High Ion Research Articles

Copper silicate nanoneedle arrays on reduced graphene oxide like “shelter forest” guiding Zn gradient deposition

With the sustainable and efficient development of aqueous zinc ion batteries (AZIBs), the research on addressing the issues of the adaptability and durability of zinc anodes has been hot-topic and is still of great challenge. In this work, inspired by the sand treatment and afforestation of the Gobi Beach in Northwest China to ameliorate the problem of wind and sand encroachment, we propose a material with a morphology similar to that of a “shelter forest”, CuSiO3 nanoneedles arrays grown on both sides of reduced graphene oxide (rGO@CuSi), as a coating layer on the zinc metal surface to guide Zn gradient deposition. The presence of rGO improves the electrical conductivity of CuSiO3, and the finite element simulation of the electric field and Zn2+ concentration proves that the electric field distribution can be effectively homogenized and the local current density can be reduced for the rGO@CuSi-Zn electrode with the surface presenting the shape of a protective forest. This is due to the abundant pores between the nano-needle array structures on the surface of the electrode, which provides high electron and ion transport paths, and are conducive to achieve uniform Zn deposition, like the principle of wind-sand stabilization by protective forest. Both electrochemical experiments and density functional theory calculations show that the negatively charged surface of rGO@CuSi with good Zn affinity is more capable of guiding Zn2+ transport. Thanks to its inherent material and structural characteristics, the rGO@CuSi-Zn anode has a high specific capacity and good cycling stability. This study provides an insight for interface engineering like protective forest to accelerate the commercialization of high-performance Zn-based batteries.

A new highly active and CO2-stable heterostructure cathode material for solid oxide fuel cells developed from bismuth ion-modified cation-deficient Nd0.9BaCo2O5+δ

Efficient oxygen reduction kinetics as well as excellent stability are the main goals of current electrode materials for solid oxide fuel cells (SOFCs). Here, we present the latest findings regarding the augmentation of performance in SOFC through utilization of a novel heterogeneous cathode, consisting of an excess cation-deficient double perovskite Nd0.9BaCo2O5+δ (NBC90) backbone and in situ exsolved BaCo1-yBiyO3-x nanoparticles modified by bismuth (NBC90+B). The anisotropic growth of such self-assembled nanoparticles and the formation of multiple heterointerfaces exhibit an extremely strong activation effect. The in situ formed BaCo1-yBiyO3-x nanoparticles and cation-deficient NBC90 parental perovskite significantly enhance the catalytic activity and durability of the cathode toward oxygen reduction. The structural stability and CO2 tolerance of the cathode are greatly enhanced, which is attributed to the penetration of the high acidic Bi ions in the separated phase and the synergistic effect of the two-phase interface. The results unequivocally demonstrate the exceptional stability and efficiency of the NBC90+B composite as a promising cathode candidate for SOFCs.

Improvement of Tumor Neoantigen Detection by High-Field Asymmetric Waveform Ion Mobility Mass Spectrometry.

Cancer neoantigens have been shown to elicit cancer-specific T-cell responses and have garnered much attention for their roles in both spontaneous and therapeutically induced antitumor responses. Mass spectrometry (MS) profiling of tumor immunopeptidomes has been used, in part, to identify MHC-bound mutant neoantigen ligands. However, under standard conditions, MS-based detection of such rare but clinically relevant neoantigens is relatively insensitive, requiring 300 million cells or more. Here, to quantitatively define the minimum detectable amounts of therapeutically relevant MHC-I and MHC-II neoantigen peptides, we analyzed different dilutions of immunopeptidomes isolated from the well-characterized T3 mouse methylcholanthrene (MCA)-induced cell line by MS. Using either data-dependent acquisition or parallel reaction monitoring (PRM), we established the minimum amount of material required to detect the major T3 neoantigens in the presence or absence of high field asymmetric waveform ion mobility spectrometry (FAIMS). This analysis yielded a 14-fold enhancement of sensitivity in detecting the major T3 MHC-I neoantigen (mLama4) with FAIMS-PRM compared with PRM without FAIMS, allowing ex vivo detection of this neoantigen from an individual 100 mg T3 tumor. These findings were then extended to two other independent MCA-sarcoma lines (1956 and F244). This study demonstrates that FAIMS substantially increases the sensitivity of MS-based characterization of validated neoantigens from tumors.

All solid-state lithium-ion batteries based on designed polyrotaxane-containing networks

Selecting the appropriate polymer structure for use as both a solid electrolyte and catholyte is essential for enhancing the electrochemical performance of all-solid-state lithium metal batteries. In this study, we are pioneering the customization of solid electrolyte and catholyte synthesis based on novel polyrotaxane (PRX)-containing polymer networks by altering the length of the polyether crosslinkers to tune the properties to meet specific needs of different components. On one hand, the modified PRX polymer networks based on the shorter crosslinker show good mechanical strength, high ionic conductivity (7.25 × 10−4 S cm−1) and high lithium ions transference number (0.54) at 60 °C, allowing their use as solid polymer electrolyte (SPE) self-supporting membranes. On the other hand, all-solid-state lithium-ion batteries with this SPE demonstrate a much higher initial capacity (above 160 mAh/g using LiFePO4 as active material at the cathode and lithium metal as anode), and better cycling performance when paired with longer cross-linked PRX as catholytes than the other non-customized combinations all solid lithium-ion batteries. Moreover, the cycling performance of the full cell can be further improved by incorporating different lithium salts in the electrolyte (LiTFSI) and cathode (LiClO4). This work highlights that the customized design of solid electrolytes and catholytes based on polymer networks is an efficient strategy to obtain high-performance all-solid-state lithium metal batteries.

Ion-Selective Transport Promotion Enabled by Angstrom-Scale Nanochannels in Dendrimer-Assembled Polyamide Nanofilm for Efficient Electrodialysis.

The ion permeability and selectivity of membranes are crucial in nanofluidic behavior, impacting industries ranging from traditional to advanced manufacturing. Herein, we demonstrate the engineering of ion-conductive membranes featuring angstrom-scale ion-transport channels by introducing ionic polyamidoamine (PAMAM) dendrimers for ion separation. The exterior quaternary ammonium-rich structure contributes to significant electrostatic charge exclusion due to enhanced local charge density; the interior protoplasmic channels of PAMAM dendrimer are assembled to provide additional degrees of free volume. This facilitates the monovalent ion transfer while maintaining continuity and efficient ion screening. The dendrimer-assembled hybrid membrane achieves high monovalent ion permeance of 2.81 mol m-2 h-1 (K+), reaching excellent mono/multivalent selectivity up to 20.1 (K+/Mg2+) and surpassing the permselectivities of state-of-the-art membranes. Both experimental results and simulating calculations suggest that the impressive ion selectivity arises from the significant disparity in transport energy barrier between mono/multivalent ions, induced by the "exterior-interior" synergistic effects of bifunctional membrane channels.

Graphene oxide nanosheets reinforced quaternized poly(2,6-dimethyl-1,4-phenylene oxide) composite membranes with enhanced hydroxide ions conduction at subzero temperature

The realization of high hydroxide ion conductivity on the premise of enough alkaline stability is basic of the practical application of anion exchange membranes (AEMs). In this research, we propose a facile way to enhance the hydroxide ion conductivity at subzero temperature through constructing multilayered microstructures of AEMs. Graphene oxide (GO) nanosheets and 3,6-diazaspiro[5.5]undecane bromide (DSUBr) are alternately deposited on the surface of a quaternized poly(2,6-dimethyl-1,4-phenylene oxide) (QPPO) membrane with the layer by layer self-assembly process. Multilayered and compact microstructures are retained even if the prepared QPPO/(GO/DSUOH)5 membranes are immersed in 2 M KOH solution for 300 h. The hydroxide ions conduction resistance is reduced, deriving from the well-ordered dispersion of components. For example, the QPPO/2-(GO/DSUOH)5 membrane exhibits the hydroxide ion conductivities of 0.922 mS/cm at −25 °C and 58.5 mS/cm at 80 °C. Furthermore, the prepared AEMs possess the enhanced hydroxide ion conductivity owing to the fine dimension and component stabilities. After the ten-cycle hydroxide ion conductivity stability test, the retention rates of hydroxide ion conductivity are 99.4 % at −25 °C and 105 % at 30 °C. Additionally, the residual hydroxide ion conductivity reaches 61.6 mS/cm at 80 °C in 2 M KOH solution for 624 h. A single fuel cell equipped with the QPPO/2-(GO/DSUOH)5 membrane exhibits the maximum power densities of 80.8 mW/cm2 at 30 °C and 351.6 mW/cm2 at 60 °C.

Tuning the microstructure of biomass-derived hard carbons by controlling the impurity removal process for enhanced Na ion storage performance

Biomass-derived hard carbons are promising anode materials of sodium-ion batteries (SIBs) due to their low cost, renewability and high specific capacity. However, there are inevitably some impurities in biomasses that may not only affect the purity, but microstructure and electrochemical performance of hard carbons. Although the impurities can be removed by appropriate treatments after carbonization, the microstructure of hard carbons can hardly be changed. In this work, taking ficus macrophylla leaves (FMLs) as the model biomass, the effects of impurities and their removing process on the microstructure and Na ion storage performance of hard carbons are investigated. It is found that the presence of Ca and Si-bearing impurities in FMLs results in more graphite-like structure in hard carbons because of their catalytic graphitization effect. The acid and base washing processes after carbonization can mostly get rid of the inorganic impurities is unable to increase the plateau region capacities associating to Na ion insertion in the interlayer of graphitic microcrystals and Na metal filling in micropores. By contrast, by stepwisely removing the Ca and Si-bearing impurities from raw materials before carbonization, hard carbons with high purity, larger interlayer space and more micropores are produced, which exhibit a high reversible specific capacity of 336 mAh g−1 at 20 mA g−1, a high initial Coulombic efficiency of 93 %, excellent rate capability (245 mAh g−1 at 2 A g−1) and robust cycle stability. This study implies that controlling the impurity removal process can simultaneously tune the microstructure of hard carbon anodes derived from biomasses towards high performance Na ion storage.

Arc-enhanced glow discharge ion etching of WC-Co cemented carbide for improved PVD thin film adhesion and asymmetric cutting edge preparation of micro milling tools

Wear-resistant thin films on cutting tools require effective ion etching to enhance adhesion and thus extended tool service life. Arc enhanced glow discharge (AEGD) ion etching, characterized by high ionization degrees and high etch rates, was applied to ultrafine-grained WC-Co cemented carbide, commonly used for micromilling cutters. The effect of AEGD ion etching on the surface integrity of WC-Co and the resulting adhesion behavior of a TiAlSiN thin film was investigated by varying the etching time in comparison with conventional glow discharge (GD) ion etching. In addition, the impact of intensive etching on the cutting edge geometry of micro end cutters and, in turn, on the cutting performance in micromilling of hardened and annealed high-speed steel was evaluated.AEGD achieves remarkable etch rates of 12 nm/min at extended etching times, which are 100 times greater than conventional glow discharge (GD) ion etching. Prolonged AEGD ion etching for ≥30 min removes entire near-surface WC grains and exposes carbides beneath, resulting in increased surface roughness. After the etching process, polished WC-Co substrates exhibit a slight reduction in residual compressive stresses, which steadily decrease with increasing AEGD ion etching time. Furthermore, a TiAlSiN thin film demonstrates high adhesion on AEGD-etched surfaces compared to GD ion etching. Even a brief 5 min AEGD ion etching ensures the highest adhesion class according to the Rockwell C indentation test. Moreover, the intensive material removal results in significant changes in cutting edge geometry of micro end cutters, yielding substantial cutting edge rounding and an asymmetrical shape with form-factors Κ ≥ 2. In cutting tests, the resulting cutting edge geometries effectively reduce the wear formation and the associated wear-related increase in process forces during micromilling hardened and tempered powder metallurgical high-speed steel. In summary, AEGD ion etching emerges as a highly effective method for both enhancing thin film adhesion and preparing adapted asymmetrical cutting edge geometries for micromilling tools.

Voltammetry of the ferric/ferrous redox couple at platinum microelectrodes in aqueous hydrochloric acid

In this paper, the Fe3+/Fe2+ redox system was investigated in 0.5 M HCl solutions, using steady-state voltammetry at a Pt microelectrode. Measurements were performed in solutions containing each ion alone or in mixtures containing both ions. The reduction of Fe3+ to Fe2+ provided a single sigmoidal wave, regardless of the ion concentration. For the oxidation process of Fe2+ to Fe3+, a wave split was observed at relatively high ion concentrations (i.e., ≥ about 10 mM). This feature, not observed or not considered in previous studies, was rationalized by considering that the Fe2+ oxidation process occurs over the potential region where passivating Pt oxides form on the electrode surface. Standard rate constant (k0′), and transfer coefficient (α) of the electrode process were evaluated using the method based on the quartile potentials.ΔE1/4=E1/4-E1/2 and ΔE3/4=E1/2-E3/4, which can be obtained from the experimental steady-state voltammograms. k0′ and α values varied in the range 1.4 x10-3 cm s−1 to 3.1 x 10-2 cm s−1, and 0.44 – 0.64, respectively, depending on the specific status of the electrode surface, in turn depending on the care adopted in cleaning the electrode surface from the Pt oxides. From the quartile potentials approach, the formal potential of the redox system, equal to 0.495 (±0.005) V, vs. Ag/AgCl (KCl saturated) could also be evaluated. This value resulted in good agreement with 0.494 (±0.002) V, formal potential obtained from the cathodic-anodic voltammograms recorded in the mixtures of the two ions at equal concentration. Chronoamperometry was employed to determine the diffusion coefficients on the two ions, by fitting the experimental current against time profiles and the theoretical equation that holds for microdisk electrodes. The values found where 4.67 x 10-6 cm2 s−1 and 5.61 x 10-6 cm2 s−1 for Fe3+ and Fe2+ ions, respectively.

A soluble highly-sulfonated polybenzimidazole with high molecular weight as membrane for vanadium flow battery with enhanced performance and long-term stability

A series of novel sulfonated polybenzimidazole (SPBI) membranes containing flexible double ether segments, having high ion exchange capacity (IEC), good solubility as well as high molecular weight, are designed for vanadium flow batteries (VFBs). The bis-ether structure of self-synthesized sulfonic acid monomer, 4,4'-((2-sulfo-1,4-phenylene)bis(oxy))dibenzoic acid, improves the solubility of produced SPBI and the microphase separation structure of prepared membrane by disrupting the regularity of the backbone through a non-planar structure and attenuating the interchain stacking effect of the polymer backbone. Such a highly reactive bis-ether monomer also leads to high molecular weights (2.37−2.82 dL g−1). The copolymerization using another sulfonic acid monomer, Monosodium-5-Sulfoisophthalate monomer, leads to a high IEC of up to 2.08 mmol g−1. As a result, the SPBI membrane shows a low area resistance of 0.21 Ω cm2 and a low vanadium ion permeability of 3.36 × 10−9 cm2 s−1. The VFB cell employing SPBI membrane achieves a very high energy efficiency exceeding 82% at 200 mA cm−2. In addition, an ultra-long lifetime of over 3400 cycles is accomplished.

Characteristics of a hybrid radio frequency capacitively and inductively coupled plasma using hydrogen gas

A hybrid combination of a radio frequency (RF) capacitively coupled plasma (CCP) equipped with a ring-shaped hollow powered electrode and an inductively coupled plasma (ICP) with a helical antenna is investigated in hydrogen gas. Characteristics of the RF hybrid plasma are measured by a Langmuir probe at a fixed position in the center between the RF powered and grounded electrode for various CCP powers of 50–150 W. The voltage drop across the CCP is found to be almost independent of the ICP power. The RF hybrid plasma attains a high ion density of the order of 1010 cm−3 between the electrodes even at a low CCP input power of 50 W. The plasma density is strongly affected by the CCP generator power, while the floating potential is controlled by the ICP power, whereas the electron temperature is independent of the ICP power for various CCP powers. The negative ion production is enhanced by increasing the ICP power, resulting in a decrease in the ratio of the negative to the positive charge saturation current detected by the Langmuir probe. The maximum ratio of the negative ion density to the electron density is approximately 8 at a CCP power of 50 W and an ICP power of 250 W.

Selectivity filter mutations shift ion permeation mechanism in potassium channels.

Potassium (K+) channels combine high conductance with high ion selectivity. To explain this efficiency, two molecular mechanisms have been proposed. The "direct knock-on" mechanism is defined by water-free K+ permeation and formation of direct ion-ion contacts in the highly conserved selectivity filter (SF). The "soft knock-on" mechanism involves co-permeation of water and separation of K+ by water molecules. With the aim to distinguish between these mechanisms, crystal structures of the KcsA channel with mutations in two SF residues-G77 and T75-were published, where the arrangements of K+ ions and water display canonical soft knock-on configurations. These data were interpreted as evidence of the soft knock-on mechanism in wild-type channels. Here, we test this interpretation using molecular dynamics simulations of KcsA and its mutants. We show that while a strictly water-free direct knock-on permeation is observed in the wild type, conformational changes induced by these mutations lead to distinct ion permeation mechanisms, characterized by co-permeation of K+ and water. These mechanisms are characterized by reduced conductance and impaired potassium selectivity, supporting the importance of full dehydration of potassium ions for the hallmark high conductance and selectivity of K+ channels. In general, we present a case where mutations introduced at the critical points of the permeation pathway in an ion channel drastically change its permeation mechanism in a nonintuitive manner.

Synthesis of Low-Silicon X-Type Zeolite from Lithium Slag and Its Fast Exchange Performance of Calcium and Magnesium Ions.

Without the addition of silicon and aluminum sources, a pure-phase KNaLSX zeolite was successfully synthesized from the residue (lithium slag), which was produced from spodumene in the production process of lithium carbonate. The KNaLSX samples were characterized by an X-ray Diffractometer (XRD), Scanning Electron Microscope (SEM), X-ray Fluorescence Spectrometer (XRF), Thermogravimetric Differential Thermal Analysis (TG-DTA), Fourier Transform Infrared Spectrometer (FT-IR), and N2 adsorption measurement. The ion exchange capacity and the ion exchange rate of calcium and magnesium ions were measured as used for a detergent builder, and the results were compared with the standard zeolites (KNaLSX and 4A). The experimental results show that the pure-phase KNaLSX synthSynthesis and characterization of co-crystalline zeolite composite of LSX/esized from lithium slag has a SiO2/Al2O3 ratio of 2.01 with a grain size of 3~4 μm, which is close to the commercial KNaLSX sample of a SiO2/Al2O3 ratio of 2.0. The BET-specific surface area of KNaLSX is 715 m2/g, which is larger than the low-silicon X-type zeolite (LSX) synthesized from waste residue reported in the literature. The ion exchange rate constant of calcium and magnesium ions in KNaLSX is 5 times and 3 times that of 4A zeolite, respectively. KNaLSX also has a high ion exchange capacity for magnesium ion of 191 mgMgCO3/g, which is 2 times than that of 4A zeolite, and a high ion exchange capacity for calcium ion of 302 mgCaCO3/g, which meets the first-grade standard of zeolite for detergent builders in China. The work provides the basis for high-value resource utilization of lithium slag and the development of a detergent builder for rapid washing.

Single ion mobility monitoring (SIM2) stitching method for high-throughput and high ion mobility resolution chiral analysis

Chiral analysis is of high interest in many fields such as chemistry, pharmaceuticals and metabolomics. Mass spectrometry and ion mobility spectrometry are useful analytical tools, although they cannot be used as stand-alone methods. Here, we propose an efficient strategy for the enantiomer characterization of amino acids (AAs) using non-covalent copper complexes. A single ion mobility monitoring (SIM2) method was applied on a TIMS-ToF mass spectrometer to maximize the detection and mobility separation of isomers. Almost all of the 19 pairs of proteinogenic AA enantiomers could be separated with at least one combination with the chiral references L-Phe and L-Pro. Furthermore, we extended the targeted SIM2 method by stitching several mobility ranges, in order to be able to analyze complex mixtures in a single acquisition while maintaining high mobility resolution. Most of the enantiomeric pairs of AAs separated with the SIM2 method were also detected with this approach. The SIM2 stitching method thus opens the way to a more comprehensive chiral analysis with TIMS-ToF instruments.Graphical

Self‐Supporting Solid Electrolyte Based on Supramolecular Interaction for Stable Li Metal Batteries

AbstractLi metal batteries based on solid polymer electrolytes offer the benefits of high energy density and safety, as well as extended cycling life, making them an excellent candidate for the next‐generation battery system. However, current solid polymer electrolytes still suffer from low ion conductivity and Li+ transfer number, which seriously restricts its practical application. Herein, a self‐supporting composite solid polymer electrolyte was prepared, where phenolic resin rich in hydroxyl groups (BR) and polyethylene oxide (PEO) are mixed evenly and poured onto a cellulose membrane in one step. In such an electrolyte, PEO and BR combine to form intermolecular hydrogen bonds, lowering the crystallinity of PEO and increasing the Li+ transfer number. Lastly, the obtained solid electrolytes exhibited a high ion conductivity (1.1×10−4 S cm−1) and Li+ transfer number (0.53), as well as improved electrochemical window. Consequently, Li || Li symmetrical cells can run stably for more than 700 h at 0.1 mA cm−2/0.25 mAh cm−2. And full cells with LiFePO4 cathode can also demonstrate high discharge capacity of 152.12 mAh g−1 and rate performance. We believe that such a design based on supramolecular interaction offer a new avenue to advanced solid polymer electrolytes.

Optimizing Nanofluidic Energy Harvesting in Synthetic Clay-based Membranes by Annealing Treatment.

Nanofluidic energy harvesting from salinity gradients is studied in 2D nanomaterials-based membranes with promising performance as high ion selectivity and fast ion transport. In addition, moving forward to scalable, feasible systems requires environmentally friendly materials to make the application sustainable. Clay-based membranes are attractive for being environmentally friendly, non-hazardous, and easy to manipulate materials. However, achieving underwater stability for clay-based membranes remains challenging. In this work, the synthetic clay Laponite is used to prepare clay-based membranes with high stability and excellent performance for osmotic energy harvesting. The Laponite membranes (Lap-membranes) are stabilized by low-temperature annealing treatment to effectively reduce the interlayer space, achieving a continuous operation under salinity gradients. Furthermore, the Lap-membranes conserve integrity while soaking in water for more than one month. The output power density improves from ≈4.97W m-2 on the pristine membrane to ≈9.89W m-2 in the membrane treated 12 h at 300°C from a 30-fold concentration gradient. Especially, It is found that the presence of interlayer water to be favorable for ion transport. Different mechanisms are proposed in the Lap-membranes involved for efficient ion selectivity and the states found with varying annealing temperatures. This work demonstrates the potential application of Laponite based nanomaterials for nanofluidic energy harvesting.

Synthesis and electrochemical properties of activated lignite carbons-reduced graphene oxide nanocomposites symmetric supercapacitors

Ultra-fast chargeable or rechargeable symmetric carbon-based supercapacitors (SCSs) with high capacity, inexpensive, and non-flammability have attracted much attention for electronics and energy storage devices. However, improving both high redox reaction and ion transport/diffusion processes by enhancing high energy storage performance and rapid ion/electron transport SCSs electrode materials remains challenging. Herein, we presented a successful preparation of activated lignite carbons-reduced graphene oxide (ALC-rGO) nanocomposite (NCp) with the ALC:rGO ratio of 80:20 wt% by a one-pot hydrothermal for high electrochemical performance. Importantly, the matrix of ALC-rGO NCp was primary amorphous carbon with hexagonal graphitic layers and pore structures of plentiful micropores and mesopores. Remarkably, the ALC-rGO NCp electrode exhibited a maximum specific capacitance (Csc) of 152.12 F/g at 0.5 A/g. Interestingly, the SCSs-ACL-rGO device could illustrate a good performance at a potential voltage of 1.8 V with Csc of 50.90 F/g at 1 A/g and capacity retention of 96.0 % at 5 A/g after 2,000 cycles GCD test.

Stretchable interconnected modular electrochromic devices enabled by self-healing, self-adhesive, and ion-conducting polymer electrolyte

Here, we propose a versatile terpolymer electrolyte material, UPy-PEGMA-VBMI, comprised of three monomers: ureidopyrimidinone methacrylate (UPyMA), poly(ethylene glycol) methacrylate (PEGMA), and vinyl benzyl-methylimidazolium (VBMI). The UPy-PEGMA-VBMI, supported by a combination of soft ethylene glycol chains, an ion-conducting imidazole unit, and self-complementary quadruple hydrogen bonds of UPy, exhibits exceptional properties such as high stretchability, rapid self-repair, solution processability, self-adhesion, and ion conduction. The UPy-PEGMA-VBMI was then applied to make ion gel composite films, demonstrating a notable ionic conductivity of 3.84 × 10−3 S cm−1 while maintaining robust stretching and adhesive characteristics. The electrochromic devices (ECDs) fabricated by this ion gel demonstrate outstanding performance, with fast switching times, long-term kinetic stability, and extraordinarily high coloration efficiency of 443.83 cm2 C−1. The stretchable ECDs are fabricated by utilizing the stretchable nature of UPy-PEGMA-VBMI, exhibiting a transmittance contrast of 42.7 % at an extension of 53 % and operational stability during stretching cycles. Moreover, self-healing and self-adhesive features enable the fabrication of interconnected modular ECDs, implementing area-scalable devices. These modular ECDs, each powered independently, provide arbitrary positioning and shifting of individual device patches, overcoming the performance limitations of conventional large-area devices. The unprecedented material and resulting devices open new possibilities for electrochromic applications, particularly in stretchable ECDs, pattern-switching devices, and scalable flexible ECDs.

Three neo-Clerodane Diterpenoids from Tinospora cordifolia Stems and Their Arginase Inhibitory Activities.

Three neo-clerodane diterpenoids, including two new tinocordifoliols A (1) and B (2) and one known tinopanoid R (3), were isolated from the ethyl acetate-soluble fraction of the 70% ethanol extract of Tinospora cordifolia stems. The structures were elucidated by various spectroscopic methods, including one dimensional (1D) and 2D-NMR, high resolution-electrospray ionization (HR-ESI)-MS, and electronic circular dichroism (ECD) data. The T. cordifolia extract and all isolated compounds 1-3 possessed arginase I inhibitory activities. Among them, 3 exhibited moderate competitive inhibition of human arginase I (IC50 = 61.9 µM). Furthermore, docking studies revealed that the presence of a β-substituted furan in 3 may play a key role in the arginase I inhibitory activities.

Multiple-functional LiTi2(PO4)3 modification improving long-term performances of Li-rich Mn-based cathode material for advanced lithium-ion batteries

Li-rich layered oxides with high energy densities have become one kind of promising cathode for advanced lithium-ion batteries, however some issues are severely hindering their practical applications. To address these challenges, fast ion conductive LiTi2(PO4)3 (LTPO) is employed to modify the typical Li-rich cathode Li1·2Mn0·56Ni0·17Co0·07O2 (LMNCO) via a sol-gel process combined with a two-step annealing treatment in this work. Serving as a physical separator, LTPO coating effectively depresses the side reactions at cathode-electrolyte interface and the transition-metal dissolution from LMNCO active material under harsh electrochemical environment. Meanwhile, LTPO layer with high ion conductivity could facilitate the interfacial Li+ diffusion during charge/discharge process. In addition, partial Ti4+ ions doped into LMNCO effectively elevate the oxygen electronegativity and restrain the excessive oxidization of lattice oxygen, thus stabilizing the crystal structure and alleviating the stress-strain propagation upon cycling. Electrochemical characterization results demonstrate that the LTPO-modified LMNCO cathode exhibits a superior capacity retention of 86.5 % after 400 cycles at room temperature and that of 73.7 % even under an elevated temperature of 45 °C after 250 cycles under 1C. This study provides a facile strategy for the surface modification of Li-rich layered-structure oxides, which also sheds light in enhancing electrochemical performances for various cathode materials.