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The formation of the solid electrolyte interphase (SEI) on HC composite electrodes plays a crucial role in enhancing the performance and operational stability of sodium (Na+) ion batteries. It has been demonstrated that for HC anodes improved electrochemical performance, e. g., increase in coulombic efficiency (CE) and improved rate performance have been achieved in ether‐based electrolytes. Here, we investigate spray‐coated HC composite electrodes charged at low and high current rates in 1 M sodium hexafluorophosphate (NaPF6) in diglyme using half‐cell experiments. The pristine and cycled HC anodes were examined in terms of conductivity and their electrochemical properties after cycling. In 1 M NaPF6 ether‐based electrolyte, the spray‐coated HC composite electrodes (film thickness approx. 22.0 μm with an active mass loading of approx. 2.0 mg cm−2) reached a discharge capacity of 431 mA h g−1 at 0.1 C that stays constant for 40 cycles, which is substantially higher than that obtained in carbonate‐based electrolytes. We investigated the formed interphase using conductive atomic force microscopy (c‐AFM), scanning electrochemical microscopy (SECM), X‐ray photoelectron spectroscopy (XPS) and time‐of‐flight secondary‐ion mass spectrometry (ToF‐SIMS), revealing distinct differences for longer cycling and at varying current rates which indicates that the properties of the formed SEI layers are influenced by the formation conditions. [ABSTRACT FROM AUTHOR]

Polyfluoroaromatic zinc compounds obtained from bromopolyfluoroarenes in diglyme react with oxalyl chloride in this solvent both in the presence and in the absence of CuI to give 1,2-bis(polyfluoroaryl)ethane-1,2-diones. [ABSTRACT FROM AUTHOR]

In the copper-mefenamate complex tetrakis[μ-2-(2,3-dimethylanilino)benzoato-κ²O:O']bis[aquacopper(II)]-1-methoxy-2-(2-methoxyethoxy)ethane (1/2), [Cu2(C15H14NO2)4(H2O)2]·2C6H14O3, the asymmetric unit comprises a CuII cation coordinated to two mefenamate ligands solvated with a water molecule and a diglyme molecule. The complex adopts a paddlewheel motif and is compared to structural analogues crystallized with dimethylformamide and dimethyl sulfoxide. [ABSTRACT FROM AUTHOR]

A micro segmented-flow approach was utilized for the isolation soil bacteria that can degrade synthetic polymers as polyethylene glycols (PEG) and polyacrylamide (PAM). We had been able to obtain many strains; among them, five Achromobacter spanius strains from soil samples of specific sampling sites that were connected with ancient human impacts. In addition to the characterization of community responses and isolating single strains, this microfluidic approach allowed for investigation of the susceptibility of Achromobacter spanius strains against three synthetic polymers, including PEG, PAM, and Polyvinylpyrrolidone (PVP) and two organic solvents known as 1,4-dioxane and diglyme. The small stepwise variation of effector concentrations in 500 nL droplets provides a detailed reflection of the concentration-dependent response of bacterial growth and endogenous autofluorescence activity. As a result, all five strains can use PEG600 as carbon source. Furthermore, all strains showed similar dose-response characteristics in 1,4-dioxane and diglyme. However, significantly different PAM- and PVP-tolerances were found for these strains. Samples from the surface soil of prehistorical rampart areas supplied a strain capable of degradation of PEG, PVP, and PAM. This study demonstrates on the one hand, the potential of microsegment flow for miniaturized dose-response screening studies and its ability to detect novel strains, and on the other hand, two of five isolated Achromobacter spanius strains may be useful in providing optimal growth conditions in bioremediation and biodegradation processes. [ABSTRACT FROM AUTHOR]

Sodium-ion batteries (SIBs) are considered promising candidates for future grid energy storage, with hard carbons emerging as key commercial anode materials. This study presents a novel approach to synthesize N-doped hard carbons via co-hydrothermal treatment of vine shoots and pig manure and subsequent thermal annealing of the resulting hydrochar. This method enhances the development of micro- and ultra-microporosity in the synthesized hard carbons, with nitrogen, and to a lesser extent phosphorus and sulfur, introduced as doping elements. Furthermore, the incorporation of hydrochloric acid during the hydrothermal step promotes biomass hydrolysis, leading to increased mesoporosity and the formation of microsphere clusters. In the realm of electrochemical performance, an investigation into various ester- and ether-based electrolytes has revealed NaPF 6 in diglyme as the best formulation, thanks to its thinner and more stable solid electrolyte interface (SEI). Using this electrolyte, the best-performing electrode showed an initial Coulombic efficiency (ICE) of 73 %, with reversible capacities of 239, 180, 86, and 57 mAh g−1 at 0.1, 1, 5, and 10 A g−1, respectively. In addition, the electrode exhibited a remarkable capacity retention of 88 % after 250 cycles as well as a compatible behavior when paired with a NVPF-based cathode. [Display omitted] • Hydrothermal pretreatment boosts the performance of vine shoots-based anodes. • Pig manure was successfully valorized as hydrothermal medium. • Pig manure improves the capacity and stability of the resulting HC-based anodes. • HCl addition promotes mesoporosity and the formation of microsphere clusters. • The performance of HCs further improves when using diglyme-based electrolytes. [ABSTRACT FROM AUTHOR]

Metal free catalysis has emerged as a viable alternative for transition metal based catalysts for enabling different chemical processes, particularly for de/hydrogenation reactions. Herein, employing theoretical studies we reveal the unexpected Frustrated Lewis Pair like reactivity of a boron based catalyst, 9,10‐dichlorodiboraanthracene and the ethereal solvent to enable dehydrogenation of ammonia‐borane (NH3BH3, AB) under moderate conditions. The mechanistic channels thus uncovered reveal that the boron catalyst abstracts a hydride from NH3BH3 followed by crucial stabilization of the NH3BH2+ moiety by the nucleophilic action of the solvent. H2 is released by the combination of hydride and proton from the borohydride moiety and the solvated NH3BH2+ respectively. Catalysis becomes unfeasible if the Lewis base‐like action of the ethereal solvent is not taken into consideration. Thus, it is suggested that the clandestine partnership of the Lewis Acid, Boron catalyst and the Lewis Base, ethereal solvent, i. e. FLP like action enables dehydrogenation of NH3BH3 in the instant case. [ABSTRACT FROM AUTHOR]

The sodium‐air battery offers a sustainable, high‐energy alternative to lithium‐ion batteries. Discharge in the cell containing glyme‐based electrolytes can lead to formation of large cubic NaO2 particles via a solution‐precipitation mechanism. While promising, high rates result in sudden death. The exact nature of the discharge product has been a matter of contention, and Na2O2 has never been directly detected in a dry glyme Na−O2 cell. If Na2O2 were to form during discharge in the Na−O2 cell it would have a detrimental impact on cell performance. Here we show that Na2O2 forms during discharge at high overpotential in the glyme‐based Na−O2 batteries. Na2O2 formation is confirmed by spectroscopic and electrochemical analysis and electron microscopy demonstrates that it results in thin insulating films at the electrode surface. The formation of these thin films results in rapid cell death during discharge, introducing an inherent chemical limitation to the Na−O2 battery. [ABSTRACT FROM AUTHOR]

An alternate method for diglycolic acid preparation from chloroacetic acid and NaOH in an anhydrous mixture of diethylene glycol diethyl ether (Glyme) and dimethyl sulfoxide (DMSO) at room temperature was proposed. Our study examined the effectiveness of electrodialytic (ED) desalination of the obtained post-reaction mixture (i.e., diluate) for recovery of diglycolic acid, and the separation of organic solvents. The effect of the diglycolic acid concentration and DMSO and Glyme recovery on desalination efficiency, solvent transport rates, and energy consumption were investigated. We showed that ED could be successfully applied for the desalination, concentration, and recovery of diglycolic acid from the post-reaction mixtures. Furthermore, this application allows for the synthesis of diglycolic acid in an anhydrous environment. [Display omitted] • Development of new synthesis or sustainable technological route using electrodialysis • Recovery of polar and non-ionic organic solvent(s) under mild conditions • Limiting the use of evaporation techniques for less volatile solvents • Recovery of waste by-products obtained in synthesis that are free from pollutants • The ionic by-products may be reused in other technologies. [ABSTRACT FROM AUTHOR]

This work presents for the first time a new diglyme‐based gel polymer (DOBn‐GPE) suitable for Na‐based energy storage devices. The DOBn‐GPE, which contains a methacrylate‐based polymer, exhibited an excellent high ionic conductivity (2.3 mS cm−1 at 20 °C), broad electrochemical stability (>5.0 V), and high mechanical stability. DOBn‐GPE could be successfully used for the realization of Na‐ion capacitors, sodium‐metal batteries, and sodium‐ion batteries, displaying performance comparable with those of systems containing liquid electrolytes at room temperature and at 60 °C. The results of these investigation indicated that the development of diglyme‐based gel polymer electrolytes represents a promising strategy for the realization of advanced Na‐based energy storage devices. [ABSTRACT FROM AUTHOR]

Copper phosphide (Cu3P) is a potentially high volumetric capacity conversion electrode for the use in Li-ion as well as in Na-ion batteries. Here, we study the lithium and sodium storage properties of Cu3P/Carbon (Cu3P/C) composites containing 70 wt% Cu3P and 30 wt% carbon black. Cu3P is prepared by reactive ball milling from the elements while in a second step Cu3P is mixed with carbon black by non-reactive ball milling. Structure and morphology are characterized by X-ray diffraction (XRD) as well as scanning and transmission electron microscopy (SEM, TEM). The electrochemical properties are studied in Li and Na half cells with different types of electrolytes based on carbonates (EC:DMC mixture) or diglyme, with the latter clearly leading to better results such as higher capacity, better cycle life and smaller polarization. After 120 cycles, the Li-cell showed a capacity of 210 mAh g−1 while around 120 mAh g−1 were found for the Na cell. The contribution of the carbon black is negligible in case of the Li cell while it becomes an important factor in the Na cell. Electrode expansion/shrinkage of the electrode during cycling (“breathing”) as determined by in situ dilatometry is fairly constant in diglyme electrolytes while rapid fading is observed in carbonate electrolytes.

Glymes present a promising new group of electrolyte solvents for sodium‐ion batteries. Not only do they have excellent electrolyte solvent properties but they also enable the intercalation of sodium into graphite as sodium‐glyme complexes, a reaction which is not possible for sodium in conventional electrolyte solvents. However, little is known about the solution structure of these complexes, especially for sodium salts, and why glymes enable this process while other commonly used electrolyte solvents do not. Here, a combination of neutron total scattering and empirical potential structure refinement was used to characterize the solvent structure around the ions, for a NaPF6 solution in diglyme. This showed that 82 % of the sodium ions are bound as Na+(diglyme)2 complexes, the conformation needed for intercalation into graphite, with the rest forming various contact ion pairs. The model also showed that very weak hydrogen bonding interactions exist between the anion and the diglyme molecules. [ABSTRACT FROM AUTHOR]

It was shown by ATR FTIR, XRD and 11B MAS NMR methods that increasing contents of sodium polyborate and sodium carbonate impurities were formed in solid sodium borohydride upon its storage and contact with the air. To increase the NaBH 4 purity after storage, it was re-crystallized in diglyme using the well-known Brown's procedure. The purification efficiency was further improved by ammonia treatment during NaBH 4 dissolution. It was found that the advantages of using the gaseous ammonia consisted in an increased NaBH 4 solubility in diglyme and a more efficient reduction in the content of impurities to form a material consisting of uniform highly dispersed particles of the hydride having a regular cubic shape. It was found for the process of catalytic hydrolysis of NaBH 4 that the rate of hydrogen generation and its yield increased with the decreasing content of impurities. These results demonstrate the importance of investigations aimed at improving the existing methods of NaBH 4 purification and creating new ones. Image 1 • Рolyborate and carbonate of sodium are formed upon contact of NaBH 4 (SBH) with air. • SBH purification was applied using its re-crystallization from diglyme (DG) solution. • Gaseous NH 3 passed into DG+SBH increases the solubility of SBH. • This leads to formation of dispersed cubic shaped particles of SBH of high purity. • Decreasing content of impurities improves parameters of SBH catalytic hydrolysis. [ABSTRACT FROM AUTHOR]

This work reports the facile synthesis of a Sn–P composite combined with nitrogen doped hard carbon (NHC) obtained by ball‐milling and its use as electrode material for sodium ion batteries (SIBs). The "Sn4P3"/NHC electrode (with nominal composition "Sn4P3":NHC = 75:25 wt%) when coupled with a diglyme‐based electrolyte rather than the most commonly employed carbonate‐based systems, exhibits a reversible capacity of 550 mAh gelectrode−1 at 50 mA g−1 and 440 mAh gelectrode−1 over 500 cycles (83% capacity retention). Morphology and solid electrolyte interphase formation of cycled "Sn4P3"/NHC electrodes is studied via electron microscopy and X‐ray photoelectron spectroscopy. The expansion of the electrode upon sodiation (300 mAh gelectrode−1) is only about 12–14% as determined by in situ electrochemical dilatometry, giving a reasonable explanation for the excellent cycle life despite the conversion‐type storage mechanism. In situ X‐ray diffraction shows that the discharge product is Na15Sn4. The formation of mostly amorphous Na3P is derived from the overall (electro)chemical reactions. Upon charge the formation of Sn is observed while amorphous P is derived, which are reversibly alloying with Na in the subsequent cycles. However, the formation of Sn4P3 can be certainly excluded. [ABSTRACT FROM AUTHOR]

Conversion materials are promising to improve the energy density of sodium‐ion‐batteries (NIB). Nevertheless, they suffer from the drawback of phase transitions and pronounced volume changes during cycling, which causes cell instability. When using these types of electrodes, all cell‐components have to be adjusted. In this study, a tremendous influence of the electrolyte solution on Sb2O3 conversion electrodes for NIBs is discussed. Solutions based on three solvents and solvent combinations established for NIBs, ethylene carbonate/dimethyl carbonate (EC/DMC), EC/DMC+5 % fluoroethylene carbonate (FEC), and diglyme, lead to a massively divergent electrochemical behavior of the same Sb2O3 electrode. Sb2O3 demonstrates the highest stability in solutions containing FEC, because this component forms a flexible, protecting surface film that prevent disintegration. One key finding of this work is that electrolyte solutions based on ether solvents like diglyme can remove Sb‐ions from Sb2O3 during cycling. Diglyme has the ability to coordinate and extract Sb3+ during the oxidation of Sb2O3. This leads to contaminations of all cell components and a strong capacity loss together with an irregular electrochemical signature. Due to its poor reactivity at low potentials, diglyme forms a thin or even no surface layer. Thereby, there are no protecting films on the Sb2O3 electrodes that can avoid Sb3+ ion dissolution. A critical examination of the electrolyte solutions components' impact is essential to match them with conversion reaction anodes. [ABSTRACT FROM AUTHOR]

Lithium and sodium thiophosphates (and related compounds) have recently attracted attention because of their potential use as solid electrolytes in solid‐state batteries. These compounds, however, exhibit only limited stability in practice as they react with the electrodes. The decomposition products partially remain redox active hence leading to excess capacity. The redox activity of thiophosphates is explicitly used to act as electrode for sodium‐ion batteries. Copper thiophosphate (Cu3PS4) is used as a model system. The storage behavior between 0.01 and 2.5 V versus Na+/Na is studied in half cells using different electrolytes with 1 m NaPF6 in diglyme showing the best result. Cu3PS4 shows highly reversible charge storage with capacities of about 580 mAh g−1 for more than 200 cycles @120 mA g−1 and about 450 mAh g−1 for 1400 cycles @1 A g−1. The redox behavior is studied by operando X‐ray diffraction and X‐ray photoelectron spectroscopy. During initial sodiation, Cu3PS4 undergoes a conversion reaction including the formation of Cu and Na2S. During cycling, the redox activity seems dominated by sulfur. Interestingly, the capacity of Cu3PS4 for lithium storage is smaller, leading to about 170 mAh g−1 after 200 cycles. The results demonstrate that thiophosphates can lead to reversible charge storage over several hundred cycles without any notable capacity decay. [ABSTRACT FROM AUTHOR]

Diethylene glycol dimethyl ether (DGM), also known as diglyme, has a very high cetane number with fuel-bound oxygen of up to 36%, it has strong potential to reduce diesel emissions. This work is an investigation of the turbocharged diesel engine's emissions and performance parameters using coconut biodiesel-diglyme-diesel blends. Coconut biodiesel was used as an oxygenated fuel, while DGM was utilised as an oxygenated additive for its excellent cetane number and higher fuel-bound oxygen. The reason for adding diglyme to coconut biodiesel blends is to study the influence of cetane number and fuel-bound oxygen on performance, combustion and emission characteristics. There were five fuels tested in this study. To compare the performance, combustion and emissions data, a regular diesel was used as a base fuel. The neat diesel (100% diesel) and the neat coconut biodiesel (100% coconut biodiesel) were designated as diesel and Ox4 respectively. Blend of 70% diesel + 30% coconut biodiesel is abbreviated as Ox1, 70% diesel + 20% coconut biodiesel + 10% diglyme blend is abbreviated as Ox2, and 70% diesel + 10% coconut biodiesel + 20% diglyme blend is labelled as Ox3. All blending percentages were based on a volume basis. Engine experiments were performed with an unmodified Cummins 6-cylinder common rail diesel engine. The engine was fitted with precision measuring instruments. Using GT-Power, a one-dimensional (1-D) model was developed to examine some key performance parameters with those of experimental data. Most of the performance results show the variations between experimental and simulation data were within 10%. [ABSTRACT FROM AUTHOR]

This investigation explored engine performance, combustion and exhaust emissions with a new series of fuels for compression ignition engine. Three blends were formulated using diesel, tea tree oil and diethylene glycol dimethyl ether (DGM). Low grade tea tree oil is considered as waste, which was used as fuel in this investigation. DGM was blended with tea tree oil and diesel as an additive for its high oxygen content and cetane number. Diesel was chosen for comparison purposes. The three blends examined in this study were, 70-30-0, 70-20-10 and 70-10-20 in ratios of diesel-tea tree oil-DGM. A six-cylinder, four-stroke, turbocharged diesel engine was used in this experiment. Four different loads of 25%, 50%, 75%, 100% and 1500 revolutions per minute (rpm) were selected for the experiments. Engine performance parameters like efficiency, power, mean effective pressure and specific fuel consumption were considered. In-cylinder pressure, the rate of heat release, peak and boost pressure were considered for combustion parameters. Carbon monoxide (CO), nitrogen oxides (NOx), particulate matter (PM) and particulate number (PN) were considered for emission parameters. A maximum of 70% PM, 54% PN and 33% CO reductions were observed with three blends. However, 16% higher NOx emissions were observed with the blends. • Three tea tree oil blends were prepared using diglyme, diesel and tea oil. • The blends showed 0.49%–9% variations in performance parameters relative to diesel. • Compared to diesel, a maximum of 33% CO was reduced with tea tree oil blends. • Both PM and PN were reduced by 70% and 54% respectively with the blends. • A maximum of 16% higher NOx emissions was observed with the blends. [ABSTRACT FROM AUTHOR]

An approach to improve the Al3+ ion storage capacity of MoO3 in aqueous electrolyte is illustrated here. Graphene as conductive additive and diglyme as electrolyte additive play a pivotal and synergistic role in the improvement. Graphene-MoO3 composite exhibits stable capacity of 160 mAh g−1 over 100 cycles in diglyme mixed aqueous electrolyte with v/v mixing ratio of 50:50, whereas it delivers a capacity of only 75 mAh g−1 at the 100th cycle in pristine aqueous electrolyte. Besides, pristine MoO3 also demonstrates improved stability in diglyme mixed aqueous electrolyte. [ABSTRACT FROM AUTHOR]

The present study investigates the effect of blending oxygenate namely diethylene glycol dimethyl ether (diglyme) with minor vegetable oil namely rubber seed oil (RSO), babassu oil (BSO), and their blends in various proportions (R75B25, R50B50, and R25B75) on NOx-smoke trade-off and other engine characteristics. The tests were conducted on a commercial twin cylinder compression-ignition (CI) engine commonly used in tractors. The potential of the blends with diglyme is assessed based on performance, emission, and combustion characteristics of the engine at different load conditions. The tests were conducted at a constant speed of 1500 rpm maintaining the original injection timing and pressure. Compared to diesel, RSO, and BSO, and their blends exhibited inferior combustion due to poor physical properties like high viscosity and density. This resulted in a lower brake thermal efficiency with increase in HC, CO, and smoke emissions compared to diesel at all the load conditions. The augmented effect is observed with increase in BSO proportion for the blends and neat BSO. The poor combustion of minor vegetable oil and its blends lead to lower NOx emission as a result of lower in-cylinder temperature. To improve the performance and NOx-smoke trade-off, diglyme (DGM) was added with all the test fuels with the optimum share of 20% (by volume). Addition of DGM, increased brake thermal efficiency by 2-7% for all the test fuels due to improved combustion as a result of additional fuel bound oxygen in DGM and improved fuel blend properties. DGM addition reduced smoke, HC, and CO emission drastically with a slight increase in NOx emission compared to minor vegetable oil blends. The study shows that addition of DGM showed a promising note in NOx-smoke trade-off without affecting the other engine parameters. [ABSTRACT FROM AUTHOR]

Volatile complexes of fluorinated β-diketonates of neodymium(III) (hexafluoroacetylacetonates with glyme and diglyme and decafluoroacetylacetonate with glyme) were studied for applicability in lowbackground Nd-containing organic liquid scintillators. The complexes were prepared in one step and purified by vacuum sublimation. The composition of complexes was determined by 1H, 19F, and 13C NMR and IR spectroscopy and confirmed by elemental and functional analysis. It was shown that these adducts are suitable for the design of Nd-containing organic liquid scintillators with neodymium concentration of ~1-2 g/L. [ABSTRACT FROM AUTHOR]

• Vibrational spectroscopy is used to study the Mg:MgCl 2 :AlCl 3 electrolyte in diglyme and tetrahydrofuran. • The analysis of experimental data is supported by computational modeling. • The amount of dimeric aggregate [Mg 2 (μ-Cl) 3 ]+ is larger in tetrahydrofuran. The 2.39:1 Mg:MgCl 2 :AlCl 3 (MMAC)-tetrahydrofuran (THF) and 1:1.22 MMAC-diethylene glycol dimethyl ether (G2) electrolytes, which have been already investigated by electrochemical measurements, are studied in the current work by using experimental vibrational spectroscopy allied to ab initio molecular dynamics (AIMD) simulations of spectra. Raman data are practically identical to the 2:1 MgCl 2 :AlCl 3 (MACC)-THF and 3:5 MACC-G2 binary systems, except for a 330 cm−1 band, commonly assigned to [AlCl 3 (THF) 1-2 ] and/or [AlCl 2 ]+, which is absent for the THF-based ternary system. Subtle changes are also seen in the far-IR spectra, where a band at around 315 cm−1 shows strong dependence on the MgCl 2 content and so may be associated to the [Mg 2 (μ-Cl) 3 ]+ dimer. The monomeric species, [MgCl]+, is also observed in both electrolytes by means of IR bands at 270–285, 300 and 325–330 cm−1. The varied amounts of monomer and dimer seem to be related to the electrochemical activities determined for these ternary systems. [ABSTRACT FROM AUTHOR]

Abstract The promising application of Na-ion batteries in large-scale energy storage such as smart grid has encouraged intensive research on Na-based insertion compounds and their implementation in full Na-ion cells. Herein, the electrochemical performance of half cells using Na 0.66 Ni 0.33˗x Zn x Mn 0.67 O 2 (x = 0, 0.07 and 0.14) cathodes in diglyme-based electrolyte are first studied. For x = 0.07, high discharge capacities of 120 and 80 mA h g−1 at 15 and 150 mA g−1, respectively are measured, with stable operation voltage exceeding 4.0 V vs. Na+/Na and cycling life over 200 cycles. Moreover, DSC results of the charged positive electrodes confirmed that the thermal stability was improved distinctively by zinc modification. Also, graphitized petroleum coke exhibits good performance in diglyme-based electrolyte in terms of stable capacity (100 mA h g-1) over 200 cycles in a stable plateau within 0.5–1.0 V vs. Na+/Na. Thereafter, a full Na-ion battery using Na 0.66 Ni 0.26 Zn 0.07 Mn 0.67 O 2 cathode, diglyme electrolyte, and petroleum coke anode is proposed here that shows impressive performances, i.e. shows high discharge capacity of 86 mA h g-1 and 85% retention after 155 cycles. It is believed that diglyme-based electrolytes should be readily extended to other layered sodium oxide electrodes and their full cells. Graphical abstract Image 1 Highlights • A novel application of diglyme-based electrolyte for layered sodium oxide cathodes. • Comparable electrochemical performances to PC-based electrolyte were observed. • Na-ion full cells are built with Na 0.66 Ni 0.33˗x Zn x Mn 0.67 O 2 and petroleum coke. • Full cells show high energy density (258 W h kg-1) and electrochemical stability. [ABSTRACT FROM AUTHOR]

Diethylene glycol dimethyl ether (diglyme) is interesting as a representative of ethers with several oxygen bridges in the molecule and as a model alternative fuel. A comparative study of the diglyme radiolysis at room temperature and at the boiling point was carried out. Boiling facilitates the cleavage of internal C‒O bonds, weakens the cage effect and diglyme regeneration processes, and also favors radical exchange and dimerization reactions. Unlike radiolysis at room temperature, irradiation at the boiling point generates four times less unsaturated fragmentation products and practically does not give disproportionation products of heavy radicals. The yield of radiolytic decomposition of boiling diglyme reaches 15.5 molecules/100 eV, which is almost 1.5 times higher than at room temperature. [ABSTRACT FROM AUTHOR]

The radiolysis of diethylene glycol dimethyl ether (diglyme) in a boiling state has been studied for the first time. Boiling facilitates the cleavage of internal C-O bonds, weakens the cage effect and diglyme regeneration processes, and facilitates the exchange and dimerization reactions of radicals. As compared with radiolysis at room temperature, the amount of unsaturated products of diglyme fragmentation formed during irradiation in the boiling state is smaller by a factor of 4, and the disproportionation products of heavy radicals are found in negligible amounts, if any. The yield of radiolytic decomposition of diglyme under boiling conditions is ∼15 molecule/100 eV, which is higher than that at room temperature by a factor of almost 1.5. [ABSTRACT FROM AUTHOR]

Three ligand-stabilized Mg(BH 4 ) 2 –based complexes have been synthesized and evaluated as potential hydrogen storage media for portable fuel cell applications. The new borohydrides: Mg(BH 4 ) 2 × 0.5Et 2 O and Mg(BH 4 ) 2 × diglyme (diglyme – CH 3 O(CH 2 ) 2 O(CH 2 ) 2 OCH 3 ) have been synthesized and examined by X-ray single crystal diffraction method. Hydrolysis reactions of the compounds liberate hydrogen in quantities ranging from 46 to 96% of the theoretical yield. The hydrolysis of Mg(BH 4 ) 2 and other borohydrides is also accompanied by the diborane formation. The amount of liberated diborane depends on the Mg-coordination environment. To explain this fact quantum-chemical calculations have been performed. It is shown that formation of Mg-O-Mg-bridges enables the side process of diborane generation. It means that the size and denticity of the ligand directly affects the amount of released diborane. In general, the larger the ligand and the higher its denticity, the smaller is amount of diborane produced. The new compound Mg(BH 4 ) 2 × diglyme decomposes without diborane formation that allows one to be considered as a new promising chemical hydrogen storage compound for the practical usage. [ABSTRACT FROM AUTHOR]

Quantitative determination of cellulose content by means of diglyme [bis(2-methoxyethyl) ether] isolation is useful for rapid screening experiments. However, diglyme isolation from softwoods results in a certain amount of residual lignin in the cellulose. In this paper, the lignin content (L) in diglyme cellulose of three pine species (Pinus halepensis Miller, Pinus sylvestris L. and Pinus pinaster Aiton) was analysed by ATR-FTIR spectroscopy and analytical pyrolysis (Py). Py allowed lignin quantification. The influence of wood milling on cellulose yield was also analyzed and it was shown that a particle size between 10 and 60 mesh did not noticeably influence the cellulose yield or L; however, ball-milling to powder did cause a cellulose loss of around 37%. The diglyme method is only reproducible if the experimental parameters are standardized and meticulously followed. [ABSTRACT FROM AUTHOR]

The cointercalation of sodium with the solvent organic molecule diglyme into graphite, forming a ternary graphite intercalation compound ( t -GIC), can resolve the difficulty of making the stage 1 Na-GIC in order to use as a potential anode for Na-ion batteries (NIBs). To clarify the mechanism of such cointercalation, we investigate the atomistic structure, energetics, electrochemical properties, ion and electron conductance, and charge transferring upon the de/intercalation of the solvated Na-diglyme ion into graphite with ab initio calculations. It is found that the t -GICs Na(digl) 2 C n have the lowest negative intercalation energy at n ≈ 21, the Na(digl) 2 complex diffuses relatively fast in the interlayer space, and the electronic conductance can be enhanced upon the cointercalation compared with graphite. The calculations reveal that the diglyme molecule as well as Na atom donates electrons to the graphene layer, indicating an ionic bond between the graphene layer and the diglyme molecule. We belive that this work will contribute to the development of graphite-based anode materials for NIBs. [ABSTRACT FROM AUTHOR]

The compressed liquid densities of binary mixtures of 1-butanol and diethylene glycol dimethyl ether (diglyme) have been measured over the temperature range from (283 to 363) K and at pressures up to 100 MPa covering the whole mole fraction of x1-butanol = (0, 0.3116, 0.5469, 0.7308, 0.8787, 1). The measurements were carried out using a high-pressure vibrating-tube densimeter with the combined expanded uncertainty (k = 2) of 0.6 kg·m-3. The experimental data were correlated using the modified Tait equation with an absolute average percentage deviation lower than 0.015% for each composition of the mixtures. [ABSTRACT FROM AUTHOR]

Converting ‘trash’ waste residua to active functional materials ‘treasure’ with high added value is being regarded as a promising way to achieve the sustainable energy demands. Carbonaceous materials cannot insert sodium except when graphite co-intercalates solvents such as diglyme. Here, we show that petroleum coke and shale coke annealed at different temperatures can also insert sodium by reversible intercalation phenomena in a diglyme-based electrolyte. The structural and morphological studies will reveal significant differences justifying their distinct electrochemical behavior. Galvanostatic tests exhibit a flat plateau at about 0.7 V ascribable to the reversible reaction. At the end of the discharge, a Stage-I ternary intercalation compound is detected. Two diglyme molecules are co-intercalated per alkali ion, as evidenced by 1-D Patterson diagrams, FTIR and TGA analyses. The full sodium-ion cell made with P-2500/NaPF 6 (diglyme)/Na 3 V 2 (PO 4 ) 3 delivered an initial reversible capacity of 75 mA h g −1 at C rate and an average potential of 2.7 V. Thus, the full cell provides an energy density of 202 W h kg −1 . This sodium-ion system can be considered a promising power source that encourages the potential use of low-cost energy storage systems. [ABSTRACT FROM AUTHOR]

Interactions of 1-butyl-3-methylimidazolium cation ([C4mim]+) with bis(trifluoromethanesulfonyl)amide anion ([TFSA]-) and diethyleneglycol dimethyl ether (diglyme) in mixtures of [C4mim][TFSA] ionic liquid and diglyme have been investigated using 1H and 13C NMR spectroscopy and molecular dynamics (MD) simulations. The results of NMR chemical shift measurements and MD simulations showed that the diglyme oxygen atoms have contact with the imidazolium hydrogen atoms of [C4mim]+ in the mixtures. The contact between the hydrogen atoms of imidazolium and the oxygen atoms of [TFSA]- remains even when the diglyme mole fraction (xdiglyme) increases up to 0.9. However, the coordination numbers of the hydrogen atoms of [C4mim]+ with oxygen atoms of diglyme increase with xdiglyme. The [TFSA]- anions around [C4mim]+ are not completely replaced by diglyme even at xdiglyme > 0.9. The MD simulations revealed that the diglymes also have contact with the butyl group of [C4mim]+. The methyl groups of diglyme prefer to have contact with the terminal methyl group of the butyl group, whereas the diglyme oxygen atoms prefer to have contact with the methylene group connected to the imidazolium ring of [C4mim]+. [ABSTRACT FROM AUTHOR]

X-ray scattering data were used to examine the morphological evolution that accompanies the ionomer-to-polyelectrolyte transition. Bulk random ionomer based on methacryl diglyme side chains and sodium sulfonated styrene exhibits an amorphous halo, a backbone correlation peak, and an ionic aggregate spacing peak in X-ray scattering. The ionic peak intensifies as either polymer content or temperature increases due to enhanced aggregation, since the dielectric constant of the polar liquid decreases as temperature is raised. Addition of polar plasticizer into the ionomer softens the ionic interactions by raising the dielectric constant, which weakens the ionic peak, leading to more polyelectrolyte character at higher plasticizer content, with many dissociated Na counterions. There is a wide range of ion content and dielectric constant (gray region in graphic) within which these materials transition from ionomer to polyelectrolyte as the polar plasticizer is added, and both the ionic aggregation peak of the ionomer and the correlation length (interchain spacing) of polyelectrolyte solutions can be resolved. The complete transition to polyelectrolyte occurs when the average distance between the ions becomes larger than the Bjerrum length, so that many Na counterions dissociate, and the ionic aggregate spacing peak disappears. [ABSTRACT FROM AUTHOR]

Electronic structure calculations for late transition metals coordinated by two dithiolene ligands are found to be consistent with existing structures and also predict the geometries of Ni(I) species for which no solid state structures have been reported. Of particular interest are the compounds [M(mnt)2] n− (M = Ni, Pd, and Pt with n = 1, 2, 3; M = Cu with n = 2). Calculations have been performed with and without ion-paring with M(diglyme)+ (M = Li, Na, K) and R4N+ (R = Me, Bu). The diagonal twist angle between two NiS2 planes is found to depend on (i) the metal's d-electron count, spanning from 0° (planar d7 and d8), to 42° (d9), to 90° (pseudo-tetrahedral d10), and (ii) the identity of the ion-paired cations. Calculated ion-pairing energies are functions of the cation size and charge-density, being larger for alkali-metal coordinated diglyme and smaller for tetra-alkyl ammonium cations. © 2016 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Sodium (Na) metal is able to directly use as a battery anode but have a highly reductive ability of unavoidably occurring side reactions with organic electrolytes, resulting in interfacial instability as a primary factor in performance decay. Therefore, building stable Na metal anode is of utmost significance for both identifying the electrochemical performance of laboratory half-cells employed for quantifying samples and securing the success of room-temperature Na metal batteries. In this work, we propose an NaF-rich interface rapidly prepared by pressure and diglyme-induced defluorination reaction for stable Na metal anode. Once the electrolyte is dropped into the coin-type cells followed by a slight squeeze, the Na metal surface immediately forms a protective layer consisting of amorphous carbon and NaF, effectively inhibiting the dendrite growth and dead Na. The resultant Na metal anode exhibits a long-term cycling lifespan over 1800 h even under the area capacity of 3.0 mAh cm -2 . Furthermore, such a universal and facile method is readily applied in daily battery assembly regarding Na metal anode., (© 2023 Wiley-VCH GmbH.)