Nitrogen Research Articles

Recent Progress in Isolating and Purifying Amide Alkaloids from their Natural Habitats: A Review

: Alkaloids are nitrogen-containing chemical compounds found in nature. Many alkaloids are heterocyclic in nature. They are nitrogen-based organic compounds with the nitrogen atoms enclosed in a heterocyclic ring. The chemical "pro alkaloid" is derived from the alkyl amines in it. Many ancient people, long before the advent of organic chemistry, recognized that many of these substances have measurable effects on the body's physiological functions. Alkaloids are a type of natural substances that are classified as secondary metabolites. Many different types of organisms create alkaloids, which are a class of natural products. Alkaloids showed antifungal, local anesthetic, anti-inflammatory, anticancer, analgesic, neuropharmacologic, antimicrobial, and many other activities. Amines, as opposed to alkaloids, are the more common classification for naturally occurring compounds that contain nitrogen in the exocyclic position (such as mescaline, serotonin, and dopamine). An amide molecule has a nitrogen atom that is chemically bound to a carbon atom in the carbonyl group. The -oic acid ending of the corresponding carboxylic acid is converted to -amide to form the correct nomenclature for an amide. This article offers an overview of numerous techniques for extracting, separating, and purifying alkaloids for use in natural medicine.

Bioavailability of dissolved organic matter (DOM) derived from seaweed Gracilaria lemaneiformis meditated by microorganisms

Seaweed Gracilaria lemaneiformis, a significant oceanic primary producer, releases substantial dissolved organic matter (DOM) during growth and decay, potentially impacting coastal organic carbon reservoirs and microbial communities. This study aimed to investigate the bioavailability of Gracilaria-derived DOM and its interactions with microbial communities. Laboratory experiments introduced Gracilaria-derived DOM into natural seawater, tracking variations in DOM composition, microbial structure, and eight extracellular enzyme activities over 168 h. The results indicated a rapid breakdown of dissolved organic carbon, nitrogen, and phosphorus, representing 48 % to 90 % of their total concentrations within 168 h, highlighting the high DOM bioavailability. Tryptophan substances were identified as the primary components of Gracilaria-derived DOM, being highly labile and utilized by microorganisms. Within the initial 0–12 h of DOM influx, Proteobacteria significantly increased and dominated in bacterial community, while after 48 h, as DOM decomposed, Desulfobacterota became the dominant group. The labile DOM stimulated bacteria, particularly Proteobacteria, to release substantial extracellular enzymes that peaked within the first 12 h. Subsequent substrate depletion led to decreased enzyme activities. Positive correlations were observed among bacterial abundance, enzyme activities, and tryptophan substances, emphasizing the intricate interplay among microbial communities, labile DOM, and extracellular enzymes. This study underscores the high bioavailability of Gracilaria-derived DOM and its interactions with microbial communities in nearshore environments.

Comprehensive analysis of water and sediment from holy water body ‘Pokhri’ reveals presence of biomolecules that may educe skin, gastroenterological and neurological dysfunction

‘Pokhri mai’ refers to the natural pond amidst the hilly forest slopes of the Buxa tiger reserve (BTR) nearby Jayanti considered to be sacred by the local ethnic groups serving as the prime source of water for wild animals and occasionally by neighbouring inhabitants. However, the water body is designated to be noxious by a group of native people with no scientific validation. This paper focuses to explore its toxicity status and allied environmental concerns through Pokhri water and sediment sample analysis through physicochemical assessment, in vitro antioxidant assay, microbiological investigation followed by AAS, GC–MS and in silico study. pH of soil and water samples were found to be quite high (>6.8) with organic matter, carbon and available nitrogen content being 1.5308 ± 0.28 %, 0.89 ± 0.17 % and 0.072 ± 0.34 % respectively. Profuse microbial growths were observed in both sediment and water samples with consortia obtained exhibiting tolerance against a range of antifungals and antibiotics. Inhibition zone was absent for sediment consortium whereas consortium of water samples portrayed susceptibility against various heavy metals viz. Cu2+, Pb2+, Zn2+, Fe3+ and Al3+ salts with corresponding AAS quantified values of sediment samples being 133, 223.3, 86.8, 1449 and 481.5 ppm. A summative of 18 metabolites were identified by GC–MS in Pokhri lake sediment among which 13 (occupying 96.35 % peak area) were investigated to be potentially toxic with 2,4-Di-tert-butylphenol (53.38 %) as the major compound. Biomolecular characterization, ADMET test and molecular docking study with dermal, gastrointestinal and neural peptides exhibiting high binding affinity scores (ranging between −2.6 to −8.3 kcal/mol) further affirmed the toxicity attributes of the GC–MS deciphered molecules. The findings clearly justifies the local ‘myth’ of Pokhri water to be deleterious with prospective dermatotoxic, neurotoxic and being evident of gastrointestinal toxicity emphasizing ecological risk to the environment, wildlife and microflora of the adjoining forests.

Excellent tensile strengthening and corrosion resistance of M50 bearing steels by plasma torch surface nitrogen atoms injection

Excellent tensile strengthening and corrosion resistance of M50 bearing steels by plasma torch surface nitrogen atoms injection

The Coordination Bond Reinforced FeOCl/C3N4 Heterostructure for Photocatalytic Degradation of Persistent Organic Pollutants

Persistent organic pollutants (POPs) present a substantial environmental challenge due to their enduring nature and adverse effects on human health. The exploration of photocatalysts featuring abundant active sites and appropriate band structures represents a promising approach for harnessing solar energy in photo-self-Fenton reactions for pollutant oxidation. In this investigation, a two-dimensional S-scheme FeOCl/C3N4 heterostructure was fabricated for the degradation of POPs. The coordination between dangling nitrogen atoms in C3N4 and Fe3+ in FeOCl established a novel pathway for the transfer of photogenerated electrons, thereby prolonging their lifespan by mitigating recombination events. Assessment of the photocatalytic performance using 4-chlorophenol (4-CP) as a model pollutant revealed a 5.4-fold and 40-fold enhancement in degradation rate over FeOCl/C3N4 compared to individual catalysts. Notably, nearly complete mineralization rates were achievable with FeOCl/C3N4, underscoring its robustness. Mechanistic investigations delineated hydroxyl radicals (•OH) as the primary active species responsible for pollutant degradation.

N,N-Disubstituted 4-Sulfamoylbenzoic Acid Derivatives as Inhibitors of Cytosolic Phospholipase A2α: Synthesis, Aqueous Solubility, and Activity in a Vesicle and a Whole Blood Assay.

Cytosolic phospholipase A2α (cPLA2α) is the key enzyme that initiates the arachidonic acid cascade through which pro-inflammatory lipid mediators can be formed. Therefore, cPLA2α is considered an interesting target for the development of anti-inflammatory drugs. Although several effective inhibitors of the enzyme have been developed, none of them has yet reached clinical application. Recently, we have prepared new 4-sulfamoylbenzoic acid derivatives based on a cPLA2α inhibitor found in a ligand-based virtual screening. The most effective of these compounds were now subjected to further variations in which the substitution pattern on the sulfamoyl nitrogen atom was changed.. The new compounds were tested in vitro in a vesicle assay for cPLA2α inhibition as well as for their water solubility, metabolic stability, and selectivity towards related enzymes. In addition, they were evaluated ex vivo in a whole blood assay in which metabolites of the arachidonic acid cascade formed after activation of cPLA2α were quantified using a combined online dilution/ online solid phase extraction HPLC-MS method. Inhibitors with submicromolar inhibitory in vitro potency were found with favourable water solubility and selectivity. However, their efficacy did not match that of the highly effective, known, structurally related cPLA2α inhibitor giripladib, which was also tested as a reference. One advantage of some of the new compounds compared to giripladib was their significantly improved water solubility. When analyzing the substances in the ex vivo whole blood assay, it was found that the obtained inhibition data correlated better with the in vivo results when the phorbol ester 12-Otetradecanoylphorbol- 13-acetate was used for activation of the enzyme in the blood cells instead of the calcium ionophore A23187. New compounds with good activity towards cPLA2α and reasonable physicochemical properties were identified. Overall, the results obtained could be helpful in the development of clinically applicable inhibitors of this enzyme.

Effect of AP and AN on the combustion and injection performance of Al-H2O gelled propellant

Aluminum-water propellants (Al-H2O propellants), representing a novel class of solid propellants, demonstrate the merits of cost efficiency and reduced feature signal characteristics. However, the conventional formulations of Al-H2O propellants are hampered by the generation of substantial condensed residues. In our investigation, we explored the incorporation of oxidizers into the Al-H2O propellant grain, aiming to enhance combustion and injection performance. Employing a multifaceted experimental approach, we conducted thermal gravimetric analysis, laser ignition experiments, and ignition tests within a lab-scale solid rocket motor (SRM) firing to systematically examine the effects of varying content of ammonium perchlorate (AP) and ammonium nitrate (AN) on the combustion and injection performance of Al-H2O propellants. Our findings indicated that integrating AP and AN at a mass fraction of 3 % each notably curtailed ignition delay time by approximately 67 % and 90 %, respectively, and concurrently decreased burning rates by approximately 50 % and 58 %. Significantly, it has been observed that a composition incorporating a 5 % mass fraction of AP enhances the combustion efficiency of the Al-H2O propellant system by approximately 2 %. Conversely, the integration of a 5 % mass fraction of AN into the same propellant matrix results in an augmentation of the injection efficiency by an estimated 47 %. Empirical evidence validating the augmentative impacts of AP and AN on the performance of Al-H2O propellants has been substantiated through a series of motor hot firing experiments. Furthermore, the combustion behavior of Al-H2O propellants has been elucidated through an analysis of the combustion physical mechanism of Al particles. The thermal decomposition of AP yields a substantial volume of oxidizing gases, which effectively accelerates the combustion rate of the Al particles, subsequently leading to an enhancement in the overall combustion efficiency of the propellant. Conversely, the decomposition of AN results in an increased production of nitrogen gas, thereby augmenting the velocity of gas flow and, consequently, elevating the injection efficiency of the propellant. This finding holds promise for guiding the developmental trajectory of Al-H2O propellants and refining the design parameters of propulsion systems.

Forms, Importance and Sources of Dissolved Organic Nitrogen (DON) in the Environment: A Review

Forms, Importance and Sources of Dissolved Organic Nitrogen (DON) in the Environment: A Review

Investigation of nitrogen conversion in ditch-treated greywater: Contributions of biochar and aeration

This study aimed to assess the contribution of different combinations of uninterrupted aeration and tidal flow modes, as well as shallow and deep biochar landfill methods, to nitrogen removal pathways in ditches. Compared to natural ditches, the addition of biochar and aeration resulted in higher water pollution removal rates, lower Greenhouse Gas (GHG) emissions, and reduced sediment leaching. The nitrogen mass balance revealed that Total Nitrogen removal efficiency of each ditch group was 25.33% for CA-C, 43.75% for DBT-C, 49.08% for UBT-C, 30.75% for DBA-C, and 45.16% for UBA-C. Compared to the control group (CA-C), the tidal flow group with deep biochar landfill (DBT-C)demonstrated the highest efficiency in total nitrogen removal. To elucidate the fate of nitrogen elements, potential transformation processes of unexplained nitrogen were explored. The primary outflow pathway of nitrogen pollution in ditches is through liquids. The nitrogen composition in the liquid of each ditch indicated that for shallow biochar configurations (UBT-C/UBA-C), denitrification might be the main factor limiting TN removal efficiency. In contrast, for deep biochar configurations (DBT-C/DBA-C), hydrolysis and nitrification of organic nitrogen were identified as limiting factors, with tidal flow alleviating these limitations. Overall, the combination of shallow biochar and tidal flow aeration in a ditch is the most effective method for removing rural greywater, providing valuable insights for the development of design parameters in greywater removal systems.

A Review on The Nitrogen Laser

Abstract: A nitrogen laser is a type of gas laser that uses molecular nitrogen as its gain medium to operate in the ultraviolet (UV) spectrum. First created in 1963, nitrogen lasers were first put to use in commerce in 1972. A nitrogen laser is a type of gas laser that uses molecular nitrogen as its gain medium to operate in the ultraviolet (UV) spectrum. First created in 1963, nitrogen lasers were first put to use in commerce in 1972.Applications for nitrogen lasers can be found in physics, chemistry, and medical research. The principle of operation for nitrogen lasers is a quick electrical discharge through nitrogen gas. Liquid nitrogen or a gas cylinder might be used to supply the nitrogen gas. The UV-wavelength laser light has a short pulse width and a high intensity. The principle of operation for nitrogen lasers is a rapid electrical discharge via nitrogen gas. Liquid nitrogen or a gas cylinder might be used to supply the nitrogen gas. The laser light has a short pulse width, high intensity, and is released into the ultraviolet spectrum. Electricity is used by the nitrogen laser to excite the nitrogen. The electrons in the laser strike the nitrogen atoms in the air when an electric spark passes through a spark gap, stimulating them into a metastable condition. A photon with a wavelength of 337 nm causes stimulated emission and the creation of a laser state in the excited nitrogen atoms. Electricity is used by the nitrogen laser to excite the nitrogen. The nitrogen atoms in the air are excited into a metastable condition when an electric spark passes through a spark gap in the laser. A photon with a wavelength of 337 nm causes stimulated emission and the creation of a laser state in the excited nitrogen atoms. [22]

Coastal Supra-Permafrost Aquifers of the Arctic and Their Significant Groundwater, Carbon, and Nitrogen Fluxes.

Fresh submarine groundwater discharge (FSGD) can deliver significant fluxes of water and solutes from land to sea. In the Arctic, which accounts for ∼34% of coastlines globally, direct observations and knowledge of FSGD are scarce. Through integration of observations and process-based models, we found that regardless of ice-bonded permafrost depth at the shore, summer SGD flow dynamics along portions of the Beaufort Sea coast of Alaska are similar to those in lower latitudes. Calculated summer FSGD fluxes in the Arctic are generally higher relative to low latitudes. The FSGD organic carbon and nitrogen fluxes are likely larger than summer riverine input. The FSGD also has very high CO2 making it a potentially significant source of inorganic carbon. Thus, the biogeochemistry of Arctic coastal waters is potentially influenced by groundwater inputs during summer. These water and solute fluxes will likely increase as coastal permafrost across the Arctic thaws.

Nitrogen substitution of bilayer penta-carbides: high solar-to-hydrogen conversion efficiency and excellent electrocatalytic activity for water splitting.

The shortage of fossil energy and environmental crises are two important issues in the 21st century, and the search for alternatives to fossil fuels, e.g. H2, is crucial. Herein, based on penta-germagraphene p-Ge2C4, bilayer penta-carbides of p-Ge4C8 and nitrogen substituted materials p-Ge4NnC8-n are proposed. The results indicate that gradually replacing the carbon atoms on the surface of p-Ge4C8 with nitrogen atoms can change the surface activities and electronic structures, and this is beneficial for both photocatalysis and electrocatalysis. The vertical intrinsic electric field in the two-dimensional materials can enhance photocatalytic water splitting of p-Ge2C4/Ge2N2C2 and break the conventional limitation of 1.23 eV for the band gap of photocatalysts. Therefore, solar energy conversion efficiency can reach 31%. The smaller effective mass and deformation potential of p-Ge2C4/Ge2N2C2 along the x and y directions lead to a huge electron mobility (425.64 × 103 cm2 V-1 s-1) at room temperature. Moreover, the overpotential for the hydrogen evolution reaction of p-Ge2C4/Ge2N2C2 is 0.074 V, which is beneficial for electrocatalysis. The external strain and electric field can also enrich the electronic properties. Surface modification achieved by introducing the nitrogen atoms can improve the catalytic performance of penta-carbides.

Synthesis and Characterization of Two Sparfloxacin Crystalline Salts: Enhancing Solubility and In Vitro Antibacterial Activity of Sparfloxacin

Background: To improve the solubility and permeability of Sparfloxacin (SPX) and enhance its antimicrobial activity in vitro, two unreported pharmaceutical crystalline salts were synthesized and characterized in this paper. One is a hydrated crystal of Sparfloxacin with Pimelic acid (PIA), another is a hydrated crystal of Sparfloxacin with Azelaic acid (AZA), namely, SPX-PIA-H2O (2C19H23F2N4O3·C7H10O4·2H2O) and SPX-AZA-H2O (4C19H23F2N4O3·2C9H14O4·5H2O). Methods: The structure and purity of two crystalline salts were analyzed using solid-state characterization methods such as single-crystal X-ray diffraction, powder X-ray diffraction, differential scanning calorimetry, thermogravimetric analysis, and infrared spectroscopy. Additionally, the interaction characteristics between two crystal salt molecules were examined by constructing Hirshfeld surfaces and mapping specific real-space functions through Hirshfeld surface analysis. The solubility under physiological conditions, diffusivity across simulated biological membranes, and in vitro antibacterial activity against specific bacterial strains of two crystalline salts were evaluated using established assays, including minimum inhibitory concentration (MIC) tests. Results: Single-crystal X-ray diffraction and Hirshfeld surface analysis indicate that SPX forms stable crystal structures with PIA through charge-assisted hydrogen bonds N1-H1e···O10 (1.721 Å, 173.24°), N5-H5a···O11 (1.861 Å, 169.38°), and with AZA through charge-assisted hydrogen bonds N5-H5B···O8 (1.810 Å, 154.55°), N4-H4B···O6 (1.806 Å, 174.97°). The binding sites of two crystalline salts were at the nitrogen atoms on the piperazine ring of SPX. Compared with SPX, the equilibrium solubility of the two crystalline salts was improved by 1.17 and 0.33 times, respectively, and the permeability of the two crystalline salts was increased by 26.6% and 121.9%, respectively. In addition, SPX-AZA-H2O has much higher antibacterial activity on Pseudomonas aeruginosa and Bacillus subtilis than SPX. Conclusions: This research yielded the successful synthesis of two crystalline salts of Sparfloxacin (SPX), significantly improving its solubility and diffusivity, and bolstering its antibacterial efficacy against targeted bacterial species. These breakthroughs set the stage for innovative advancements in the realm of antimicrobial drug development.

Tobacco production under global climate change: combined effects of heat and drought stress and coping strategies

With the intensification of global climate change, high-temperature and drought stress have emerged as critical environmental stressors affecting tobacco plants’ growth, development, and yield. This study provides a comprehensive review of tobacco’s physiological and biochemical responses to optimal temperature conditions and limited irrigation across various growth stages. It assesses the effects of these conditions on yield and quality, along with the synergistic interactions and molecular mechanisms associated with these stressors. High-temperature and drought stress induces alterations in both enzymatic and non-enzymatic antioxidant activities, lead to the accumulation of reactive oxygen species (ROS), and promote lipid peroxidation, all of which adversely impact physiological processes such as photosynthetic gas exchange, respiration, and nitrogen metabolism, ultimately resulting in reduced biomass, productivity, and quality. The interaction of these stressors activates novel plant defense mechanisms, contributing to exacerbated synergistic damage. Optimal temperature conditions enhance the activation of heat shock proteins (HSPs) and antioxidant-related genes at the molecular level. At the same time, water stress triggers the expression of genes regulated by both abscisic acid-dependent and independent signaling pathways. This review also discusses contemporary agricultural management strategies, applications of genetic engineering, and biotechnological and molecular breeding methods designed to mitigate adverse agroclimatic responses, focusing on enhancing tobacco production under heat and drought stress conditions.

Improving Molecular Arrangement and Alleviating Nonradiative Energy Loss Using a Chlorinated Pyrido[3,4‐b]Quinoxaline‐Core‐Based Acceptor for High‐Performance Organic Solar Cells

AbstractThe electron‐deficient A1 unit in A‐DA1D‐A structured acceptors is critical for optimizing the efficiency of organic solar cells (OSCs). Drawing inspiration from the high performance of the previously reported pyrido[2,3‐b]quinoxaline‐core acceptors, Py6, an isomer of Py1 is designed with a repositioned pyridine nitrogen atom, and further modified it by chlorinating Py6 to create Py7. Theoretical calculations show that chlorine incorporation strengthens intermolecular non‐covalent interactions and promotes the tighter molecular stacking, as confirmed by grazing‐incidence wide‐angle X‐ray scattering. Consequently, D18/Py7 device delivers the enhanced fill factor and short‐circuit current density, compared to D18/Py1 and D18/Py6 device. Notably, D18/Py7 device also yields a higher open‐circuit voltage of 0.871 V, significantly outperforming Py1 (0.764 V) and Py6 (0.723 V), due to the low nonradiative energy losses. Further studies reveal that introducing Cl directs hole density toward the central pyrido[3,4‐b]quinoxaline unit and decreases the charge transfer state ratio of D18/acceptor. This prompts triplet‐to‐singlet conversion and reduces non‐radiative recombination losses. Additionally, using a mutual donor–acceptor dilution strategy, the (D18:1wt.% Py7)/(Py7:1wt.% D18) device achieves an impressive efficiency of 19.60%. This work emphasizes the great potential of the Py‐series acceptors and demonstrates that chlorine incorporation effectively reduces non‐radiative losses.

Interaction of Difluorocarbene with the Thiocyanate Anion: Access to a Silicon Reagent Bearing the Isothiocyanate Group.

The reaction between (bromodifluoromethyl)trimethylsilane (TMSCF2Br) and potassium thiocyanate providing TMSCF2NCS is described. The process involves the interaction of difluorocarbene with the nitrogen atom of the thiocyanate anion. The obtained silicon reagent served as a source of the fluorinated group and difluorocarbene in the reaction with N-alkyl imines, affording 2-(difluoromethylthio)-4-fluoroimidazoles.

RESULTS REGARDING THE INFLUENCE OF GREEN MANURE USAGE ON MAIZE CROP ON ACIDIC SOILS IN THE NORTHWEST OF THE COUNTRY

This paper presents the efficacy of green manures in raising soil fertility and enhancing crop productivity, on the Albic Luvisols in northwestern Romania.Green manures are cover crops that provide various benefits when added to the soil. Peas are especially effective at increasing organic nitrogen in the soil, leaving behind a significant amount of 471.74 kg N(a.s.) per hectare. Regardless of the pressure from the pathogen Fusarium spp. and the pest Ostrinia n. the maize yield was not affected. The incorporated green manures especially peas, significantly raises maize yield surpassing the control with almost 3000 kg. The quality of the maize crop, specifically starch content and hectoliter weight, was not influenced by either green manure or chemical fertilization.

Synthesis, Crystal Structures, Antimicrobial Activity, and Acute Toxicity Evaluation of Chiral Zn(II) Schiff Base Complexes

Four mononuclear bioefficient zinc coordination complexes [Zn(NN)3](ClO4)2 (A–D) involving chiral bidentate Schiff base ligands have been synthesized and characterized by IR, 1H, and 13C NMR spectroscopy and mass spectrometry. X-ray crystal structures of three of the zinc complexes revealed that the zinc metal ion is hexacoordinated, exhibiting a distorted octahedral geometry where both the nitrogen atoms (NN = pyridyl and imine) of imines are coordinated to the central zinc ion. The isolated zinc complexes were evaluated for their antimicrobial activity in vitro against Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus, displaying varying levels of growth inhibition. An acute toxicity test conducted using Artemia salina and Swiss albino mice showed that the zinc complexes A–D were non-toxic towards A. salina at concentrations below 414, 564, 350, and 385 µM, respectively, and did not affect liver biochemical parameters, although pyknosis was induced in hepatocytes of the treated mice.

Skeletal Nitrogen Functionalization of Isostructural 2D Conjugated MOFs for Enhancement of the Dual-Ion Storage Capacity.

Two-dimensional conjugated metal-organic frameworks (2D c-MOFs) are emerging as promising electrode materials for electrochemical energy storage. However, a viable path to realize superior dual-ion storage in 2D c-MOFs has remained elusive. Here, we report the synthesis of Cu2(Nx-OHPTP) 2D c-MOFs (x=0,1,2; OHPTP=octahydroxyphenanthrotriphenylene) with precise aromatic carbon-nitrogen arrangements, based on the π-conjugated OHPTP ligand incorporated with one or two nitrogen atoms. The skeletal nitrogen modification in Cu2(Nx-OHPTP) allows the synergistic introduction of additional redox sites, and thus substantially favors the unique dual-ion adsorption capacity. Consequently, the Cu2(N2-OHPTP) cathode exhibits a largely enhanced electrochemical performance for dual-ion storage (i.e., Li+ and Cl-) with a high specific capacity of 53.8 mAh g-1, which is twice that of Cu2(N0-OHPTP) and 1.3 times that of Cu2(N1-OHPTP). Furthermore, the Cu2(N2-OHPTP) electrode displays a favorable rate performance of 52% and good cycling stability of 96% after 1000 cycles. We identify N-centered redox sites as additional Li+ adsorption sites. In addition, calculations underline the synergistic enhancement of the Cl- adsorption energy by about 1.0 eV at the more electron-poor CuO4 linkages after N-incorporation. This work paves the way for the precise design of 2D c-MOFs with superior electrochemical properties, advancing their application in dual-ion storage applications.

Skeletal Nitrogen Functionalization of Isostructural 2D Conjugated MOFs for Enhancement of the Dual‐Ion Storage Capacity

Two‐dimensional conjugated metal‐organic frameworks (2D c‐MOFs) are emerging as promising electrode materials for electrochemical energy storage. However, a viable path to realize superior dual‐ion storage in 2D c‐MOFs has remained elusive. Here, we report the synthesis of Cu2(Nx‐OHPTP) 2D c‐MOFs (x=0,1,2; OHPTP=octahydroxyphenanthrotriphenylene) with precise aromatic carbon‐nitrogen arrangements, based on the π‐conjugated OHPTP ligand incorporated with one or two nitrogen atoms. The skeletal nitrogen modification in Cu2(Nx‐OHPTP) allows the synergistic introduction of additional redox sites, and thus substantially favors the unique dual‐ion adsorption capacity. Consequently, the Cu2(N2‐OHPTP) cathode exhibits a largely enhanced electrochemical performance for dual‐ion storage (i.e., Li+ and Cl‐) with a high specific capacity of 53.8 mAh g−1, which is twice that of Cu2(N0‐OHPTP) and 1.3 times that of Cu2(N1‐OHPTP). Furthermore, the Cu2(N2‐OHPTP) electrode displays a favorable rate performance of 52% and good cycling stability of 96% after 1000 cycles. We identify N‐centered redox sites as additional Li+ adsorption sites. In addition, calculations underline the synergistic enhancement of the Cl− adsorption energy by about 1.0 eV at the more electron‐poor CuO4 linkages after N‐incorporation. This work paves the way for the precise design of 2D c‐MOFs with superior electrochemical properties, advancing their application in dual‐ion storage applications.