N-methyl-2-pyrrolidone Research Articles

Preparation and evaluation of injectable sustained-release Alendronate-loaded lipid liquid crystal on ovariectomy-induced osteoporosis in rats

Alendronate, a bisphosphonate compound, is used to treat osteoporosis by inhibiting bone resorption. However, oral consumption of Alendronate can cause severe gastrointestinal side effects, such as heartburn, difficulty swallowing, constipation or diarrhea, flatulence, and esophageal irritation or pain. To overcome this problem, an injectable sustained-release formulation of alendronate based on lipid liquid crystal (LLC) using phosphatidylcholine (PC), sorbitan monooleate (SMO), glycerol di-oleate (GDO), and N-methyl-2-pyrrolidone (NMP) or ethanol solvents was recommended. This compound was added as a base to one side of a coupling syringe, while alendronate powder was added to the other. After combining the two syringes, the resulting formulations were transferred into tubes containing PBS for in-vitro evaluation. In formulations containing ethanol, the cumulative percentage of drug release, water content, and degradation were higher than in those with NMP. Furthermore, LLC gel formulations with ethanol solvent had lower viscosity and a cubic structure, whereas LLC containing NMP had a hexagonal structure, indicating slower and longer release of alendronate in LLC-NMP formulations. In-vivo evaluations of subcutaneous injections of alendronate based on LLC formulation in rats with ovariectomy-induced osteoporosis showed significant advancements in osteogenesis markers, including RUNX2, OPG, VEGF, and Type 1 Collagen, according to Western blot analysis. These finding highlight alendronate's potential not only as a bone resorption inhibitor but also as a bone formation stimulator. Additionally, histopathology results revealed no osteoclast activity or osteoarthritis reactions in the LLC formulation group. Hence, an injectable LLC formulation containing PC, SMO and NMP could be a suitable option for developing a sustained-release LLC formulation of alendronate for osteoporosis treatment.

Solvent Dictated Organic Transformations.

Solvent plays an important role in many chemical reactions. The C-H activation has been one of the most powerful tools in organic synthesis. These reactions are often assisted by solvents which not only provide a medium for the chemical reactions but also facilitate reaching to the product stage. The solvent helps the reaction profile both chemically and energetically to reach the targeted product. Organic transformations via C-H activation from the solvent assistance perspective has been discussed in this review. Various solvents such as tetrahydrofuran (THF), MeCN, dichloromethane (DCM), dimethoxyethane (DME), 1,2-dichloroethane (1,2-DCE), dimethylformamide (DMF), dimethylsulfoxide (DMSO), isopropyl nitrile (iPrCN), 1,4-dioxane, AcOH, trifluoroacetic acid (TFA), Ac2O, PhCF3, chloroform (CHCl3), H2O, N-methylpyrrolidone (NMP), acetone, methyl tert-butyl ether (MTBE), toluene, p-xylene, alcohols, MeOH, 1,1,1-trifluoroethanol (TFE), 1,1,1,3,3,3-hexafluoroisopropanol (HFIP), tert-amyl alcohol and their roles are discussed. The exclusive role of the solvent in various transformations has been deliberated by highlighting the substrate scope, along with the proposed mechanisms. For easy classification, the review has been divided into three parts: (i) solvent-switched divergent C-H activation; (ii) C-H bond activation with solvent as the coupling reagent, and (iii) C-H activation with solvent caging and solvent-assisted electron donor acceptor (EDA) complex formation and autocatalysis.

Optimal Dispersion of Antimony-Doped Tin Oxide (ATO NPs) in Different NMP Solvent Ratios for Maximizing Photovoltaic Efficiency of Carbon-Based Perovskite Solar Cells

This study addresses interface defects in tin oxide (SnO₂) electron transport layers (ETLs) for perovskite solar cells (PSCs) by doping SnO₂ with antimony (12.9% Sb/Sn). Using a diffusion-precipitation method with varying ratios of N-Methyl-2-Pyrrolidone (NMP) and distilled water (DW) as solvents, antimony-doped tin oxide (ATO) nanoparticle layers were formed and deposited on FTO substrates. Structural and compositional analyses (XPS, EDX, and XRD) confirmed successful Sb incorporation, maintaining the SnO₂ lattice with reduced particle size. Higher NMP ratios improved conductivity to 12 S/cm, enhanced charge transport, and raised the bandgap from 3.67 eV to 3.84 eV. Optimal 100% NMP conditions yielded ATO-based ETLs achieving a power conversion efficiency (PCE) of 23.645%, with a fill factor (FF) of 43.681%, open-circuit voltage (VOC) of 1.202 V, and short-circuit current density (JSC) of 23.87 mA/cm2, underscoring the potential of ATO layers for high-performance PSCs.

Alternatives assessment of polyvinylidene fluoride-compatible solvents for N-methyl pyrrolidone substitution in lithium-ion battery cathodes

Lithium-ion batteries (LIBs) are central to electrification yet, to increase the efficiency and scalability of electric systems, energy storage technologies must integrate sustainability concepts into their design. Notably, the incumbent LIB technology uses the reprotoxic solvent N-methyl pyrrolidone (NMP) to dissolve polyvinylidene fluoride (PVdF) as a binder. This solvent, of concern to human and ecological health, must be replaced with less toxic alternatives. Accordingly, the objective of this study was to determine which potential solvents, compatible with PVdF binder within the cathode processing of LIBs, could replace NMP. This study followed the U.S. National Research Council’s Framework to Guide Selection of Chemical Alternatives, and thus assembled and compared data concerning ecological and human hazards, performance, and cost. Five solvents were assessed as alternatives to NMP, derived from an analysis of 948 cells of data (708 cells of hazard data, 54 cells of performance data, and 186 cells of cost data). Triethyl phosphate (TEP) and N-N’-dimethylpropyleneurea (DMPU) are found to exhibit reprotoxic properties, and dimethylsulfoxide (DMSO) raised concerns in all three data categories studied. The most promising alternatives to NMP were dihydrolevoglucosenone (Cyrene) and γ-valerolactone (GVL). With demand for sustainable energy storage growing, the results of this study aim to guide research and innovation of LIB technologies while avoiding regrettable substitutions in developing NMP-free LIBs.

Tailoring of Electrocatalytic Oxygen Evolution Reaction Performance of 2D Conductive Co-Catecholate Metal-Organic Frameworks

Herein, we report the microwave hydrothermal synthesis of highly porous and conductive 2D Co-catecholate MOFs (Co-CATs) in the absence (Co-CAT-WO) and presence (Co-CAT-W) of N-methyl-2-pyrrolidone (NMP) polar solvent, and the study of these Co-CATs as electrocatalysts for oxygen evolution reaction (OER). The OER performance of Co-CAT-WO and Co-CAT-W is compared. The as-synthesized Co-CATs exhibit a 2D layered hexagonal structure. The electrical conductivity of Co-CAT-WO and Co-CAT-W is 6.9 and 5.8 S/m, respectively. The good conductivity and porous structure can initiate charge transport to achieve better OER performance under the 4e--transfer process. The as-prepared Co-CAT-WO and Co-CAT-W, respectively, show an overpotential of 455 and 424 mV at 10 mA/cm2 after performing the durability and chronoamperometry experiments for 13 h in 1M KOH. From the electrochemical studies, it is apparent that the Co-CAT-W exhibits better OER performance with low overpotential, high current density, and excellent stability over extended cycling. Moreover, the lower HOMO-LUMO gap for Co-CAT-W than that of the Co-CAT-WO endorses its better electrocatalytic activity. The post-OER results show that the Co-CAT-W electrocatalyst acts as a "precatalyst" rather than the original catalyst, and it undergoes electrochemical transformation to metal hydroxide and metal oxyhydroxide after the OER studies, promoting the OER kinetics. The findings of this work offer valuable insights into the synthetic strategies for developing 2D conducting metal-catecholate MOF catalysts for efficient and sustainable OER processes, which is crucial in water splitting for sustainable energy production.

The Pesticide Paradox: Metabolomics Insights into N-Methyl-2-Pyrrolidone (NMP) Exposure as a Culprit of Infant Undernourishment

The Pesticide Paradox: Metabolomics Insights into N-Methyl-2-Pyrrolidone (NMP) Exposure as a Culprit of Infant Undernourishment

Facile Synthesis, Sintering, and Optical Properties of Single-Nanometer-Scale SnO2 Particles with a Pyrrolidone Derivative for Photovoltaic Applications

We investigate the preparation of mesoscopic SnO2 nanoparticulate films using a Sn(IV) hydrate salt combined with a liquid pyrrolidone derivative to form a homogeneous precursor mixture for functional SnO2 nanomaterials. We demonstrate that N-methyl-2-pyrrolidone (NMP) plays a crucial role in forming uniform SnO2 films by both stabilizing the hydrolysis products of Sn(IV) sources and acting as a base liquid during nanoparticle growth. The hydrolysis of Sn(IV) was controlled by adjusting the reaction temperature to as low as 110 °C for 48 h. High-resolution TEM analysis revealed that highly crystalline SnO2 nanoparticles, approximately 3–5 nm in size, were formed. The SnO2 nanoparticles were deposited onto F-doped SnO2 glass and converted into dense particle films through heat treatments at 400 °C and 500 °C. This pyrrolidone-based nanoparticle synthesis enabled the production of not only crystallized SnO2 but also transparent and uniform films, most importantly by controlling the slow hydrolysis of Sn(IV) and polycondensation only with those two chemicals. These findings offer valuable insights for developing stable and uniform electron transport layers of SnO2 in mesoscopic solar cells, such as perovskite solar cells.

Enhancing performance and sustainability of lithium manganese oxide cathodes with a poly(ionic liquid) binder and ionic liquid electrolyte

Current battery production involves various energy intensive processes and the use of volatile, flammable and/or toxic chemicals. This study explores the potential for using a water-soluble and functional binder, poly(diallyldimethylammonium) (PDADMA) with diethyl phosphate (DEP) as a counter anion, for lithium manganese oxide (LMO) cathodes. By replacing the traditional polyvinylidene fluoride (PVDF) binder and its associated toxic N-methyl-2-pyrrolidone (NMP) solvent, PDADMA-DEP offers a more sustainable and cost-effective solution. Notably, PDADMA-DEP electrodes do not require high-temperature calendaring to achieve high performance unlike PVDF electrodes. X-ray Photoelectron Spectroscopy (XPS) indicated significant interactions between the binder and LMO that enhance stability and ion conduction. The PDADMA-DEP binder demonstrated excellent electrochemical rate capability up to 10C with the conventional organic liquid electrolyte (LP30), outperforming PVDF electrodes. The performance of both binders using a safer and non-volatile ionic liquid electrolyte, specifically 50 mol% LiFSI in N-trimethyl-N-propylammonium bis(fluorosulfonyl)imide, was also investigated to enhance the overall safety and environmental impact of the battery system. IL-based cells utilizing a PDADMA-DEP cathode binder demonstrated a 58 % capacity retention over 500 cycles at 0.5C when cycled at room temperature.

Precursor Ink Engineering to Implement Vacuum Extraction Method for Scalable Production of Perovskite Solar Cells.

Engineering perovskite precursor ink to widen the processing window is crucial to obtaining uniform, compact, and pinhole-free perovskite films at scale using industrially relevant solution coating techniques. Here, we introduce a ternary solvent system and systematically investigate the impacts of coordinating solvents, N-methyl-2-pyrrolidone (NMP) and N,N'-dimethylpropyleneurea (DMPU), on the physical properties of the slot-die-coated perovskite films and on the corresponding device performance. Tailoring NMP and DMPU concentrations in the precursor ink allows us to control the perovskite intermediate phase formation and widen the processing window, enabling the reproducible production of perovskite films with high photoelectrical quality at scale. Using the optimized precursor ink, we demonstrate slot-die-coated perovskite minimodules with power conversion efficiencies of 19 and 16% on 56 and 100 cm2 substrates, respectively.

Towards More Sustainable Schiff Base Carboxylate Anodes for Sodium-Ion Batteries.

Bismine sodium salt (BSNa), a Schiff base with two sodium carboxylates, has shown promising electrochemical performance as an anode material. However, its synthesis involves toxic reagents and generates impurities, requiring significant solvent use for purification. This study introduces a novel synthetic method using sodium hydroxide as the sole reagent, which acts as both a base and Na source in the ion exchange step. With this procedure, we reduce the amounts of chemicals, diminish toxicity, improve the purity of the target compound, and use less solvent while maintaining comparable electrochemical performance. Additionally, the procedure is carried out under anhydrous conditions that avoid the undesirable hydrolysis of the imine linkages. In a previous report, the processing of the composite electrode was not established. In this article, we address this issue; the electrochemical performance, specifically the rate capability, is enhanced by processing the electrodes in laminate form rather than powder. As alternative to N-methyl-2-pyrrolidone (NMP), a common but disadvantageous solvent in laminate processing, other solvents were explored by testing acetone (DMK), methylisopropylketone (MIPK), and a DMK-NMP mixture. The remarkable electrochemical performance (specific capacity of 260-280 mAh/g, and capacity retentions higher than 84% at 1C (260 mA/g) remained consistent across these solvents. Furthermore, we investigated replacing copper with aluminum as the current collector to reduce costs and increase the energy density of the battery. While aluminum performed comparably to copper at low specific currents C/10 (26 mA/g), it showed a significant shift in the redox process potentials at higher specific currents.

Investigation of the influence of fluorine on metal elution from cathodic active material liberated from spent lithium-ion batteries with a focus on the underwater electrical pulse method

Abstract As a promising candidate to separate the cathode materials and aluminum foils, the underwater electrical pulse method is an environmentally friendly method that can effectively liberate cathodic active material in a very short time. However, performing the electric pulse separation in aqueous media may cause the release of fluoridated elements, which may come from fluoridated components formed during battery cycles or due to the remaining electrolyte within the cathode particles. Thus, the purpose of this work is to study the solution obtained after pulse discharge in terms of fluoridated entities, to understand their effect on the elution of active cathodic materials. Herein, to investigate the potential source of F and its possible effects on metal extraction, leaching experiments were conducted in the presence of different fluoride concentrations with a solid/liquid ratio of 0.5g/L under circumneutral pH conditions (pH range: 5.7-7.5) using a spent nickel-cobalt-manganese lithium battery sample liberated by N-Methyl pyrrolidone. The results show that the amounts of F ions in solution increased with leaching time, with a maximum value close to 2.34 ppm F obtained after 2 h. It is worth noting that the presence of fluoride-ion can promote the elution of aluminum, as a maximum concentration of 1.85 ppm Al was observed at 2 h in the presence of 40 ppm F, whereas only about 0.32 ppm Al was detected in the case of fluoride-free solutions. Consequently, our results demonstrated that the amounts of transition metals (Ni, Mn, and Co) released towards liquid changed very little irrespective of the concentrations of dissolved fluoride, suggesting that the released F ions do not affect metals elution.

Lead Iodide Redistribution Enables In Situ Passivation for Blading Inverted Perovskite Solar Cells with 24.5% Efficiency.

Blade-coating stands out as an alternative for fabricating scalable perovskite solar cells. However, it demands special control of the precursor composition regarding nucleation and crystallization and currently exhibits lower performance than the spin-coating process. It is mainly the resulting film morphology and excess lead iodide (PbI2) distribution that influences the optoelectronic properties. Here, the effectiveness of introducing N-Methyl-2-pyrrolidone (NMP) to regulate the structure of the perovskite layer and the redistribution of PbI2 is found. The introduction of NMP leads to the accumulation of excess PbI2, mainly on the top surface, reducing residual PbI2 at the perovskite buried interface. This not only facilitates the passivation of perovskite grain boundaries but also eliminates the potential degradation of the PbI2 triggered by light illumination in the perovskite buried interface. The optimized NMP-modified inverted perovskite solar cell achieves a champion efficiency of 24.5%, among the highest reported blade-coated perovskite solar cells. Furthermore, 13.68cm2 blading perovskite solar modules are fabricated and demonstrate an efficiency of up to 20.4%. These findings underscore that with proper modulation of precursor composition, blade-coating can be a feasible and superior alternative for manufacturing high-quality perovskite films, paving the way for their large-scale applications in photovoltaic technology.

Enabling high-performance organic copper metal batteries via ultralow-concentration iron ion redox

The stable coordination of chloride ions in aqueous CuCl2 electrolyte results in the coexistence of Cu2+ and Cu+, rendering it a promising electrolyte capable of facilitating various redox reactions. However, the significant challenge arises from the strong combination reaction between aqueous CuCl2 electrolyte and metallic copper, hindering the development of cost-effective copper metal batteries based on variable-valence copper ion electrolytes. Herein, utilizing the synergistic effect of electrolytes, a novel copper metal battery is constructed with a 1 m Cu(OTf)2 + 0.05 m FeCl3 organic electrolyte based on the N-methyl-2-pyrrolidone (NMP) system. Mechanism investigations reveal that the organic electrolyte achieves three-step stable redox reactions in both Cu||PANI battery and Cu||CuFe-PBA battery. Intriguingly, the coordination of ultralow-concentration chloride ions effectively stabilizes Cu+ and enables two independent redox reactions (Cu2+/Cu+ and Cu+/Cu0). Concurrently, ultralow-concentration of Fe3+ facilitates the mutual conversion to Fe2+, which is very rare redox process in electrochemical energy storage. Consequently, the designed organic copper ion electrolyte with 0.05 m FeCl3 additive exhibits outstanding thermodynamic stability towards metallic copper, enabling the Cu||Cu symmetric battery to maintain a cycle lifespan of 4000 h (∼167 days) at 0.5 mA h cm−2, which is the highest one among copper-ion batteries up to date. Benefitting from the redox of Fe3+/Fe2+, the Cu||PANI battery exhibits a high capacity retention of 85.60 % after 2000 cycles. This work opens up unprecedented possibilities of optimizing electrolyte formulations for copper metal batteries.

Real-time observation of crystals growth under optical microscopy: A self-assembly process of organic-inorganic intercalation composites driven by electrostatic interaction

The utilization of self-assembly through non-covalent forces such as electrostatic interactions and hydrogen bonds offers an effective strategy for the construction of organic-inorganic intercalation composite materials. Although self-assembly strategies hold significant potential, the embedding of organic guest molecules within inorganic host materials through self-assembly processes remains unexplored. In this work, the real-time observation of the self-assembly process of organic-inorganic intercalation composite materials has been achieved using confocal microscopy. We found that methylene blue intercalated molybdenum oxide (MB-MoO3-x) can be synthesized using a mild solution-phase self-assembly reaction and proposed a potential crystal growth model. Our findings indicate that the intercalation of MB remarkably increases the interlayer spacing of MoO3, that causes a transition from an amorphous to a more ordered crystalline structure. Adjusting UV irradiation and N-Methyl-2-pyrrolidone (NMP) content, the particle size of MB-MoO3-x could be controlled, ranging from 400 nm to 500 μm. Characterization techniques such as XPS, FTIR and Raman spectroscopy revealed that the self-assembly of MB with MoO3 is driven by non-covalent electrostatic interactions. Our research provides significant insights into the self-assembly mechanism of organic-inorganic intercalation composite materials, aiding the development of materials that combine the stability and electronic utility of inorganic metal oxides with the chemical diversity and functionality of organic molecules.

Lipoteichoic Acid from Lacticaseibacillus rhamnosus GG as a Novel Intracanal Medicament Targeting Enterococcus faecalis Biofilm Formation.

The demand for safe and effective endodontic medicaments to control Enterococcus faecalis biofilms, a contributor to apical periodontitis, is increasing. Recently, lipoteichoic acid (LTA) of family Lactobacillaceae has been shown to have anti-biofilm effects against various oral pathogens. Preliminary experiments showed that LTA purified from Lacticaseibacillus rhamnosus GG (Lgg.LTA) was the most effective against E. faecalis biofilms among LTAs from three Lactobacillaceae including L. rhamnosus GG, Lacticaseibacillus casei, and Lactobacillus acidophilus. Therefore, in this study, we investigated the potential of Lgg.LTA as an intracanal medicament in human root canals infected with E. faecalis. Twenty eight dentinal cylinders were prepared from extracted human teeth, where two-week-old E. faecalis biofilms were formed followed by intracanal treatment with sterile distilled water (SDW), N-2 methyl pyrrolidone (NMP), calcium hydroxide (CH), or Lgg.LTA. Bacteria and biofilms that formed in the root canals were analyzed by scanning electron microscopy and confocal laser scanning microscopy. The remaining E. faecalis cells in the root canals after intracanal medicament treatment were enumerated by culturing and counting. When applied to intracanal biofilms, Lgg.LTA effectively inhibited E. faecalis biofilm formation as much as CH, while SDW and NMP had little effect. Furthermore, Lgg.LTA reduced both live and dead bacteria within the dentinal tubules, indicating the possibility of minimal re-infection in the root canals. Collectively, intracanal application of Lgg.LTA effectively inhibited E. faecalis biofilm formation, implying that Lgg.LTA can be used as a novel endodontic medicament.

Removal of trace Na and K metal ions by resin-grafted crown ether for electronic-grade N-methyl pyrrolidone purification

The semiconductor industry’s rapid evolution necessitates ultra-high-purity N-methyl pyrrolidone (NMP) as an essential electronic-grade solvent. The development of an efficient coordination material to reduce trace metal ions, particularly Na and K metal ions, to below 1 ppb in NMP solution is a significant challenge. To address this, a novel coordination material, St-DVB-g-ACE, has been developed for the removal of Na and K metal ions from NMP. The material was synthesized by grafting 4′-aminobenzo-15-crown-5-ether onto a strong acid gel resin. The resulting St-DVB-g-ACE-3 exhibited excellent coordination performance for Na and K metal ions, with maximum Langmuir adsorption capacities reaching 20,000 μg/g and 33,333 μg/g, respectively. Of particular interest was the ability of St-DVB-g-ACE-3 to reduce all trace metal ions in industrial-grade NMP to below 1 ppb within a fixed bed column, achieving the stringent requirements for electronic-grade NMP at the G3 level. Additionally, the absorbent enhances the purity of NMP from 99.82 % to 99.84 %, indicating that the material is not dissolved and can exist stably in NMP. Its excellent recyclability and reproducibility make it highly practical for industrial use. Density functional theory (DFT) simulation, complemented by spectral analyses, revealed the interaction force and thermodynamic properties between Na and K metal ions and crown ether ring, and illustrated the interaction between anionic sulfonic group (−SO3−) and metal ions. The prepared resin-grafted crown ether adsorbents are highly effective in the thorough removal of trace metal ions from NMP solution, offering a novel and effective method for the production of electronic-grade NMP.

Enhancing precursor stability with suitable additives to enable blade-coating of organic-inorganic hybrid perovskites at room temperature for efficient perovskite solar modules

In this study, room temperature blade coating organic-inorganic hybrid perovskite (OIHP) films with the precursors made of adding additives such as dimethyl sulfoxide (DMSO), N,N-dimethylformamide (DMF), and N-methyl-2-pyrrolidone (NMP) to the volatile solvent of 2-methoxylethanol (2-ME) were explored. Unlike NMP, DMSO and DMF interact with the perovskites to form Lewis adducts, suggesting important factors beyond the Gutmann donor number and dielectric constant, such as molecular structure, influence adduct formation. The OIHP solar cells made of the precursors with optimized amount of DMSO, DMF and NMP showed the efficiency of 16.5 %, 16.1 % and 8.3 %, respectively. After optimizing the blade-coating process for OIHP film formation by using the Taguchi's method, the optimized OIHP solar modules (active area = 25.2 cm2) achieve PCEs of 14.6 % and 14.1 % with the precursor added 20 mol% DMSO and 30 mol% DMF, respectively. Moreover, the precursor added with DMF demonstrates better storage stability than that of DMSO, achieving the best module PCE of 13.4 % fabricated from the 3-day stored DMF-added precursors, while the module fabricated from the DMSO-added precursor shows a PCE of 9.1 %.

Investigation on microscopic pore structure optimization and Lattice Boltzmann seepage law in coal modified by N-methylpyrrolidone composite solvents

This study evaluated the impact of composite solvents (1-butyl-3-methylimidazolium tetrafluoroborate [Bmim]BF4, sodium dodecyl sulfate (SDS), and N-methyl pyrrolidone (NMP)) on microscale pore-fracture structures and mesoscopic gas seepage in coal samples; by employing fractal theory and the Lattice Boltzmann method (LBM). Under combined application of three composite solvents: (1) there was a substantial 23.66 % increase in the scanning electron microscopy fractal dimension of the samples, which signifies enhanced complexity and nonhomogeneity of the samples; (2) the percentages of mesopores and macropores in the samples experienced a 10.64 % increase, resulting in a 20.45 % increase in overall porosity; (3) the effective pore fractal dimension (Da) and seepage pore fractal dimension (Ds) exhibited respective decreases of 3.05 % and 0.57 %; and (4) the average gas seepage velocity substantially increased by 53.57 %, with the optimal flow channel development position along the x-direction being closer to the exit (x = 170). These phenomena were attributed to the following: (1) introducing SDS reagents enhanced coal hydrophilicity; (2) NMP and [Bmim]BF4 aqueous solvents could more easily infiltrate the minuscule pores; (3) the synergy of the composite solvents disrupted the pore-fracture structures of the coal matrix, leading to a substantial increase in the aperture and area of the open pores; and (4) this process enhanced the connectivity, consequently increasing the average seepage velocity.

Opening the Hysteresis Loop in Ferromagnetic Fe3GeTe2 Nanosheets Through Functionalization with TCNQ Molecules.

Ferromagnetic metal Fe3GeTe2 (FGT), whose structure exhibits weak van-der-Waals interactions between 5-atom thick layers, was subjected to liquid-phase exfoliation (LPE) in N-methyl pyrrolidone (NMP) to yield a suspension of nanosheets that were separated into several fractions by successive centrifugation at different speeds. Electron microscopy confirmed successful exfoliation of bulk FGT to nanosheets as thin as 6 nm. The ferromagnetic ordering temperature for the nanosheets gradually decreased with the increase in the centrifugation speed used to isolate the 2D material. These nanosheets were resuspended in NMP and treated with an organic acceptor, 7,7,8,8-tetracyano-quinodimethane (TCNQ), which led to precipitation of FGT-TCNQ composite. The formation of the composite material is accompanied by charge transfer from the FGT nanosheets to TCNQ molecules, generating TCNQ•- radical anions, as revealed by experimental vibrational spectra and supported by first principles calculations. Remarkably, a substantial increase in magnetic anisotropy was observed, as manifested by the increase in the coercive field from nearly zero in bulk FGT to 1.0 kOe in the exfoliated nanosheets and then to 5.4kOe in the FGT-TCNQ composite. The dramatic increase in coercivity of the composite suggests that functionalization with redox-active molecules provides an appealing pathway to enhancing magnetic properties of 2D materials.

Opening the Hysteresis Loop in Ferromagnetic Fe3GeTe2 Nanosheets Through Functionalization with TCNQ Molecules

Ferromagnetic metal Fe3GeTe2 (FGT), whose structure exhibits weak van‐der‐Waals interactions between 5‐atom thick layers, was subjected to liquid‐phase exfoliation (LPE) in N‐methyl pyrrolidone (NMP) to yield a suspension of nanosheets that were separated into several fractions by successive centrifugation at different speeds. Electron microscopy confirmed successful exfoliation of bulk FGT to nanosheets as thin as 6 nm. The ferromagnetic ordering temperature for the nanosheets gradually decreased with the increase in the centrifugation speed used to isolate the 2D material. These nanosheets were resuspended in NMP and treated with an organic acceptor, 7,7,8,8‐tetracyano‐quinodimethane (TCNQ), which led to precipitation of FGT‐TCNQ composite. The formation of the composite material is accompanied by charge transfer from the FGT nanosheets to TCNQ molecules, generating TCNQ•– radical anions, as revealed by experimental vibrational spectra and supported by first principles calculations. Remarkably, a substantial increase in magnetic anisotropy was observed, as manifested by the increase in the coercive field from nearly zero in bulk FGT to 1.0 kOe in the exfoliated nanosheets and then to 5.4 kOe in the FGT‐TCNQ composite. The dramatic increase in coercivity of the composite suggests that functionalization with redox‐active molecules provides an appealing pathway to enhancing magnetic properties of 2D materials.