molecular Co-N4 catalyst for lithium-sulfur batteries

Sulfur conversion catalysis is an effective strategy to tackle the inherent polysulfide shutting and fast capacity decay in lithium-sulfur batteries. Previous studies identified cobalt phthalocyanine as a unique molecular catalyst with Co-N4 active sites to promote sulfur reduction reactions. Herein, enhancing the Li bonds with the pyridinic N atoms on the phthalocyanine ligand is demonstrated to endow further catalytic activity in sulfur oxidation reactions. This is enabled by peripheral substitution with electron-donating methoxy groups that strengthens the electronegativity of the pyridinic N atoms. DFT calculations and metadynamics simulations identify the key role of Li bonds in reducing the energy barrier of Li2S dissociation. The highly lithiophilic methoxy groups also stabilize the dissociated Li cations in their solvation structure. The dissociated S anion can then be oxidized to higher-order polysulfides or radicals by electron donation to the Co-N4 center, which activates Li2S for subsequent oxidation. Meanwhile, the catalytic activity in sulfur reduction reactions is also improved by a more efficient electron transfer to adsorbed Li2S4, during which the strengthened Li bonds are beneficial in mediating the breakage of the bridging S-S bond. Significant performance improvements are achieved with the bidirectional catalyst under high areal sulfur loading and in Li-S pouch cells.

Phosphonium Iodide Featuring Blue Thermally Activated Delayed Fluorescence for Highly Efficient X‐Ray Scintillator

AbstractOrganic scintillators are praised for their abundant element reserves, facile preparation procedures, and rich structures. However, the weak X‐ray attenuation ability and low exciton utilization efficiency result in unsatisfactory scintillation performance. Herein, a new family of highly efficient organic phosphonium halide salts with thermally activated delayed fluorescence (TADF) are designed by innovatively adopting quaternary phosphonium as the electron acceptor, while dimethylamine group and halide anions (I−) serve as the electron donor. The prepared butyl(2‐[2‐(dimethylamino)phenyl]phenyl)diphenylphosphonium iodide (C4‐I) exhibits bright blue emission and an ultra‐high photoluminescence quantum yield (PLQY) of 100 %. Efficient charge transfer is realized through the unique n‐π and anion‐π stacking in solid‐state C4‐I. Photophysical studies of C4‐I suggest that the incorporation of I accounts for high intersystem crossing rate (kISC) and reverse intersystem crossing rate (kRISC), suppressing the intrinsic prompt fluorescence and enabling near‐pure TADF emission at room temperature. Benefitting from the large Stokes shift, high PLQY, efficient exciton utilization, and remarkable X‐ray attenuation ability endowed by I, C4‐I delivers an outstanding light yield of 80721 photons/MeV and a low limit of detection (LoD) of 22.79 nGy ⋅ s−1. This work would provide a rational design concept and open up an appealing road for developing efficient organic scintillators with tunable emission, strong X‐ray attenuation ability, and excellent scintillator performance.

GFP Chromophore Integrated Conjugated Microporous Polymers toward Bioinspired Photocatalytic CO2 Reduction to CO.

The development of highly active, durable, and low-cost metal-free catalysts for the photocatalytic CO2 reduction reaction (CO2RR) is an efficient and environmentally friendly solution to address significant problems like global warming and high energy demand. In the present study, we have demonstrated the design and synthesis of a donor-acceptor based conjugated microporous polymer (CMP), TPA-GFP, by integrating an electron donor, tris(4-ethynylphenyl)amine (TPA), with a green fluorescent protein chromophore analogue (Z)-4-(2-hydroxy-3,5-diiodobenzylidene)-1-(4-iodophenyl)-2-methyl-1H-imidazol-5(4H)-one (o-HBDI-I3) (GFP). In comparison to nondonor 1,3,5-triethynylbenzene (TEB) based TEB-GFP CMP, photocatalytic CO2 reduction using donor-acceptor based TPA-GFP CMP displays a 3-fold increment of CO production yield with a maximum CO yield of 1666 μmol g-1 at 12 h. Further, the CO selectivity increases significantly from a mere 54% in TEB-GFP to an impressive 95% in TPA-GFP. The impressive CO2 reduction efficiency and selectivity for TPA-GFP can be attributed to the efficient light-harvesting capability and facile charge separation and migration through donor-acceptor building units of the CMP. The mechanistic aspect of the photocatalytic CO2 reduction process is explored using in situ DRIFTS and DFT calculation, and a plausible photocatalytic mechanism is proposed.

Mixed ligand complexes of Pt(II) Tertiary phosphines and 1-(benzo[d]thiazol-2-yl)-3-phenylthiourea; Crystal structure and DFT of [Pt(C14H9N3S2)(dppe)].CH2Cl2

This paper describes a series of Pt(II) thiourea complexes (1–4). The complexes were synthesized by a reaction between [PtCl2(diphos)] and the ligand 1-(benzo[d]thiazol-2-yl)-3-phenylthioure in the presence of triethylamine, with all reactants present in equimolar amounts. The produced complexes exhibited square planar geometry, which was validated by FT-IR and 1HNMR . Single crystal XRD study revealed that the coordination geometry was distorted square planar in [Pt(Btzt)(dpppe)]. Hirshfeld surface analysis was used to delve deeper into the intermolecular interactions which showed that the combined contribution of H⋯H and H⋯C contacts in the stabilization of the supramolecular assembly was 81.3%. A void analysis was carried out which showed that there was no large cavity in the supramolecular assembly. Theoretical studies were also conducted on [Pt(Btzt)(dpppe)]. The DFT analysis was carried out using the B3LYP Hybrid method in combination with Def2-SVP. The theoretical findings indicated just 3% differences between the theoretical and experimental Figures. Furthermore, the computed HOMO-LUMO gap was 3.4 eV, which was close to the anatase photocatalyst's band gap. DFT predicted that all complexes are non-magnetic with μB=0. There are high electron donation and back-donation between heteroatoms and transition metals in the complexes.

Adsorption behavior of Cl2 on TiC0.89O0.11(001) surface based on the first principle calculation

Based on the first-principles ab initio calculation method of density functional theory (DFT), the adsorption models of Cl2 molecules on both the TiC0.89O0.11(001) intact surface and the carbon vacancy surface were established, followed by calculations and analysis of the adsorption structures, adsorption energy, differential charge density, and density of states (DOS). The results demonstrate that the adsorption process of Cl2 molecules on the TiC0.89O0.11(001) surface involves chemical adsorption, with a higher likelihood of dissociation into Cl atoms during adsorption. These dissociated Cl atoms can potentially interact with surface Ti and/or C atoms to form Ti-Cl bonds, C-Cl bonds, Ti-Cl-C bonds, and Ti-Cl-Ti bonds. Simultaneously, the stability of the adsorbed structure is influenced by both the bonding conditions between Cl atoms and surface atoms and the position of Cl atom adsorption (e.g., whether it is located above the vacancy C). Following adsorption, there is a weakening in the bonding strength of Ti-C or Ti-O bonds on the TiC0.89O0.11(001) surface. During the adsorption process, Cl atoms can either act as electron donors or acceptors. When the Ti-Cl bond structure is formed, Cl atoms function as electron acceptors; however, when the C-Cl bond structure is established, Cl atoms predominantly act as electron donors. Surface Ti atoms act as electron donors while surface C and O atoms function as electron acceptors. Additionally, the presence of surface carbon vacancy enhances the interaction between Cl and Ti atoms, weakens the interaction between Cl and C atoms, and attenuates the interaction between C, O, and Ti atoms in the structure. And it can augment the electron acquisition by Cl2 molecules upon adsorption, reduce the adsorption energy, and promote greater stability in the adsorption structure. All the effects contribute to facilitating TiCl4 formation.

CO-driven electron and carbon flux fuels synergistic microbial reductive dechlorination

BackgroundCarbon monoxide (CO), hypothetically linked to prebiotic biosynthesis and possibly the origin of the life, emerges as a substantive growth substrate for numerous microorganisms. In anoxic environments, the coupling of CO oxidation with hydrogen (H2) production is an essential source of electrons, which can subsequently be utilized by hydrogenotrophic bacteria (e.g., organohalide-respring bacteria). While Dehalococcoides strains assume pivotal roles in the natural turnover of halogenated organics and the bioremediation of chlorinated ethenes, relying on external H2 as their electron donor and acetate as their carbon source, the synergistic dynamics within the anaerobic microbiome have received comparatively less scrutiny. This study delves into the intriguing prospect of CO serving as both the exclusive carbon source and electron donor, thereby supporting the reductive dechlorination of trichloroethene (TCE).ResultsThe metabolic pathway involved anaerobic CO oxidation, specifically the Wood-Ljungdahl pathway, which produced H2 and acetate as primary metabolic products. In an intricate microbial interplay, these H2 and acetate were subsequently utilized by Dehalococcoides, facilitating the dechlorination of TCE. Notably, Acetobacterium emerged as one of the pivotal collaborators for Dehalococcoides, furnishing not only a crucial carbon source essential for its growth and proliferation but also providing a defense against CO inhibition.ConclusionsThis research expands our understanding of CO’s versatility as a microbial energy and carbon source and unveils the intricate syntrophic dynamics underlying reductive dechlorination.Graphical 3ez2V3iuLHAKAp3AxS5o4qVideo

An affordable, field-deployable detecting system for cyanide ion – Investigating applications in real time uses

A highly efficient system that incorporates the instantaneous visualization of the cyanide ion in water was synthesized by keeping the fluorophore system (electron donor) as a julolidine-coumarin conjugate and changing the electron acceptor unit. The probes exhibit a notable color change in normal and UV light. The probe interaction modalities are based on the ICT process. With a detection limit in the nM range, it may preferentially react with cyanide, which is less than the tolerable level of 1.9 μM. According to 1H NMR data, the probes detect cyanide ions by nucleophilic addition reaction mechanism. Furthermore, current probe successfully determines real resources, including cyanide containing cassava powder, sprouted potatoes and various water samples. Besides the test strips, an electronic Arduino device was also employed to detect the cyanide ion. As such, the developed probes exhibit outstanding practical application with respect to the cyanide ion.

Microbial assemblages and associated biogeochemical processes in Lake Bonney, a permanently ice-covered lake in the McMurdo Dry Valleys, Antarctica

BackgroundLake Bonney, which is divided into a west lobe (WLB) and an east lobe (ELB), is a perennially ice-covered lake located in the McMurdo Dry Valleys of Antarctica. Despite previous reports on the microbial community dynamics of ice-covered lakes in this region, there is a paucity of information on the relationship between microbial genomic diversity and associated nutrient cycling. Here, we applied gene- and genome-centric approaches to investigate the microbial ecology and reconstruct microbial metabolic potential along the depth gradient in Lake Bonney.ResultsLake Bonney is strongly chemically stratified with three distinct redox zones, yielding different microbial niches. Our genome enabled approach revealed that in the sunlit and relatively freshwater epilimnion, oxygenic photosynthetic production by the cyanobacterium Pseudanabaena and a diversity of protists and microalgae may provide new organic carbon to the environment. CO-oxidizing bacteria, such as Acidimicrobiales, Nanopelagicales, and Burkholderiaceae were also prominent in the epilimnion and their ability to oxidize carbon monoxide to carbon dioxide may serve as a supplementary energy conservation strategy. In the more saline metalimnion of ELB, an accumulation of inorganic nitrogen and phosphorus supports photosynthesis despite relatively low light levels. Conversely, in WLB the release of organic rich subglacial discharge from Taylor Glacier into WLB would be implicated in the possible high abundance of heterotrophs supported by increased potential for glycolysis, beta-oxidation, and glycoside hydrolase and may contribute to the growth of iron reducers in the dark and extremely saline hypolimnion of WLB. The suboxic and subzero temperature zones beneath the metalimnia in both lobes supported microorganisms capable of utilizing reduced nitrogens and sulfurs as electron donors. Heterotrophs, including nitrate reducing sulfur oxidizing bacteria, such as Acidimicrobiales (MAG72) and Salinisphaeraceae (MAG109), and denitrifying bacteria, such as Gracilimonas (MAG7), Acidimicrobiales (MAG72) and Salinisphaeraceae (MAG109), dominated the hypolimnion of WLB, whereas the environmental harshness of the hypolimnion of ELB was supported by the relatively low in metabolic potential, as well as the abundance of halophile Halomonas and endospore-forming Virgibacillus.ConclusionsThe vertical distribution of microbially driven C, N and S cycling genes/pathways in Lake Bonney reveals the importance of geochemical gradients to microbial diversity and biogeochemical cycles with the vertical water column.

Novel D–π–A dye as a co-sensitizer of indoline and benzothiadiazole dyes to enhance photovoltaic performance of dye-sensitized solar cells

A novel D–π–A type of dye (BIM33) comprising diphenylamine as electron donor, diphenylacridine as a π-bridge and cyanoacrylic acid as an anchoring unit has been synthesized and used as sensitizer and co-sensitizer in dye-sensitized solar cells (DSSCs). The DSSC based on BIM33 achieved a power conversion efficiency (PCE) of 3.19 % under one sun (AM 1.5G). To improve the photovoltaic performance of the DSSCs, this orange dye was also co-sensitized with red benzothiadiazole (C1) and purple indoline (D205) organic dyes. The DSSCs based on co-sensitizers BIM33/D205 and BIM33/C1 showed superior PCEs of 6.57 % (JSC = 13.69 mA cm−2, VOC = 0.766 V, and FF = 0.63) and 6.82 % (JSC = 14.47 mA cm−2, VOC = 0.722 V, and FF = 0.65), respectively, exhibiting significant improvements of 28 % and 36 % compared to the DSSCs based on D205 and C1, respectively. The high photovoltaic performance of the co-sensitized DSSCs may be explained by the broader visible light absorption and a denser packing of the dyes on the TiO2 surface.

Sustainable Biomass Acts as an Electron Donor for Cr(VI) Reduction during the Subcritical Hydrothermal Process: Molecular Insights into the Role of Hydrochar and Liquid Compounds.

Heavy metal pollution is a critical environmental issue that has garnered significant attention from the international community. Subcritical hydrothermal liquefaction (HTL) as an emerging green technology has demonstrated remarkable promise in environmental remediation. However, there is limited research on the remediation of highly toxic Cr(VI) using HTL. This study reveals that the HTL reaction of biomass enables the simultaneous reduction and precipitation of Cr(VI). At 280 °C, the reduction of Cr(VI) was nearly complete, with a high reduction rate of 98.9%. The reduced Cr as Cr(OH)3 and Cr2O3 was primarily enriched in hydrochar, accounting for over 99.9% of the total amount. This effective enrichment resulted in the removal of Cr(VI) from the aqueous phase while simultaneously yielding clean liquid compounds like organic acids and furfural. Furthermore, the elevated temperature facilitated the formation of Cr(III) and enhanced its accumulation within hydrochar. Notably, the resulting hydrochar and small oxygenated compounds, especially aldehyde, served as electron donors for Cr(VI) reduction. Additionally, the dissolved Cr facilitated the depolymerization and deoxygenation processes of macromolecular compounds with lignin-like structures, leading to more small oxygenated compounds and subsequently influencing Cr(VI) reduction. These findings have substantial implications for green and sustainable development.

Stability assessment of PTB7‐Th and a quinoxaline‐based polymer in both organic thin film transistors and in organic photovoltaic devices

AbstractHerein, we perform a stability assessment of two conjugated polymers that are conventionally used as electron donor polymers in the active layer of organic photovoltaic (OPV). More specifically, the impact of thermal annealing, a post‐treatment commonly applied in the OPV community, is evaluated in terms of device performance and stability. The two polymers are PTB7‐Th and QX1, and they are respectively blended with a non‐fullerene electron acceptor, herein a derivative of N‐annulated perylene diimide, that is, tPDI2N‐EH. These blends are targeted for their relatively high power conversion efficiency in outdoor conditions, but also for their potential as efficient active layer in low‐intensity (indoor) conditions—while these blends have been reported, no study on the impact of thermal annealing on their stability has been performed yet. The performance stability of these devices, tracked via the open circuit voltage, the short‐circuit current, the fill factor, and the power conversion efficiency metrics, were evaluated each day for 2 weeks and correlated to an evaluation of the microstructure of the active layer, evaluated using atomic force microscopy and UV–visible absorbance spectroscopy. Finally, transistors were prepared using only the two electron donor polymers, PTB7‐Th and QX1, to assess if some correlations could be made between the behaviour of the OPV devices and that of the electronic charge mobilities. Results contribute to identify which molecular structures and which post‐treatments are ideal to promote the stability of the active layers in the context of OPV devices.

Mechanical-energy-driven HCHO purification with lattice distortion engineering and surface grafting

Formaldehyde (HCHO) is a typical indoor air pollutant with high toxicity and wide distribution. It is of great significance to use clean energy for efficient catalytic oxidation of HCHO. In this work, Fe-doped bismuth titanate (Bi4Ti3O12) nanosheets with polyethyleneimine (PEI) grafting were prepared, exhibiting a remarkable complete elimination of HCHO under ultrasonic vibration. Piezocatalytic mechanism analysis revealed that Fe3+ doping induced lattice distortion and accelerated the transfer of electrons through valence change. Additionally, the abundant amino groups in PEI efficiently gathered formaldehyde molecules on the surface of the catalysts for next catalytic reaction as well as accelerate the separation of carriers by trapping holes as strong electron donors. It showed an effective strategy for degrading organic pollutants in the air with adsorption-enhanced piezocatalysts driven by mechanical energy.

Uncovering quantum characteristics of incipient evolutions at the photosynthetic oxygen evolving complex

Water oxidation of photosynthesis at the oxygen evolving complex (OEC) is driven by the polarization field induced by the photoelectric hole. By highlighting the role of the polarization field in reshaping the spin and orbit potentials, we reveal in this work the characteristics and underlying mechanism in the relatively simpler OEC evolutions within the states S0–S2 prior to the water oxidation. The characteristic shifts of the density of states (DOS) of the electron donor Mn atom are observed in the vicinity of the Fermi surface to occur with the spin flips of Mn atoms and the change in the Mn oxidation states during the electron transfer. Notably, the spin flips of Mn atoms point to the resulting spin configuration of the next states. It is found that the electron transfer tends to stabilize the catalyst OEC itself, whereas the proton transfer pushes the evolution forward by preparing a new electron donor, demonstrating the proton-coupled electron transfer. Meanwhile, it shows that the Mn–O bonds around the candidate Mn atom of the electron donor undergo characteristic changes in the bond lengths during the electron transfer. These concomitant phenomena uncovered in first-principle calculations characterize the essential equilibrium of the OEC between the state evolution and stability that forms the groundwork of the dynamic OEC cycles. In particular, the characteristic undulation of the DOS around the Fermi level occurring at the proton-coupled electron transfer can be used to reveal crucial processes in a wide range of realistic systems.

In situ XPS confirms enhanced hydrogen evolution in S-scheme heterojunction Cd0.8Mn0.2S/Cu2WS4 via charge vectorial separation

Solar-driven water splitting for hydrogen production is a vital approach to mitigating the energy crisis and achieving carbon neutrality and peak carbon emissions. Cd0.8Mn0.2S holds significant potential for photocatalytic hydrogen evolution but faces severe challenges due to photogenerated carrier recombination. To address this, we employed ultrasonic self-assembly to tightly couple Cu2WS4 nanosheets with Cd0.8Mn0.2S nanoparticles, forming an S-scheme heterojunction to reduce carrier recombination rates. In this configuration, Cd0.8Mn0.2S acts as the electron acceptor, and Cu2WS4 serves as the electron donor. The Cd0.8Mn0.2S/Cu2WS4 structure creates a closely spaced interface, providing the shortest transfer distance for electron migration. The S-scheme heterojunction strategy effectively suppresses the recombination of photogenerated carriers, promoting vectorial separation. Under 10 W white light irradiation, the Cd0.8Mn0.2S/Cu2WS4 composite photocatalyst exhibited remarkable hydrogen evolution activity, with a hydrogen production rate of 39.83 mmol g−1 h−1. This S-scheme heterojunction strategy lays the foundation for the structural design and large-scale application of high-activity visible-light photocatalysts.

Visible‐Light‐Promoted Cascade Radical Cyclization for Difluorochroman‐4‐ones via Electron Donor‐Acceptor Complexes

The research of electron donor‐acceptor complex has developed fast in the field of photochemistry. Herein, the green and efficient metal‐free visible‐light‐promoted synthesis of difluorochroman‐4‐ones has been achieved with 2‐(allyloxy)arylaldehyde and bromodifluoroacetamide, which is driven by noncovalent interactions between 2‐(allyloxy)arylaldehyde/N,N,N',N'‐tetramethylethylene diamine (TMEDA) and bromodifluoroacetamide/TMEDA. By precisely optimizing the electron donor and reaction solvent, a wide range of structurally diverse difluorochroman‐4‐ones, including aryl amide, aliphatic amide and ester groups, were obtained in up to 76% yields. This strategy offers the benefits of simple operation, good yields, high atomic economy and broad applicability, providing an essential complement to traditional approaches for the preparation of chroman‐4‐one skeletons without any transition metals, photocatalysts or oxidants.

Remotely Modulating the Optical Properties of Organic Charge-Transfer Crystallites via Molecular Packing.

Organic charge-transfer complex (CTC) formation has emerged as an effective molecular engineering strategy for achieving the desired optical properties via intermolecular interactions. By synthesizing organic CTCs with carbazole-based electron donors and a 7,7,8,8-tetracyanoquinodimethane acceptor and adopting a molecular linker located remotely from the charge-transfer interface within the donors, we were able to modulate near-infrared absorptive and short-wavelength infrared emissive properties. Structural characterizations performed by using single-crystal X-ray diffraction confirmed that the unique molecular arrangements induced by the steric hindrance from the remotely located linker significantly influence the electronic interactions between the donor and acceptor molecules, resulting in different photophysical properties. Our findings offer an improved understanding of the interplay between molecular packing and optoelectronic properties, providing a foundation for designing advanced materials for optoelectronic applications.

Preparation of Functionalized Ethylene-Vinyl-Alcohol Nanofibrous Membrane Filter for Rapid and Cyclic Removing of Organic Dye from Aqueous Solution.

A functionalized ethylene-vinyl-alcohol (EVOH) nanofibrous membrane (NFM) was fabricated via co-electrospinning H4SiW12O40 (SiW12) and EVOH first, and then grafting citric acid (CCA) on the electrospun SiW12@EVOH NFM. Characterization with FT-IR, EDX, and XPS confirmed that CCA was introduced to the surface of SiW12@EVOH NFM and the Keggin structure of SiW12 was maintained well in the composite fibers. Due to a number of carboxyl groups introduced by CCA, the as-prepared SiW12@EVOH-CCA NFM can form a high number of hydrogen bonds with CR, and thus can be used to selectively absorb congo red (CR) in aqueous solutions. More importantly, the CR enriched in the NFM can be rapidly degraded via photocatalysis. SiW12 in the NFM acted as a photocatalyst, and the hydroxyl groups in the NFM acted as an electron donor to accelerate the photodegradation rate of CR. Meanwhile, the SiW12@EVOH-CCA NFM was regenerated and then exhibited a relatively stable adsorption capacity in five cycles of filtration-regeneration. The bifunctional nanofibrous membrane filter showed potential for use in the thorough purification of dye wastewater.

Visible-Light-Induced Domino Perfluoroalkylation/Cyclization to Access Perfluoroalkylated Quinazolinones by an EDA Complex.

The electron donor-acceptor (EDA) complexes have been extensively studied, which formed an electronically excited state, obviating the need for an exogenous photocatalyst. Herein, we report a mild and efficient strategy for photoinduced radical domino perfluoroalkylation/cyclization using N,N,N',N'-tetramethylethane-1,2-diamine (TMEDA) as an electron donor. This protocol could be well expanded to access various polycyclic quinazolinones containing perfluoroalkyl groups, exhibiting photocatalyst-free, good functional group tolerance, and environmentally friendly features.