Solid polymers electrolytes (SPEs) based on sodium bis(fluorosulfonyl) imide (NaFSI) and poly(ethylene oxide) (PEO) with different ether oxygen to sodium (O:Na) molar ratios (n), resulting in ...NaFSI(PEO)n materials are here presented for the first time. These SPEs are extensively compared with the corresponding NaTFSI(PEO)n system in terms of ionic conductivities, thermal properties, and charge carriers – to in detail outline both the role of the different anions used and the salt concentrations employed. While for the most dilute systems (n=20) the two SPE families show similar ionic conductivities in the entire temperature range investigated (273-343K), for n=6 and n=9 they differ significantly; at room temperature, the NaFSI based SPEs show lower ionic conductivities than the NaTFSI based analogues. This difference is mainly ascribed to differences in the morphology; while the NaTFSI salt, possibly by virtue of its large TFSI anion, acts to inhibit crystallization, NaFSI rather seems to favor crystallization. Furthermore, careful Raman spectroscopy analysis of the charge carrier speciation reveal higher aggregates to be present in the most concentrated SPE, NaFSI(PEO)6, and the NaFSI based SPEs in general to result in less “free” anions than the NaTFSI based SPEs. Moreover, as both NaTFSI(PEO)n and NaFSI(PEO)n for n=20 and n=9 exhibit very similar glass transition temperatures, the FSI ion seem to be equally plasticizing as the TFSI ion, but for n=6 the different speciation in terms of charge carriers also affects the relative dynamics of the polymer chains.
The authors review the efforts made from a modeling and simulation perspective in order to assist both the fundamental understanding as well as the development of higher performance sodium‐ion ...battery (SIB) electrolytes. Depending on the type of the electrolyte studied, liquid, ionic liquid, polymer, glass, solid‐state, etc., the simulation methods applied and the research questions in focus differ, but all contribute to more rational progress. Furthermore, the authors create cases of meta‐analysis using literature data. A historical perspective is applied and the focus clearly is on more recent work and novel electrolyte materials. Finally, the authors outline a few prospective areas for where SIB electrolyte simulations can/should be extended for maximum impact in the field.
Modeling and simulations are highly efficient tools to gain a better understanding of the very fundamentals as well as a solid support to the development of higher performance sodium‐ion battery electrolytes. Herein, the authors review liquid, ionic liquid, polymer, glass, and solid‐state electrolytes from a historical perspective, but with a clear focus on the more recent and novel electrolytes.
Al batteries are yet rather unexplored as a promising technology to respond to the growing electrochemical energy storage demands. Despite the outstanding electrochemical activity of ...haloaluminate-based electrolytes, no prospect of practical re-chargeable Al batteries has yet materialized, partly due to these electrolytes' extremely sensitive nature. Hence alternative aluminum conducting electrolytes with sufficient stability are strongly needed. Here a series of room-temperature ternary electrolytes consisting of aluminum trifluoromethanesulfonate (AlTfO sub(3)), N-methylacetamide (NMA), and urea are presented, which provide excellent ionic conductivities by selecting appropriate ratios. Compared to conventional organic electrolytes, unprecedented solvation ability for Al-salts and remarkable ion transport properties were observed. For the optimized composition, AlTfO sub(3)/NMA/urea = 0.05/0.76/0.19, physicochemical properties and vibrational spectroscopy data imply a decoupling of the Al conduction mechanism from viscosity limitations and furthermore that the dissociation state of the AlTfO sub(3) salt drastically changes. These phenomena are likely due to the unique coordination environment of the Al super(3+) ions and the multiple functions of urea in these ternary mixtures. The electrochemical properties of the optimized ternary electrolyte were studied with respect to the electrochemical stability window and using cyclic voltammetry.
Addition of moderate contents (≤20wt%) of ionic liquids (ILs) to binary solid polymer electrolytes (SPEs) is made to alter the overall SPE properties, foremost to increase the room temperature ionic ...conductivity. Sodium conducting ternary electrolytes, based on sodium salts; NaTFSI and NaFSI, the polymer poly(ethylene oxide) (PEO), and pyrrolidinium ILs; Pyr13TFSI and Pyr13FSI, with different compositions: NaX(PEO)n – Pyr13X (X=TFSI, FSI), have been prepared. Raman and dielectric spectroscopy as well as differential scanning calorimetry have been used to evaluate the plasticizing effect of the Pyr13 IL cation and the accompanying TFSI and FSI IL anions via changes in ionic association, crystallinity, polymer chain dynamics, and total ionic conductivity. While all the TFSI based systems seem rather insensitive to the addition of IL with respect to speciation, the situation is much less clear for the FSI based systems. Furthermore, the addition of ILs seems beneficial for inhibiting PEO crystallization, especially for the FSI anion, and also for enhancing the polymer chain dynamics, but yet the FSI based ternary electrolytes show lower ion conductivities as compared to the analogous TFSI based systems.
Abstract
To investigate the pathogenesis of a congenital form of hepatic fibrosis, human hepatic organoids were engineered to express the most common causative mutation for Autosomal Recessive ...Polycystic Kidney Disease (ARPKD). Here we show that these hepatic organoids develop the key features of ARPKD liver pathology (abnormal bile ducts and fibrosis) in only 21 days. The ARPKD mutation increases collagen abundance and thick collagen fiber production in hepatic organoids, which mirrors ARPKD liver tissue pathology. Transcriptomic and other analyses indicate that the ARPKD mutation generates cholangiocytes with increased TGFβ pathway activation, which are actively involved stimulating myofibroblasts to form collagen fibers. There is also an expansion of collagen-producing myofibroblasts with markedly increased PDGFRB protein expression and an activated STAT3 signaling pathway. Moreover, the transcriptome of ARPKD organoid myofibroblasts resemble those present in commonly occurring forms of liver fibrosis. PDGFRB pathway involvement was confirmed by the anti-fibrotic effect observed when ARPKD organoids were treated with PDGFRB inhibitors. Besides providing insight into the pathogenesis of congenital (and possibly acquired) forms of liver fibrosis, ARPKD organoids could also be used to test the anti-fibrotic efficacy of potential anti-fibrotic therapies.
Sodium-ion batteries, the sodium counterpart of the ubiquitous lithium-ion batteries, are currently being developed as a complementary technology to assure resource availability. As battery ...electrolytes tend to be one of the more limiting parts of any battery for both performance and life-length, chemical and physical data on sodium-ion battery electrolytes are important for rational development. Here the cation-anion interaction, a key property of any salt used in an electrolyte, of a number of salts is probed using numerous DFT methods via the ion-pair dissociation reaction: AlkAn ⇌ Alk(+) + An(-), where An(-) is any anion and Alk(+) is Na(+) or Li(+), the latter used here for a straight-forward literature and methodology comparison. Furthermore, the applicability of different DFT functionals for these types of calculations is benchmarked vs. a robust higher accuracy method (G4MP2).
The large electrochemical activities of haloaluminate anions Al n X3n+1−, anionic complexes derived from AlX3 and Lewis basic fertilizers, have significantly contributed to the development of ...industrial coatings and more recently also to electrochemical energy storage. In contrast, cationic metal complexes have just emerged as a class of species interesting as multivalent main charge carriers for Mg, Ca, and especially here Al batteries. Despite the potential of such complexes to efficiently deliver Al3+ cations at the electrode|electrolyte interfaces, very few cationic aluminum complexes that do not contain moisture sensitive Al n X3n+1− counteranions have been reported due to the few, and difficult to synthesize, commercially available parent aluminum salts. Here a range of cationic aluminum complexes with different ligands and anionic structures were successfully synthesized by complexation of AlCl3 with certain ligands to create fully solvated Al(L)6Cl3 complexes and subsequent application of anion metathesis reactions. X-ray crystallography aided by vibrational spectroscopy corroborates the formation of discrete complexes with hexacoordinated octahedral Al3+ cations balanced by three isolated anions. The resulting physicochemical properties are strongly dependent on the constituent ions, and one special choice of ligand and anion results in a novel design of a room temperature quasi-ionic liquid having high ionic conductivity. Although the high-melting complexes with DMSO ligands are inactive, the molten complex exhibits both cathodic and anodic currents. This is the first electrolyte that allows quasi-reversible electrochemical plating/stripping of Al metal without any fragile anion being present.
The solvation structure of several lithium and sodium based electrolytes are explored as a function of salt concentration over a wide range via a detailed PM7 computational study. The cation ...coordination shells are found to be well-defined and solvent rich for dilute electrolytes, while disordered and anion rich for the more concentrated electrolytes. The Na-based electrolytes display larger cation coordination shells with a more pronounced presence of fluorine as compared to the Li-based electrolytes. The origins of the structural differences are discussed as well as their consequences for properties of battery electrolytes and battery usage–especially targeting the current large interest in highly concentrated electrolytes.
Ionic liquid (IL) based sodium-ion (Na+) battery electrolytes obtained by mixing imidazolium-TFSI ILs (EMIm-TFSI and BMIm-TFSI) with the corresponding sodium salt (NaTFSI) have been investigated ...using a wide range of characterization techniques: dielectric spectroscopy, differential scanning calorimetry, densitometry, viscometry, and Raman spectroscopy. The sodium ion conducting electrolytes exhibit excellent ionic conductivities, up to 5.5 mS cm-1 at room temperature, and a useful thermal window of -86 degree C to 150 degree C. In more detail, Raman data analysis supported by DFT calculations on Na+-TFSI complexes, allow us to determine the sodium ion solvation and charge carrier nature as a function of salt concentration. The results are compared to data for the corresponding Li systems and while such electrolytes essentially form Li(TFSI)2- as the main Li+ carrier, the sodium systems seem to dominantly form Na(TFSI)32- complexes. The effects on conductivity and viscosity and the consequences for sodium-ion battery implementation are discussed.
This article explores how learning historical interpretation of Viking-age archaeological artefacts from an intercultural perspective could be facilitated through historical enquiry in primary ...school. Three design principles were formulated for the teaching: (1) enquiry based upon an
authentic intercultural question; (2) enquiry with a focus on source interpretation; and (3) enquiry using material culture in the form of archaeological artefacts. Two questions were addressed: first, how did the teaching design and practice facilitate the intended learning, and second, what
obstacles to learning were encountered as a result of the design? Research data were analysed qualitatively using contentfocused conversation analysis and variation theory. The findings in relation to the first question indicated that the design principles helped teachers facilitate learning
through historical enquiry from an intercultural perspective, and that archaeological artefacts can inspire investigations into history by activating pupils' historical consciousness. The answer to the second question indicated that pupils had difficulties responding to historical enquiries
with synthesized inferences based on historical evidence. A revision of the final phase of the enquiry suggests that focus is on discussing reasonable explanations in relation to artefacts, rather than synthesizing historical inferences based on evidence. This study points to possibilities
of teaching historical interpretation and intercultural perspectives through historical enquiry in primary school, and suggests that archaeological artefacts can be used to initiate historical learning.
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