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Sodium‐ion batteries (SIBs) are promising in several aspects due to their many advantages over lithium‐ion batteries. Among SIB's several outstanding attributes, its low cost, resource abundance, and potential safety make it suitable for large‐scale energy storage systems (ESS). Among the potential cathode materials, poly‐anionic cathode materials could be a better choice for their stability and safety in comparison to layered transition metal oxides and Prussian blue analogues (PBA). However, on the other hand, the conductivity as well as the available capacity of the polyanion compounds are still poor, which limits their applications; moreover, some polyanion cathode operate at low voltage, which reduces the energy density and raises the cost of the battery system. We here try to summarize the recent progress of polyanion compounds as cathode materials for SIB. These compounds are categorized based on the metal redox couple, including V‐, Cr‐, Mn‐, Fe‐, Co‐, and Ni‐polyanion compounds. Our attention is specifically drawn to properties such as reversible redox voltage, capacity, cycling stability, and sodium storage mechanisms. We also discuss the challenges and potential development strategies for the future. [ABSTRACT FROM AUTHOR]

It is a challenging issue to achieve efficient charge transfer between layers for the layered polymer photocatalysts, because the photogenerated carriers would prefer random migration within layers and thus have high reverse recombination rate due to their inherent anisotropy and high exciton binding energy. Herein, an innovative surface grafting strategy is developed to modify the layered polymeric carbon nitride (PCN) making use of phosphotungstic (PWO) polyanions. The surface coupling effect of PWO on PCN effectively improves reduction ability and utility rate of luminous energy through shifting the conduction band (CB) upward and broadening light absorption range to cover near infrared region up to 1000 nm, respectively. In especial, the strong electron-withdrawing effect of surface PWO moieties can reduce layer spacing to shorten electron transfer path and attract the photogenerated electrons transfer from PCN matrix to surface, thus conquering the charge transfer restriction between layers to improve the carrier separation efficiency. As a result, the photocatalytic hydrogen evolution (PHE) performance is dramatically enhanced. The optimal PWO-PCN-1% sample achieves an average PHE rate of 9.6 times that of PCN, stable operation for a total of 28 h on 7 cycles, and an AQY up to 22.3% at 400 nm. This contribution affords a viable modification avenue to overcome the limitation of charge transfer between layers for layered polymer photocatalysts. [Display omitted] • A new surface grafting strategy is developed to modify PCN using PWO polyanions. • The charge transfer restriction between layers is conquered effectively. • The electron-withdrawing effect of PWO moieties improves carrier separation efficiency. • Photocatalytic hydrogen evolution performance is dramatically enhanced. [ABSTRACT FROM AUTHOR]

Digitally‐encoded poly(phosphodiesters) (d‐PPDE) with highly complex primary structures are evaluated for layer‐by‐layer (LbL) assembly. To be easily decoded by mass spectrometry (MS), these digital polymers contain many different monomers: 2 coding units allowing binary encryption, 1 cleavable spacer allowing controlled MS fragmentation, and 3 mass tags allowing fragment identification. These complex heteropolymers are therefore composed of 6 different motifs. Despite this strong sequence heterogeneity, it is found that they enable a highly controlled LbL film formation. For instance, a regular growth is observed when alternating the deposition of negatively‐charged d‐PPDE and positively‐charged poly(allyl amine hydrochloride) (PAH). Yet, in this approach, the interdistance between consecutive coded d‐PPDE layers remains relatively small, which may be an issue for data storage applications, especially for the selective decoding of the stored information. Using poly(sodium 4‐styrene sulfonate) (PSS) as an intermediate non‐coded polyanion, it is shown that a controlled interdistance between d‐PPDE layers can be easily achieved, while still maintaining a regular LbL growth. Last but not least, it is found in this work that d‐PPDE of relatively small molecular weight (i.e., significantly smaller than those of PAH and PSS) still enables a controlled LbL assembly. [ABSTRACT FROM AUTHOR]

Ionogels are emerging as high‐potential pseudosolid electrolytes for lithium‐metal batteries (LMBs), leveraging their intrinsic high ionic conductivity from entrapped ionic liquid (IL) electrolytes. However, their practical application is hindered by poor mechanical strength stemming from the confinement of ILs within a polymer matrix. To address this challenge, the formation of conformal polyion coatings with functional groups is reported to be relevant to LMBs’ application on ionogels, utilizing a layer‐by‐layer (LbL) assembly strategy. This approach significantly enhances the mechanical strength (Young's modulus and tensile strength) and electrochemical performance of ionogels, owing to the tailored interface modifications introduced by functional groups’ specific conformal polyion coatings. The core of this methodology leverages the inherent ionic structure of ionogels to enable facile interface modification through Coulombic interactions between polyanions and polycations. These conformally coated interface functionalized membranes show improved electrochemical performance when integrated with cathode materials such as LiFePO4 (LFP) and LiNi0.8Mn0.1Co0.1O2 (NMC811) in an LMB configuration, underscoring their potential for robust, high‐conductivity, pseudosolid membranes for LMB applications. These innovative pseudosolid membranes offer improved mechanical and electrochemical properties, leading to higher battery efficiency and safety, making them promising candidates for next‐generation LMB technology. [ABSTRACT FROM AUTHOR]

Despite a bicentennial history, the interest in polyiodides and related systems still flourishes. The chemical puzzle provided by the intricate nature of chemical bonding in these polyanions remains challenging these days. The advent of the halogen bond and the spreading interest in supramolecular interactions of halogen-based systems promoted further recent interest. Research in the area of materials, where local bonding details eventually result in desired macroscopic properties, provided a further boost. Herein, we illustrate the consequences of contemplating a different bonding scheme for polyiodides, one making explicit use of electron-deficient multicenter bonds (EDMBs), an emerging concept in this area. We present a reinterpretation of polyiodide bonding using a revised approach to the Lewis dot formulas, leading to a clearer pen-and-paper understanding of their bonding. The model is general and can be applied to other related problems (here polyiodonium cations, and other homo- and hetero-polyhalides). Our alternative narrative has a few interesting consequences on several traditional and currently hot topics, including the nature of basic building blocks for polyiodides, hypervalency vs. hypercoordination, the distinction between covalent bonds and supramolecular interactions, and the nature of secondary and halogen bonds. [ABSTRACT FROM AUTHOR]

Ionic diode‐based generators show great superiority in harvesting low‐frequency mechanical energy from human motions for various wearable applications. The major challenge is to improve their extremely limited output voltage for the miniaturization/simplicity of ionic diode‐based self‐powered devices as well as further improvement of mechanoelectric conversion performance. Herein, the construction of gradient polycation/polyanion heterojunction is demonstrated to vastly boost the output voltage, energy‐harvesting efficiency, and sensing performance of ionic diode. Besides an inherent potential at the polyanion/polycation heterojunction interface, the additional transmembrane potentials can be generated across gradient polyanion and polycation conductors of ionic diodes due to their gradient charge distribution. Consequently, the gradient ionic diode‐based generators produce much higher output voltage (306.53 mV) than previously reported homogeneous ones (4.1–135 mV). Meanwhile, the high output voltage imparts gradient ionic diode‐based generator with ultrahigh power density (50.16 µW cm−2 or 250.8 µW cm−3) and pressure‐perception sensitivity (43582 mV/MPa), which are dramatically increased by 162.76% and 128.71%, respectively, compare to those of homogeneous one. Impressively, the resulting diode‐based generators can generate ultralarge current density (≈0.52 mA cm−2) with ultralong discharge time (>400 s), thus enabling the continuous power generation under the low‐frequency pressure for various wearable and implantable applications. [ABSTRACT FROM AUTHOR]

The aggregation of α-synuclein (α-syn) into amyloid fibrils, a key process in the development of Parkinson's disease (PD) and other synucleinopathies, is influenced by a range of factors such as charged biopolymers, chaperones, and metabolites. However, the specific impacts of different biopolymers on asyn fibril structure are not well understood. In our work, we found that different polyanions and polycations, such as polyphosphate (polyP), polyuridine (polyU), and polyamines (including putrescine, spermidine, and spermine), markedly altered the fibrillation kinetics of γ-syn in vitro. Furthermore, the seeding assay revealed distinct cross-seeding capacities across different biopolymer-induced γ-syn fibrils, suggesting the formation of structurally distinct strains under different conditions. Utilizing cryo-electron microscopy (cryo-EM), we further examined the detailed structural configuration of γ-syn fibrils formed in the presence of these biopolymers. Notably, we found that while polyamines do not change the atomic structure of γ-syn fibrils, polyU and polyP induce the formation of distinct amyloid fibrils, exhibiting a range of structural polymorphs. Our work offers valuable insights into how various charged biopolymers affect the aggregation process and the resultant structures of γ-syn fibrils, thereby enhancing our understanding of the structural variations in α-syn fibrils across different pathological conditions. [ABSTRACT FROM AUTHOR]

Redox flow polymer electrolyte fuel cells (RFFCs) employing heteropolyanions (HPAs) as cathode redox mediators enable continuous power generation through the electrochemical reduction of the HPAs at the carbon cathode and subsequent reoxidation of the reduced-form HPAs in the cathode tank. Currently, effective reoxidation methods are required to achieve both high performance and long-term stability. Heteropolyanions such as α–[PW 12 O 40 ]3– and α–[SiVW 11 O 40 ]5– have increased reoxidation rates in the presence of radical species. In this study, fuel cell performance is investigated by adding Fe3+ and Cu2+ to the aqueous solution of [PV 3 Mo 9 O 40 ]6–, which is used as a catholyte in RFFCs to increase the concentration of radicals in the system. Current–voltage measurements show that the added metal cations in the catholyte increase the power density. A temporary improvement in cell performance is observed during a prolonged current passage test. • Redox flow polymer electrolyte fuel cells employing phosphovanadomolybdate anion as cathode redox mediator. • Adding Fe3+ and Cu2+ to catholyte of redox flow polymer electrolyte fuel cells. • Power density of redox flow polymer electrolyte fuel cells depends on concentration of metal cations. [ABSTRACT FROM AUTHOR]

The stannides SrPdSn (TiNiSi type, orthorhombic space group Pnma) and m-BaPtSn (EuNiGe type, monoclinic space group P21/c) were synthesized from the elements in sealed tantalum ampoules in a high-frequency furnace. Their structures were refined from single-crystal X-ray diffraction data. SrPdSn crystallizes directly from the melt and is stable upon annealing at T = 1073 K. A BaPtSn sample quenched from the melt adopts the cubic LaIrSi-type structure, cubic space group P213 (c-BaPtSn) and shows a temperature induced (annealing at 1070 K) structural phase transition leading to a EuNiGe-type low-temperature modification m-BaPtSn. The phase transition leads to a reconstruction within the polyanionic [PtSn]δ− network. The latter is three-dimensional and composed of ten-membered Pt5Sn5 rings in c-BaPtSn, while the polyanion is two-dimensional in m-BaPtSn and is composed of condensed Pt4Sn4 and Pt2Sn2 rings. The two-dimensional substructure leads to a strong moisture sensitivity for m-BaPtSn. The Pt–Sn distances in both modifications range from 257 to 267 pm, indicating substantial covalent bonding. [ABSTRACT FROM AUTHOR]

Polyanion-based materials are considered one of the most attractive and promising cathode materials for lithium-ion batteries (LIBs) due to their good stability, safety, cost-effectiveness, suitable voltages, and minimal environmental impact. However, these materials suffer from poor rate capability and low-temperature performance owing to limited electronic and ionic conductivity, which restricts their practical applicability. Recent developments, such as coating material particles with carbon or a conductive polymer, crystal deformation through the doping of foreign metal ions, and the production of nanostructured materials, have significantly enhanced the electrochemical performances of these materials. The successful applications of polyanion-based materials, especially in lithium-ion batteries, have been extensively reported. This comprehensive review discusses the current progress in crystal deformation in polyanion-based cathode materials, including phosphates, fluorophosphates, pyrophosphates, borates, silicates, sulfates, fluorosilicates, and oxalates. Therefore, this review provides detailed discussions on their synthesis strategies, electrochemical performance, and the doping of various ions.

Single crystals of CaAl2Pt2, Ca2Al3Pt and Ca2AlPt2 were initially observed in an attempt to synthesize Ca3Al4Pt4. Their structures were determined using single‐crystal X‐ray diffraction experiments. While nominal CaAl2Pt2 (CaBe2Ge2 type, P4/nmm, a=426.79(2), c=988.79(6) pm, wR2=0.0679, 246 F2 values and 18 variables) and Ca2Al3Pt (Mg2Cu3Si type, P63/mmc, a=561.46(5), c=876.94(8) pm, wR2=0.0664, 214 F2 values and 13 variables) exhibit Al/Pt mixing, for Ca2AlPt2 (Ca2Ir2Si type, C2/c, a=981.03(2) b=573.74(1), c=772.95(2) pm, β=101.862(1)° wR2=0.0307, 2246 F2 values and 25 variables) no mixing was observed. Subsequently, the nominal compositions were targeted with synthetic attempts from the elements using arc‐melting and annealing techniques. For CaAl2Pt2 and Ca2Al3Pt always multi‐phase mixtures were observed while Ca2AlPt2 could be obtained as almost X‐ray pure material. Quantum‐chemical calculations were used to investigate the charge transfer in these compounds rendering them polar intermetallics with a designated [AlxPty]δ− polyanion and Caδ+ cations in the cavities of the polyanions. [ABSTRACT FROM AUTHOR]

Polyoxometalates (POMs) are a class of compounds known for the vast range of tunable structures and properties available, leading to applications in areas such as catalysis, energy, and advanced medicine. The ability to covalently functionalize POMs with organic components has been investigated extensively to tune the physical and chemical properties of the resulting hybrid materials. These hybrids, where the organic entity is covalently attached to the POM-core (Class II hybrid POMs) result in a vast library of promising customizable catalytic systems, displaying tunable properties with a high level of synergy between the polyanion and the organic component. A number of Class II hybrids have been investigated for a wide range of catalytic applications, and here, we give a brief overview of Class II hybrids of the p-block elements and their applications in catalysis. [ABSTRACT FROM AUTHOR]

Desolvation processes, though common in self‐assembled biological structures, are rarely evidenced and utilized in the design of crystalline architectures. In this study, we introduce a novel approach using the [Mo8S8O8(OH)8(guest)]2− complex, formed by the self‐condensation of four [MoV2O2S2]2− fragments around a guest unit (MoVIO6H4 or oxalate), as a chaotropic scaffold for crystallizing hybrid organic‐inorganic systems with natural cyclodextrins. Our findings reveal that β‐cyclodextrin (β‐CD) facilitates the formation of host‐guest complexes, while α‐cyclodextrin (α‐CD) induces the formation of a Kagome‐type structure with significant voids. These new compounds were thoroughly characterized using X‐ray diffraction (both powder and single‐crystal), N2 adsorption, elemental and thermogravimetric analysis. Additionally, solution studies using 1H NMR titration and small‐angle X‐ray scattering (SAXS) demonstrated pre‐association of the building units in solution. These results enhance our understanding of the design principles for supramolecular structures composed of inorganic polyanions and cyclodextrins. [ABSTRACT FROM AUTHOR]

A quantitative study of the composition of metastable acidic tungstate-vanadate solutions was carried out. The main polyanions coexisting in the solutions were determined by means of UV spectroscopy. Effect of the initial V: W ratio on the nature and concentration of polyanions was determined. Electrochemical deposition of hydrated tungsten oxide films from mixed solutions was carried out. The addition of 5–30 mol.% of vanadium leads to a significant increase in the deposition rate, and these rates are higher than in analogous solutions with the addition of H2O2. It is shown, that the growth of films in mixed solutions is associated with the formation of the Lindquist polyanions [VW5O19]3− and [V2W4O19]4− with high redox potentials. These polyanions are irreversibly destroyed upon reduction. The influence of various polyanions on the film growth was demonstrated in test experiments on the deposition from solutions prepared from individual salts of the polyanions. Films deposited from mixed tungstate-vanadate solutions contain a very low amount of vanadium as it was shown by elemental analysis. [ABSTRACT FROM AUTHOR]

The layer-by-layer (LbL) assembling of oppositely charged polyelectrolytes was studied using semi-synthetic polysaccharide derivatives, namely the polycations 6-aminoethylamino-6-deoxy cellulose (ADC) and cellulose (2-(ethylamino)ethylcarbamate (CAEC), as well as the polyanion cellulose sulfate (CS). The synthetic polymers poly(allylamine) (PAH) and poly(styrene sulfonate) (PSS) were employed as well for comparison. The stepwise adsorption process was monitored by whispering gallery mode (WGM) experiments and zeta-potential measurements. Distinct differences between synthetic- and polysaccharide-based assemblies were observed in terms of the quantitative adsorption of mass and adsorption kinetics. The LbL-approach was used to prepare µm-sized capsules with the aid of porous and non-porous silica particle templates. The polysaccharide-based capsule showed a switchable permeability that was not observed for the synthetic polymer materials. At ambient pH values of 7, low-molecular dyes could penetrate the capsule wall while no permeation occurred at elevated pH values of 8. Finally, the preparation of protein-loaded LbL-capsules was studied using the combination of CAEC and CS. It was shown that high amounts of protein (streptavidin and ovomucoid) can be encapsulated and that no leaking or disintegration of the cargo macromolecules occurred during the preparation step. Based on this work, potential use in biomedical areas can be concluded, such as the encapsulation of bioactive compounds (e.g., pharmaceutical compounds, antibodies) for drug delivery or sensing purposes. [ABSTRACT FROM AUTHOR]

To understand the phase behaviors of polyelectrolyte solutions, we provide two analytical methods to formulate a molecular equation of state for a system of fully charged polyanions (PAs) and polycations (PCs) in a monomeric neutral component, based on integral equation theories. The mixture is treated in a primitive and restricted manner. The first method utilizes Blum's approach to charged hard spheres, incorporating the chain connectivity contribution by charged spheres via Stell's cavity function method. The second method employs Wertheim's multi-density Ornstein–Zernike treatment of charged hard spheres with Baxter's adhesive potential. The pressures derived from these methods are compared to available molecular dynamics simulations data for a solution of PAs and monomeric counterions as a limiting case. Two-phase equilibrium for the system is calculated using both methods to evaluate the relative strength of phase segregation that leads to complex coacervation. Additionally, the scaling exponents for a selected solution near its critical point are examined. [ABSTRACT FROM AUTHOR]

Natural or synthetic polycations are used in nucleic acid‐based therapies as complexing agents which interact electrostatically with nucleic acids, condense them into nanoparticles, protect them and control their entry into cells. However, although the literature on the formation of nanoparticles known as complexes is well documented, fewer studies have focused on the physical chemistry behind their disassembly, especially under physicochemical conditions found in an intracellular environment. There are several theories of the disassembly of these complexes, one of them consisting in the exchange between the polycations of these particles with biological polyanions. This project is focused on the study of the complexation mechanism of chitosan and calf‐thymus DNA, as well as the stability of the obtained complexes in presence of biological polyanions, i.e., glycosaminoglycans (GAGs). In the presence of polyelectrolyte complexes, GAGs that are present in cells are expected to compete with nucleic acids and dissociate the complex if polycation–GAG association is thermodynamically favored. It is found that chitosan/DNA complexes colloidal stability depends on its [N+]/[P−] charge ratio (R). Furthermore, it is determined that the aggregation onset of the complexes, generated by the addition of different GAGs, depends on the structure and the charge density of the GAGs. [ABSTRACT FROM AUTHOR]

Interfacial instability including the high charge‐transfer resistance and the uncontrolled lithium dendrite growth have severely restricted the safety, fast‐charging, and high‐power capabilities of solid‐state polymeric lithium metal batteries (PLMBs). Here, the study demonstrates the ionic nanoclusters self‐assembled between the lithium ions and a rigid‐rod sulfonated aromatic polyamide Poly 2,2′‐disulfonyl‐4,4′‐benzidine terephthalamide (PBDT) can facilitate uniform lithium deposition; meanwhile, realizing 102–103 times lower interfacial charge‐transfer resistance than PEO‐based electrolytes and excellent lithium dendrite suppression at the interfaces. The cells assembled with this solid‐state polymer electrolyte at room temperature show a record high critical current density (6 mA cm−2/3 mAh cm−2), 80% capacity retention at 10 000 cycles (5 C) with the LiFePO4 cathode. With the temperature increased to 80 °C, the cells enable almost 100% of the theoretical capacity at 3 C and high specific power density (20 kW kg−1). According to the Cryo‐TEM imaging and computational simulation results, it is concluded that these nanoscale self‐assembled ionic nanoclusters play a critical role in realizing the superfast charge‐transfer kinetics by balancing the pre‐exponential factor and activation energy at the lithium‐polymer space‐charge interfaces. This interfacial design strategy based on thermodynamically favored ion‐association and self‐assembly between the metal ions and the polyanions guarantees superior charge‐transfer kinetics in PLMBs. [ABSTRACT FROM AUTHOR]

Sodium‐ion batteries (SIBs) are regarded as next‐generation secondary batteries and complement to lithium‐ion batteries (LIBs) for large‐scale electrochemical energy storage applications due to the abundant availability, even distribution, and cost‐effectiveness of raw sodium resources. The phosphate‐based polyanions stand out of various cathode material owing to their high operation voltage, stable structure, superior safety, and excellent sodium‐storage properties. The undesirable electric conductivities and specific capacities limit their large‐scale industrialization. Herein, a recent research development of phosphate‐based polyanion cathodes including orthophosphate, oxyphosphate, pyrophosphate, and mixed phosphates is thoroughly reviewed. Subsequently, the effect of modification strategies including element doping, surface coating, morphology control, and electrode design toward high‐performance cathode materials for SIBs are systematically explored. Finally, the future research directions of phosphate‐based polyanion cathodes based on electrochemical performance including reversible capacity, voltage, energy density, rate capacity, cycling stability, and commercial applications are comprehensively concluded. It is believed that current review will present instructive perspectives into developing practicable phosphate‐based polyanion cathode materials for SIBs. [ABSTRACT FROM AUTHOR]

Li‐rich antiperovskite (LiRAP) hydroxyhalides are emerging as attractive solid electrolyte (SEs) for all‐solid‐state Li metal batteries (ASSLMBs) due to their low melting point, low cost, and ease of scaling‐up. The incorporation of rotational polyanions can reduce the activation energy and thus improve the Li ion conductivity of SEs. Herein, we propose a ternary rotational polyanion coupling strategy to fasten the Li ion conduction in tetrafluoroborate (BF4−) ion doped LiRAP Li2OHCl. Assisted by first‐principles calculation, powder X‐ray diffraction, solid‐state magnetic resonance and electrochemical impedance spectra, it is confirmed that Li ion transport in BF4− ion doped Li2OHCl is strongly associated with the rotational coupling among OH−, BF4− and Li2−O−H octahedrons, which enhances the Li ion conductivity for more than 1.8 times with the activation energy lowering 0.03 eV. This work provides a new perspective to design high‐performance superionic conductors with multi‐polyanions. [ABSTRACT FROM AUTHOR]

Cellulose is one of the main renewable polymers whose properties are very attractive in many fields, including biomedical applications. The modification of nanocrystalline cellulose (NCC) opens up the possibility of creating nanomaterials with properties of interest as well as combining them with other biomedical polymers. In this work, we proposed the covalent modification of NCC with amphiphilic polyanions such as modified heparin (Hep) and poly(αL-glutamic acid) (PGlu). The modification of NCC should overcome two drawbacks in the production of composite materials based on poly(ε-caprolactone) (PCL), namely, (1) to improve the distribution of modified NCC in the PCL matrix, and (2) to provide the composite material with osteoconductive properties. The obtained specimens of modified NCC were characterized by Fourier-transform infrared spectroscopy and solid-state 13C nuclear magnetic resonance spectroscopy, dynamic and electrophoretic light scattering, as well as thermogravimetric analysis. The morphology of PCL-based composites containing neat or modified NCC as filler was studied by optical and scanning electron microscopy. The mechanical properties of the obtained composites were examined in tensile tests. The homogeneity of filler distribution as well as the mechanical properties of the composites depended on the method of NCC modification and the amount of attached polyanion. In vitro biological evaluation showed improved adhesion of human fetal mesenchymal stem cells (FetMSCs) and human osteoblast-like cells (MG-63 osteosarcoma cell line) to PCL-based composites filled with NCC bearing Hep or PGlu derivatives compared to pure PCL. Furthermore, these composites demonstrated the osteoconductive properties in the experiment on the osteogenic differentiation of FetMSCs. [ABSTRACT FROM AUTHOR]

Recent progress has been made to provide a detailed mechanistic understanding of how extracellular histones promote inflammatory processes. Several therapeutic approaches have been generated in the past years aimed at ameliorating histone tissue deposition or at directly interfering with the proinflammatory effects of extracellular histones. Histone-targeted antibodies, neutralizing peptides, and polyanions have been used successfully in preclinical models of sepsis and cardiovascular inflammation. Extracellular histones instigate an inflammatory triad – centered on cytotoxicity, immune cell stimulation, and coagulation – ultimately shaping the dynamics and outcome of various inflammatory pathologies. Given the virtual absence of beneficial functions of histones in the extracellular space, in recent years a number of interference strategies have emerged. In this review we summarize pathogenic functions of extracellular histones and highlight current developments of therapeutic interference. Finally, we elaborate on the current status of preclinical attempts to interfere with extracellular histones in the context of a focus on sepsis and cardiovascular diseases, both of which are leading causes of mortality worldwide. [ABSTRACT FROM AUTHOR]

Hybrid ns2 metal halides have attracted extensive attention due to the unique photophysical behavior. However, the reasonable improvement of photoluminescence efficiency by accurate structural modulation remains a great challenge. Herein, two kind of antimony halides with formulae as (S)/(R)‐[C6H16N2]3[SbCl5]2·2Cl ((S)/(R)‐1·2Cl) and (S)/(R)‐[C6H16N2]2[SbCl5]2 ((S)/(R)‐2) ([C6H16N2]2+ = 1,2‐Diaminocyclohexane) are developed, in which 0D [Sb4Cl20]8− clusters and 1D infinite [SbCl5]n2n− polyanion chains are adopted, respectively. The stoichiometric tunability enables metastable (S)/(R)‐1·2Cl being transformed to dynamic stable (S)/(R)‐2. All compounds contain a large number of Sb─Cl secondary bonds because of the strong chemical activity of 5s2 electrons. The obtained compounds exhibit broadband orange‐light emission, while photoluminescence quantum yield of (S)/(R)‐2 is significantly enhanced to ≈76% due mainly to the generation of more localized electrons onto 1D chains. Experimental and computational results reveal that efficient broadband emission derives from the synergistic emission of singlet and triplet states, where the presence of shallow trap energy levels leads to anti‐thermal quenching behavior. Furthermore, the highly efficient photoluminescence property allows (S)‐2 to become excellent down‐conversion phosphor for white‐light emitting diode. This work proves that exploring structure‐property relationship in hybrid systems is helpful in promoting the rapid development of high‐performance broadband emission metal halides. [ABSTRACT FROM AUTHOR]

Initiation of the bradykinin generation cascade is responsible for the occurrence of attacks in some types of angioedema without wheals. Hereditary angioedema due to C1 inhibitor deficiency (HAE-C1-INH) is one such clinical entity. In this paper, we explore the existing evidence that mast cells (MCs) degranulation may contribute to the activation of the kallikrein-kinin system cascade, followed by bradykinin formation and angioedema. We present the multidirectional effects of MC-derived heparin and other polyanions on the major components of the kinin-kallikrein system, particularly on the factor XII activation. Although, bradykinin- and histamine-mediated symptoms are distinct clinical phenomena, they share some common features, such as some similar triggers and a predilection to occur at sites where mast cells reside, namely the skin and mucous membranes. In addition, recent observations indicate a high incidence of hypersensitivity reactions associated with MC degranulation in the HAE-C1-INH patient population. However, not all of these can be explained by IgE-dependent mechanisms. Mast cell-related G protein-coupled receptor-X2 (MRGPRX2), which has recently attracted scientific interest, may be involved in the activation of MCs through a different pathway. Therefore, we reviewed MRGPRX2 ligands that HAE-C1-INH patients may be exposed to in their daily lives and that may affect MCs degranulation. We also discussed the known inter-and intra-individual variability in the course of HAE-C1-INH in relation to factors responsible for possible variability in the strength of the response to MRGPRX2 receptor stimulation. The above issues raise several questions for future research. It is not known to what extent a prophylactic or therapeutic intervention targeting the pathways of one mechanism (mast cell degranulation) may affect the other (bradykinin production), or whether the number of mast cells at a specific body site and their reactivity to triggers such as pressure, allergens or MRGPRX2 agonists may influence the occurrence of HAE-C1-INH attacks at that site. [ABSTRACT FROM AUTHOR]

Sodium‐ion batteries (SIBs) have emerged as an attractive alternative for large‐scale energy storage due to their low cost and high safety. The selection of cathode materials, which determine SIB performance, becomes a crucial aspect. Vanadium‐based phosphates are known for their multielectron transfer properties and stable structure, but their intrinsic electronic conductivity is limited. In this regard, bimetallic substitution is an excellent modification method for improving the conductivity property. Herein, a novel Na4VMn0.7Ni0.3(PO4)3@C (NVMNP@C) cathode with less vanadium is designed for SIBs, which exhibits outstanding electrochemical performance at 25 °C, delivering rate capacity of 67 mA h g−1 at 3 A g−1, and long‐term cyclability of remaining 74.6% after 4800 cycles at 2 A g−1. Furthermore, excellent low‐temperature adaptability (82 mA h g−1 at 20 mA g−1, 60 mA h g−1 at 400 mA g−1, and 90.4% capacity retention after 230 cycles at 100 mA g−1) at −40 °C is also achieved. This unique work has broken a feasible pathway for high‐performance SIB cathode at low temperature. [ABSTRACT FROM AUTHOR]

A study was carried out on the quality of the cobalt carbonate raw material and heat treatment conditions on the activity of Co-Mo and Ni-Mo hydrotreating catalysts for a mixed diesel fraction. The relevant properties of the impregnation solution are the purity of the cobalt carbonate starting material and the synthesis temperature. A Raman spectroscopic method was proposed for monitoring the cobalt carbonate quality. Heat treatment of the catalyst was found to affect its activity. The optimal ultimate calcination temperatures for the Co-Mo and Ni-Mo catalysts were found to be very different. [ABSTRACT FROM AUTHOR]

Postoperative abdominal adhesions are a common clinical problem after surgery and can cause many serious complications. Current most commonly used antiadhesion products are less effective due to their short residence time and focus primary on barrier function. Herein, we developed a sprayable hydrogel barrier (sHA-ADH/OHA-E) with self-regulated drug release based on ROS levels at the trauma site, to serve as a smart inflammatory microenvironment modulator and GATA6+ macrophages trap for non-adherent recovery from abdominal surgery. Sulfonated hyaluronic acid (HA) conjugates modified with adipic dihydrazide (sHA-ADH), and oxidized HA conjugates grafted with epigallocatechin-3-gallate (EGCG) via ROS-cleavable boronate bonds (OHA-E) were synthesized. sHA-ADH/OHA-E hydrogel was facilely fabricated within 5 s after simply mixing sHA-ADH and OHA-E through forming dynamic covalent acylhydrazones. With good biocompatibility, appropriate mechanical strength, tunable shear-thinning, self-healing, asymmetric adhesion, and reasonable in vivo retention time, sHA-ADH/OHA-E hydrogel meets the requirements of a perfect physical barrier. Intriguingly, sulfonic acid groups endowed the hydrogel with satisfactory anti-fibroblast and macrophage attachment capability, and were demonstrated for the first time to act as polyanion traps to prevent GATA6+ macrophages aggregation. Importantly, EGCG could be intelligently released by ROS triggering to alleviate oxidative stress and promote proinflammatory M1 macrophage polarize to antiinflammatory M2 phenotype. Further, the fibrinolytic system balance was restored to reduce fibrosis. Thanks to the above advantages, the sHA-ADH/OHA-E hydrogel exhibited excellent anti-adhesion effects in a rat sidewall defect–cecum abrasion model and is expected to be a promising and clinically translatable antiadhesion barrier. [Display omitted] • The ROS-responsive hydrogel scavenges ROS and inhibits macrophage aggregation. • EGCG can be released by ROS triggering to relief oxidative stress and inflammatory. • The hydrogel acts as a perfect physical barrier and a smart inflammatory modulator. • The hydrogel reduces adhesion formation by regulating its pathological process. [ABSTRACT FROM AUTHOR]

Chitosan is a natural cationic polysaccharide that could form bonds with negatively charged polyanions like sodium tripolyphosphate (STPP) as a crosslinker. One of the important factors to develop nanoparticles is the concentration of polymer. The increased polymer concentration will increase the viscosity of the solution formed, and the size of the nanoparticles created will increase. However, if the amount of polymer is too small, the particles formed are smaller, and aggregation could be formed. In this study, the ethanolic extract of bay leaf (Syzygium polyanthum) was used as a drug that has a potent antidyslipidemia effect by lowering cholesterol and triglyceride levels. Studies on the ethanolic extract of a bay leaf as an anti-dyslipidemia are still limited. The objective of this research was an investigate effect of the chitosan concentration used 0.6 mg/ml (F1); 1mg/ml (F2); and 1.4 mg/ml (F3) on the physical characteristics of ethanolic extract of bay leaf (Syzygium polyanthum) nanoparticles (NSPs) prepared by cross-linking methods. The result of particle size evaluation showed that the particle size was 665.1 nm ± 14.71 (F1); 180.1 nm ± 0.5; and 221.35 nm ± 1.91 (F3), while the polydispersity index F1, F2, and F3 were 0.773 ± 0.152; 0.220 ± 0.016; and 0.212 ± 0.024 respectively. The results of this study found F2 was the most optimal chitosan concentration with particle size under 200 nm, and polydispersity index under 0.5 with positive ζ-potential value. In conclusion, chitosan concentration showed has an effect on the physical characteristics of the nanoparticles. [ABSTRACT FROM AUTHOR]

A series of proof-of-concept models of polyoxomolybdates with different protonated disubstituted aniline counterions and the same β-Mo8O26 polyanion were synthesized to study the mechanism governing the formation of the intermolecular charge transfer (inter-CT) band. [ABSTRACT FROM AUTHOR]

Polyphosphate (polyP) synthesis is a ubiquitous stress and starvation response in bacteria. In diverse species, mutants unable to make polyP have a wide variety of physiological defects, but the mechanisms by which this simple polyanion exerts its effects remain unclear. One possibility is that polyP's many functions stem from global effects on the biophysical properties of the cell. We characterize the effect of polyphosphate on cytoplasmic mobility under nitrogen-starvation conditions in the opportunistic pathogen Pseudomonas aeruginosa. Using fluorescence microscopy and particle tracking, we quantify the motion of chromosomal loci and cytoplasmic tracer particles. In the absence of polyP and upon starvation, we observe a 2- to 10- fold increase in mean cytoplasmic diffusivity. Tracer particles reveal that polyP also modulates the partitioning between a "more mobile" and a "less mobile" population: Small particles in cells unable to make polyP are more likely to be "mobile" and explore more of the cytoplasm, particularly during starvation. Concomitant with this larger freedom of motion in polyP-deficient cells, we observe decompaction of the nucleoid and an increase in the steady-state concentration of ATP. The dramatic polyP-dependent effects we observe on cytoplasmic transport properties occur under nitrogen starvation, but not carbon starvation, suggesting that polyP may have distinct functions under different types of starvation. [ABSTRACT FROM AUTHOR]

Uncontrolled transport of anions leads to many issues, including concentration polarization, excessive interface side reactions, and space charge-induced lithium dendrites at the anode/electrolyte interface, which severely deteriorates the cycling stability of lithium metal batteries. Herein, an asymmetrical polymer electrolyte modified by a boron-containing single-ion conductor (LiPVAOB), is designed to inhibit the nonuniform aggregation of free anions in the vicinity of the lithium anode through the repulsion effect improving the lithium-ion transference number to 0.63. This LiPVAOB exerts a repulsion interaction with free anions even at a long distance and a selective effect for free anions transport, which diminishes uneven aggregation of free anions at the interface and suppresses space charges-induced lithium dendrites growth. Consequently, the assembled Li||Li cell delivers an ultra-long cycle for over 5400 h. The Li||LiFePO4 cell exhibits outstanding cycle performance with a capacity retention of 93% over 4500 cycles. In particular, the assembled high-voltage Li||Li1.2Ni0.2Mn0.6O2 cell (charged to 4.8 V) exhibits good cycle stability with a high specific capacity of 245 mAh g-1. This designed polymer electrolyte provides a promising strategy for regulating ion transport to inhibit space charge-induced lithium dendrite growth for high-performance lithium metal batteries. [ABSTRACT FROM AUTHOR]

Polypyrrole is a popular conjugated polymer that becomes highly conductive in its p-doped state. The intrinsically non-polar nature of the conjugated bond network limits the processing options of such polymers. Surfactants and polyanions help increase dispersity of conductive polymer in suitable solvents for processing. However, while such dispersions can be highly stable, they are formed by complex nanostructures that significantly impact the conducting polymer composite's bulk properties. Similarly, complex nanostructures can be formed when surfactants or polyelectrolytes serve as templates during the polymerization of the conducting polymer precursor. Following the report of polypyrrole:carboxymethyl cellulose composites in battery electrodes as conductive binders, we are here investigating the role that nanostructure control can have in optimizing their performance. Using methyl orange as a structural template, we can control the composite's nanoscopic shape between nanospheres and nanofibers. In the bulk material, the latter gives rise to significantly increased electronic conductivity and capacitance in battery use conditions, underlining the opportunities for improved performance of conducting polymer composites by controlling synthesis conditions. [ABSTRACT FROM AUTHOR]

Polyelectrolyte solutions are of considerable scientific and practical importance. One of the most widely studied polymer is polystyrene sulfonate (PSS), which has a hydrophobic backbone with pendant charged groups. A polycation with similar chemical structure is poly(vinyl benzyltri methyl) ammonium (PVBTMA). In this work, we develop coarse-grained (CG) models for PSS and PVBTMA with explicit CG water and with sodium and chloride counterions, respectively. We benchmark the CG models via a comparison with atomistic simulations for single chains. We find that the choice of the topology and the partial charge distribution of the CG model, both play a crucial role in the ability of the CG model to reproduce results from atomistic simulations. There are dramatic consequences, e.g., collapse of polyions, with injudicious choices of the local charge distribution. The polyanions and polycations exhibit a similar conformational and dynamical behavior, suggesting that the sign of the polyion charge does not play a significant role. [ABSTRACT FROM AUTHOR]

A wheel-shaped Zr-substituted phosphotungstate, [N(CH3)4]2K16Na10.5H10.5[{Zr(C2O4)2}3(PO4)(P6W39O150)]·45H2O (1), was synthesised from a hexavacant Dawson-type precursor [H2P2W12O48]12−via a conventional solution method. Compound 1 features a wheel-shaped polyanion comprising an annular [P6W39O150]36− cluster supported by a turbine-shaped [{Zr(C2O4)2}3(PO4)]3− fragment, with three oxalate groups covalently anchored to W atoms. Compound 1 was systematically characterized by IR, UV, PXRD, TGA and 31P NMR spectra. The 31P NMR spectra over time were monitored to verify the stability of 1 in aqueous solution. This compound possesses remarkable proton conductive behavior with a high conductivity of 1.18 × 10−2 S cm−1 at 368 K. [ABSTRACT FROM AUTHOR]

In fluorides, the M4+ cations of M = Ti, V, Cr, Mn, Ge, Sn, and Pb favour the octahedral coordination of six F ligands. Some examples of M4+ with larger cations (M = Zr, Hf, W) in octahedral coordination are also known. If not enough F ligands are available to have isolated MIVF6 octahedra, they must share their F ligands. The crystal structures of such fluoride metalates (IV) show the variety of possible structural motifs of the zero-dimensional oligomeric anions [M2F11]3− (M = Ti, Cr), [M3F15]3− (M = Zr, Hf), [M3F16]4− (M = Ge), [M4F18]2− (M = Ti, W), [M4F19]3− (M = Ti), [M4F20]4− (M = Ti), [M5F23]3− (M = Ti), [M6F27]3− (M = Ti), [M6F28]4− (M = Ti), [M8F36]4− (M = Ti, Mn), [M10F45]5− (M = Ti) to one-dimensional chains ([MF5]−)∞ (M = V, Ti, Cr, Ge, Sn, Pb), double chains ([M2F9]−)∞ (M = Ti, Mn), columns ([M3F13]−)∞ (M = Ti), ([M4F19]3−)∞ (M = Ti), ([M7F30]2−)∞ (M = Ti), ([M9F38]2−)∞) (M = Ti), two-dimensional layers ([M2F9]−)∞ (M = Cr), ([M8F33]−)∞ (M = Ti), and three-dimensional ([M6F27]3−)∞ (M = Ti) architectures. A discrete monomeric [M2F9]− anion with two MIVF6 octahedra sharing a common face has not yet been experimentally demonstrated, while two examples containing discrete dimeric [M2F10]2− anions (M = Ti) with two MIVF6 octahedra sharing an edge are still in question. [ABSTRACT FROM AUTHOR]

Rapid advances in nucleic acid therapies highlight the immense therapeutic potential of genetic therapeutics. Lipid nanoparticles (LNPs) are highly potent nonviral transfection agents that can encapsulate and deliver various nucleic acid therapeutics, including but not limited to messenger RNA (mRNA), silencing RNA (siRNA), and plasmid DNA (pDNA). However, a major challenge of targeted LNP-mediated systemic delivery is the nanoparticles' nonspecific uptake by the liver and the mononuclear phagocytic system, due partly to the adsorption of endogenous serum proteins onto LNP surfaces. Tunable LNP surface chemistries may enable efficacious delivery across a range of organs and cell types. Here, we describe a method to electrostatically adsorb bioactive polyelectrolytes onto LNPs to create layered LNPs (LLNPs). LNP cores varying in nucleic acid cargo and component lipids were stably layered with four biologically relevant polyanions: hyaluronate (HA), poly-L-aspartate (PLD), poly-L-glutamate (PLE), and polyacrylate (PAA). We further investigated the impact of the four surface polyanions on the transfection and uptake of mRNA- and pDNA-loaded LNPs in cell cultures. PLD- and PLE-LLNPs increased mRNA transfection twofold over unlayered LNPs in immune cells. HA-LLNPs increased pDNA transfection rates by more than twofold in epithelial and immune cells. In a healthy C57BL/6 murine model, PLE- and HA-LLNPs increased transfection by 1.8-fold to 2.5-fold over unlayered LNPs in the liver and spleen. These results suggest that LbL assembly is a generalizable, highly tunable platform to modify the targeting specificity, stability, and transfection efficacy of LNPs, as well as incorporate other charged targeting and therapeutic molecules into these systems. [ABSTRACT FROM AUTHOR]

Polymeric multilayer films were prepared using a layer-by-layer (LBL) technique on glass surfaces, by repeated and sequential dipping into dilute aqueous solutions of various combinations of water-soluble polyanions (polyacrylic acid (PAA)), polycations (polyallylamine hydrochloride (PAH) or chitosan (CS)), with bi-functional water-soluble cationic azo dyes bismark brown R bismarck brown red or bismark brown Y (BBY), or anionic azo dyes allura red (ALR) or amaranth (AMA), as ionic cross-linkers. The electrostatically-assembled ionically-paired films showed good long-term stability to dissolution, with no re-solubility in water. However, upon exposure to low power visible light under running water, the films photo-disassembled back to their water-soluble constituent components, via structural photo-isomerization of the azo ionic crosslinkers. The relative rate of the disassembly (RRD) of the films was established using UVVis spectroscopy, demonstrating that these assemblies can in principle represent fully recyclable, environmentally structurally degradable materials triggered by exposure to sunlight, with full recovery of starting components. A density functional theory treatment of the allura red azo dye rationalizes the geometrical isomerization mechanism of the photo-disassembly and provides insight into the energetics of the optically-induced structural changes that trigger the disassembly and recovery. [ABSTRACT FROM AUTHOR]

Owing to their rich structural chemistry and unique electrochemical properties, vanadium-based materials, especially the low-dimensional ones, are showing promising applications in energy storage and conversion. In this invited review, low-dimensional vanadium-based materials (including 0D, 1D, and 2D nanostructures of vanadium-containing oxides, polyanions, and mixed-polyanions) and their emerging applications in advanced alkali-metal-ion batteries (e.g., Li-ion, Na-ion, and K-ion batteries) are systematically summarized. Future development trends, challenges, solutions, and perspectives are discussed and proposed. Mechanisms and new insights are also given for the development of advanced vanadium-based materials in high-performance energy storage and conversion. [ABSTRACT FROM AUTHOR]

Characterization of zein aqueous solutions, as a function of the ethanol content and pH, was performed, giving information on the zein aggregation state for the construction of complexes. The aggregation state and surface charge of zein was found to depend on the mixed solvent composition and pH. Nonstoichiometric complex nanoparticles (NPECs) were prepared by electrostatically self-assembling zein, as the polycation, and sodium alginate or chondroitin sulfate, as the polyanions, at a pH of 4. A wide range of parameters were investigated: the alcohol–water content in the zein solutions, the charge molar ratios, the solution addition order and the addition rate. The resulting nanoparticles were characterized by dynamic and electrophoretic light scattering, circular dichroism and scanning electron microscopy. The smallest size for the NPECs (100 nm) was obtained when the polysaccharides acted as the titrate with an addition rate of 0.03 mL·min−1. The NPECs with the best characteristics were selected for loading with ciprofloxacin and then deposited on a cellulosic material in order to evaluate their antibacterial activity. Substantial drug encapsulation with desired drug release profiles were found together with notable antibacterial efficiency, showing the tunability of the properties for both the zein and its complexes with polysaccharides, together with their application potential in the biomedical field. [ABSTRACT FROM AUTHOR]

Although the electrochemical properties of various cathode candidates for sodium‐ion batteries (SIBs) are intensively studied on the material level, the evaluation and comparison from the perspective of future practical implementation are still lacking. In particular, air stability, which is often overlooked, will not only affect the electrode manufacturing processes but also cause detrimental structural change. Herein, two recently commercialized cathode products of NaNi1/3Fe1/3Mn1/3O2 (NFM) and Na3V2(PO4)3 (NVP) are adopted to evaluate their stability in ambient atmospheres and investigate the structural degradation mechanisms. Theoretical calculations and experimental results demonstrate that the stability of NFM is significantly inferior to that of NVP during air exposure owing to the thermodynamically preferred chemical transformation of NFM. Furthermore, Raman mapping and X‐ray diffraction (XRD) measurements reveal the generation of alkaline, which accelerates the structural degradation of NFM. Accordingly, a simple second‐sintering strategy is proposed to enhance the air stability of NFM by removing impurities and retrieving surface‐precipitated Na+ into the crystalline host. In situ XRD reveals the stabilized crystal structure after the second‐sintering treatment not only effectively inhibits the chemical transformation of NFM in air but also endows the improved cycling stability (a high capacity retention of 90.7% after 200 cycles). [ABSTRACT FROM AUTHOR]

A H15P3V6Mo18O84 aqueous solution containing phosphovanadomolybdate anions such as [PV3Mo9O40]6− and [PV2Mo10O40]5− were applied to a catholyte of redox flow polymer electrolyte fuel cells (PEFCs). This system enables continuous power generation by the electrochemical reduction of the phosphovanadomolybdate anions over the carbon cathode and subsequent reoxidation of the reduced phosphovanadomolybdate anions in the cathode tank. Currently, investigations on H15P3V6Mo18O84 aqueous solution have been limited to compositional analysis only, and there are no reports of its application to the catholyte. In this study, the performance of H15P3V6Mo18O84 aqueous solution using as the catholyte in redox flow PEFCs was investigated. In addition, the pH of catholytes was increased, and effects on the performance were compared. Current–voltage measurements showed that increasing the pH (0.3 → 2.5) decreased the power density (42 mW cm−2 → 17 mW cm−2). On the other hand, the reduction–reoxidation operation showed that increasing the pH increased the reoxidation rate of the phosphovanadomolybdate anions (0.5 mmol min−1 → 2.2 mmol min−1). This study is the first step toward the use of H15P3V6Mo18O84 aqueous solution as a catholyte in redox flow PEFCs.

The synthesis of poly(styrene sulfonate) with hydrolysable ester groups in the main chain is reported. The material is obtained by free radical copolymerization of either styrene sulfonate sodium salt (SSNa) or styrene sulfonate alkyl esters (SSA) with the cyclic ketene acetal 2‐methylen‐1,3,6‐trioxocane (MTC). As for other systems made from cyclic ketene acetals, the reactions are difficult to control and give copolymers with high polydispersity index. MTC homopolymer is obtained as a side product in both cases. Thermal cleavage of the alkyl protective groups of the poly(styrene sulfonate alkyl esters) to obtain the target polystyrene sulfonate anions remains incomplete. Thus, direct synthesis of the polyanion from SSNa and MTC is the more efficient process, especially since the poly(SSNa‐co‐MTC) copolymer can be easily separated from MTC homopolymer. 1H‐NMR analytics indicates MTC repeat unit contents of 2–11%, depending on the initial SSNa to MTC ratio. The MTC ester groups of the copolymers are hydrolyzed in aqueous conditions, with and without enzyme, and a marked decrease in the molar mass is observed after hydrolysis. This confirms that these copolymers have the designed intended break points in the main chain, and could become a part of fully degradable electroactive polymer systems. [ABSTRACT FROM AUTHOR]

In aqueous solutions, cetyltrimethylammonium cations bind to carrageenan polyanions, and the resulting ionic associates form macroscopic aggregates due to hydrophobic interaction. At certain ratios of cetyltrimethylammonium to carrageenan, the resulting colloidal particles auto-flocculate. According to visual observations, the ratio ranges from 1 to 3 mmol/g; otherwise the suspensions are stable. By measuring the sedimentation rate and particle size distribution, the most extensive flocculation was found to be from 1.7 to 2.3 mmol/g. The ratio corresponding to the fastest auto-flocculation was precisely determined by titrating the reagents with small increments and recording the turbidity. The turbidimetric titration plots contain distinct break points corresponding to the most extensive flocculation. These break points occur at the same ratio of carrageenan to cetyltrimethylammonium over a wide range of reagent concentrations. The precise values of the critical ratio were found to be 1.78 and 1.53 mmol/g, respectively, during the titration of cetyltrimethylammonium with carrageenan and vice versa. The number of anionic sulfate groups in carrageenan was measured by ICP OES and found to be 1.35 mmol/g. This value is consistent with the critical ratio of the auto-flocculation. [ABSTRACT FROM AUTHOR]

New solid compounds A3−xGaO4H1−y (A = Sr, Ba; x ∼0.15, y ∼0.3), which are the first oxyhydrides containing gallium ions, have been synthesized by high-pressure synthesis. Powder X-ray and neutron diffraction experiments revealed that the series adopts an anti-perovskite structure consisting of hydride-anion-centered HA6 octahedra with tetrahedral GaO4 polyanions, wherein the A- and H-sites show partial defect. Formation energy calculations from the raw materials support that stoichiometric Ba3GaO4H is thermodynamically stable with a wide band gap. Annealing the A = Ba powder under flowing Ar and O2 gas suggests topochemical H− desorption and O2−/H− exchange reactions, respectively. [ABSTRACT FROM AUTHOR]

A two-dimensional supramolecular framework with a tetragonal structure is constructed via host–guest interaction of a pillar[5]arene grafted polyanion with a modified porphyrin. The membrane of the framework with a chiral counterion exhibits enantiomeric selectivity during the filtration of racemic molecules with amino groups, demonstrating broadened potential in chiral separations. [ABSTRACT FROM AUTHOR]

Binary phases of triel (Tr) and pentel (Pn) elements (III‐V semiconductors) represent a unique compound class due to their tunable intrinsic band gap in dependency of the element combination. We report here on two new compounds in the ternary system K−In−As. In K3InAs2 the edge‐sharing tetrahedral InAs4 units are connected via opposed edges of the tetrahedra forming linear [InAs2]3− chains and are thus iso(valence)‐ electronic with SiS2. In K7In4As6, the InAs4 tetrahedra are connected via neighboring edges of the tetrahedra forming zig‐zag chains. These chains are linked in two directions through dimeric [As3In−InAs3] units. Both reported Zintl phases extend the number of structures that possess the same In−As ratio. In K3InAs2 a one‐dimensional polyanion in contrast to known Na3InAs2 comprising a three‐dimensional polyanion structure is found. K7In4As6 forms together with the known phases K2In2As3 and K3In2As3 a series of Zintl phases with the ratio In : As=2 : 3. Even though the three phases differ only slightly in their valence electron concentration (VEC) of the polyanion, the VECs have a strong influence on the structures. Syntheses, crystal structures and the electronic band structures are reported. The compounds are discussed in the context of the Zintl concept. [ABSTRACT FROM AUTHOR]

Single‐ion conductive polymer electrolytes (SICPEs) with a cationic transference number (tLi+) close to unity exhibit specific advantages in solid‐state batteries (SSBs), including mitigating the ion concentration gradient and derived problems, suppressing the growth of lithium dendrites, and improving the utilization of cathode materials and the rate performance of SSBs. However, the application of SICPEs remains major challenges, i.e., the ionic conductivity is inferior at room temperature. Therefore, the recent accomplishments in improving the ambient ionic conductivity to be compatible SICPEs with a high transference number are discussed in this review. In particular, some strategies of delocalizing charges in polyanions, designing a highly conductive polymer matrix, and utilizing synergistic effects in SICPEs are focused to shed light on the further development of solid polymer electrolytes for SSBs. Finally, multifunctional species of SICPEs are discussed in view of the mechanical contact and/or charge transfer problems at the solid–solid interface in SSBs. [ABSTRACT FROM AUTHOR]

Complex coacervation describes the liquid‐liquid phase separation of oppositely charged polymers. Active coacervates are droplets in which one of the electrolyte's affinity is regulated by chemical reactions. These droplets are particularly interesting because they are tightly regulated by reaction kinetics. For example, they serve as a model for membraneless organelles that are also often regulated by biochemical transformations such as post‐translational modifications. They are also a great protocell model or could be used to synthesize life–they spontaneously emerge in response to reagents, compete, and decay when all nutrients have been consumed. However, the role of the unreactive building blocks, e.g. the polymeric compounds, is poorly understood. Here, we show the important role of the chemically innocent, unreactive polyanion of our chemically fueled coacervation droplets. We show that the polyanion drastically influences the resulting droplets′ life cycle without influencing the chemical reaction cycle–either they are very dynamic or have a delayed dissolution. Additionally, we derive a mechanistic understanding of our observations and show how additives and rational polymer design help to create the desired coacervate emulsion life cycles. [ABSTRACT FROM AUTHOR]

Komplexe Koazervation beschreibt die Flüssig‐Flüssig‐Phasentrennung entgegengesetzt geladener Polymere. Aktive Koazervate sind Tröpfchen, in denen die Affinität eines der Elektrolyte durch chemische Reaktionen gesteuert wird. Diese Tröpfchen sind besonders interessant, weil ihre Eigenschaften durch die Reaktionskinetik streng reguliert werden. Sie dienen beispielsweise als Modell für membranlose Organellen, die häufig auch durch biochemische Transformationen, wie z. B. posttranslationale Modifikationen, gesteuert werden. Sie sind auch ein gutes Modell für Protozellen oder könnten zur Synthese von künstlichem Leben verwendet werden – sie entstehen spontan als Reaktion auf Reagenzien, konkurrieren und zerfallen, sobald alle Nährstoffe verbraucht sind. Allerdings ist die Rolle der unreaktiven Bausteine, z. B. der Polymere, bisher kaum verstanden. Mit unserer Arbeit zeigen wir die wichtige Rolle des unreaktiven Polyanions unserer chemisch betriebenen Koazervattropfen. Wir zeigen, dass das Polyanion den Lebenszyklus der resultierenden Tröpfchen drastisch beeinflusst, ohne den chemischen Reaktionszyklus selbst zu beeinflussen – entweder sind sie sehr dynamisch oder lösen sich nur verzögert auf. Darüber hinaus leiten wir den Mechanismus dahinter ab und zeigen, wie Additive und rationales Polymerdesign dazu beitragen können, die gewünschten Lebenszyklen von Koazervatemulsionen zu erzeugen. [ABSTRACT FROM AUTHOR]