21 research outputs found

    Nanoporous ceramic-poly(ethylene oxide) composite electrolyte for sodium metal battery.

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    The exploration of solid polymer electrolytes with both superior ionic conductivity and high mechanical stability for sodium-metal batteries still remains dramatical challenges. Herein, we report a composite electrolyte fabricated by sandwiching nanoporous ceramic with a poly(ethylene oxide) (PEO) base polymer electrolyte. This laminated configuration yields superior ionic conductivity of 1.6x 10ˉ⁴ S cmˉ¹ at room temperature, stable Na plating and stripping, as well as wide potential stability window of 4.2 V vs Na/Na+

    Interfacial engineering for high‐performance garnet‐based solid‐state lithium batteries

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    Abstract Solid‐state batteries represent the future of energy storage technology, offering improved safety and energy density. Garnet‐type Li7La3Zr2O12 (LLZO) solid‐state electrolytes‐based solid‐state lithium batteries (SSLBs) stand out for their appealing material properties and chemical stability. Yet, their successful deployment depends on conquering interfacial challenges. This review article primarily focuses on the advancement of interfacial engineering for LLZO‐based SSLBs. We commence with a concise introduction to solid‐state electrolytes and a discussion of the challenges tied to interfacial properties in LLZO‐based SSLBs. We deeply explore the correlations between structure and properties and the design principles vital for achieving an ideal electrode/electrolyte interface. Subsequently, we delve into the latest advancements and strategies dedicated to overcoming these challenges, with designated sections on cathode and anode interface design. In the end, we share our insights into the advancements and opportunities for interface design in realizing the full potential of LLZO‐based SSLBs, ultimately contributing to the development of safe and high‐performance energy storage solutions

    Anchoring Nanostructured Manganese Fluoride on Few-Layer Graphene Nanosheets as Anode for Enhanced Lithium Storage

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    Manganese fluoride (MnF<sub>2</sub>)/few-layer graphene nanosheets (GNS) composites are successfully prepared via a facile solvothermal method. It is found that in situ formed tetragonal MnF<sub>2</sub> submicron crystals (50–200 nm) with good crystallinity anchoring homogeneously onto conducting GNS, allows the electrically insulating MnF<sub>2</sub> particles to be wired up to the current collector with enhanced electron transport pathway. The MnF<sub>2</sub>/GNS composites act as anode in LIBs and display prominently improved electrochemical performance in comparison to that of pure MnF<sub>2</sub>, on account of the close interactions between the underlying graphene nanosheets and MnF<sub>2</sub> particles grown atop. Distinctly enhanced capacity as high as 489 mAh g<sup>–1</sup> after 100 cycles can be obtained at 600 mA g<sup>–1</sup>, while the self-activation process can be greatly accelerated at 6000 mA g<sup>–1</sup> with a maximum specific capacity of 530 mAh g<sup>–1</sup>. With long cycling stability for 4000 cycles at 6000 mA g<sup>–1</sup>, the MnF<sub>2</sub>/GNS composite can be deemed as an attractive candidate anode for high-capacity, long cycle life, and environmentally friendly LIBs

    Dual Substitution and Spark Plasma Sintering to Improve Ionic Conductivity of Garnet Li<sub>7</sub>La<sub>3</sub>Zr<sub>2</sub>O<sub>12</sub>

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    Garnet Li7La3Zr2O12 is one of the most promising solid electrolytes used for solid-state lithium batteries. However, low ionic conductivity impedes its application. Herein, we report Ta-doping garnets with compositions of Li7-xLa3Zr2-xTaxO12 (0.1 &#8804; x &#8804; 0.75) obtained by solid-state reaction and free sintering, which was facilitated by graphene oxide (GO). Furthermore, to optimize Li6.6La3Zr1.6Ta0.4O12, Mg2+ was select as a second dopant. The dual substitution of Ta5+ for Zr4+ and Mg2+ for Li+ with a composition of Li6.5Mg0.05La3Zr1.6Ta0.4O12 showed an enhanced total ionic conductivity of 6.1 &#215; 10&#8722;4 S cm&#8722;1 at room temperature. Additionally, spark plasma sintering (SPS) was applied to further densify the garnets and enhance their ionic conductivities. Both SPS specimens present higher conductivities than those produced by the conventional free sintering. At room temperature, the highest ionic conductivity of Li6.5Mg0.05La3Zr1.6Ta0.4O12 sintered at 1000 &#176;C is 8.8 &#215; 10&#8722;4 S cm&#8722;1, and that of Li6.6La3Zr1.6Ta0.4O12 sintered at 1050 &#176;C is 1.18 &#215; 10&#8722;3 S cm&#8722;1

    The effect of telerehabilitation on balance in stroke patients: is it more effective than the traditional rehabilitation model? A meta-analysis of randomized controlled trials published during the COVID-19 pandemic

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    ObjectiveTelerehabilitation and telemedicine have gradually gained popularity. In 2019, the outbreak of COVID-19 started in Wuhan and then spread across the world. To date, most countries have opted to coexist with the virus. However, patients, especially those who have suffered a stroke, should take measures to avoid being infected with any disease as much as possible since any infectious disease can lead to adverse events for them. Telerehabilitation can be beneficial to stroke patients as they are less likely to be infected by the virus. In recent years, several studies on telerehabilitation have been conducted globally. This meta-analysis aimed to investigate the effects of telerehabilitation on the balance ability of stroke patients, compare the efficacy of conventional rehabilitation with telerehabilitation, explore the characteristics of telerehabilitation and conventional rehabilitation, and provide recommendations for rehabilitation programs in the context of the global pandemic.MethodsWe searched Pubmed, Embase, the Web of Science, and The Cochrane Library databases from 1 January 2020 to 31 December 2022 for randomized controlled trials published in English that evaluated the improvement of balance function in stroke patients after telerehabilitation and compared the differences between telerehabilitation (TR) and conventional rehabilitation (CR). The random-effects model was utilized to calculate mean differences (MDs) with 95% confidence intervals (CIs) to estimate intervention effects. Statistical heterogeneity was assessed according to the I2 values. The risk of bias was measured using the Cochrane risk-of-bias assessment tool.ResultsWe included nine studies in the system evaluation, all of which were included in the pooled analysis. All outcomes in the experimental and control groups improved over time. The comparison between groups concluded that people who received the telerehabilitation intervention had a significant improvement in the Berg Balance Scale (MD = 2.80; 95% CI 0.61, 4.98, P &lt; 0.05, I2 = 51.90%) and the Fugl-Meyer Assessment (MD = 8.12; 95% CI 6.35, 9.88, P &lt; 0.05, I2 = 0) compared to controls. The Timed Up and Go test (MD = −4.59; 95% CI −5.93, –.25, P &lt; 0.05, I2 = 0) and Tinetti Performance-Oriented Mobility Assessment—Balance (MD = 2.50; 95% CI 0.39, 4.61, P &lt; 0.05) scored better in the control group than in the experimental group. There were no significant differences in other outcomes between the two groups.ConclusionStudies on changes in medical conditions during the COVID-19 pandemic also demonstrated that, for stroke patients, telerehabilitation achieves similar effects as the conventional rehabilitation model and can act as a continuation of the conventional rehabilitation model. Owing to the different equipment and intervention programs of telerehabilitation, its curative effect on the static balance and reactive balance of stroke patients may be different. Currently, telerehabilitation may be more conducive to the rehabilitation of patients' static balance abilities, while conventional rehabilitation is more effective for the rehabilitation of patients' reactive balance. Therefore, further studies are needed for investigating the difference in efficacy between varied devices and telerehabilitation programs. Further research is needed on static and reactive balance. In addition, such research should have a large body of literature and a large sample size to support more definitive findings based on the context of the COVID-19 pandemic.Systematic review registrationCRD42023389456

    Method Using Water-Based Solvent to Prepare Li<sub>7</sub>La<sub>3</sub>Zr<sub>2</sub>O<sub>12</sub> Solid Electrolytes

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    Li-garnet Li<sub>7</sub>La<sub>3</sub>Zr<sub>2</sub>O<sub>12</sub> (LLZO) is a promising candidate of solid electrolytes for high-safety solid-state Li<sup>+</sup> ion batteries. However, because of its high reactivity to water, the preparation of LLZO powders and ceramics is not easy for large-scale amounts. Herein, a method applying water-based solvent is proposed to demonstrate a possible solution. Ta-doped LLZO, that is, Li<sub>6.4</sub>La<sub>3</sub>Zr<sub>1.4</sub>Ta<sub>0.6</sub>O<sub>12</sub> (LLZTO), and its LLZTO/MgO composite ceramics are made by attrition milling, followed by a spray-drying process using water-based slurries. The impacts of parameters of the method on the structure and properties of green and sintered pellets are studied. A relative density of ∼95%, a Li-ion conductivity of ∼3.5 × 10<sup>–4</sup> S/cm, and uniform grain size LLZTO/MgO garnet composite ceramics are obtained with an attrition-milled LLZTO/MgO slurry that contains 40 wt % solids and 2 wt % polyvinyl alcohol binder. Li–sulfur batteries based on these ceramics are fabricated and work under 25 °C for 20 cycles with a Coulombic efficiency of 100%. This research demonstrates a promising mass production method for the preparation of Li-garnet ceramics

    Image1_Comparative and evolutionary analysis of RIP kinases in immune responses.TIF

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    The group of receptor-interacting protein (RIP) kinases has seven members (RIPK1–7), with one homologous kinase domain but distinct non-kinase regions. Although RIPK1–3 have emerged as key modulators of inflammation and cell death, few studies have connected RIPK4–7 to immune responses. The divergence in domain structures and paralogue information in the Ensembl database have raised question about the phylogeny of RIPK1–7. In this study, phylogenetic trees of RIPK1–7 and paralogues constructed using full-length amino acid sequences or Kinase domain demonstrate that RIPK6 and RIPK7 are distinct from RIPK1–5 and paralogues shown in the Ensembl database are inaccurate. Comparative and evolutionary analyses were subsequently performed to gain new clues about the potential functions of RIPK3–7. RIPK3 gene loss in birds and animals that undergo torpor, a common physiological phenomenon in cold environments, implies that RIPK3 may be involved in ischemia-reperfusion injury and/or high metabolic rate. The negligible expression of RIPK4 and RIPK5 in immune cells is likely responsible for the lack of studies on the direct role of these members in immunity; RIPK6 and RIPK7 are conserved among plants, invertebrates and vertebrates, and dominantly expressed in innate immune cells, indicating their roles in innate immunity. Overall, our results provide insights into the multifaceted and conserved biochemical functions of RIP kinases.</p

    Sulfonic Groups Originated Dual-Functional Interlayer for High Performance Lithium–Sulfur Battery

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    The lithium–sulfur battery is one of the most prospective chemistries in secondary energy storage field due to its high energy density and high theoretical capacity. However, the dissolution of polysulfides in liquid electrolytes causes the shuttle effect, and the rapid decay of lithium sulfur battery has greatly hindered its practical application. Herein, combination of sulfonated reduced graphene oxide (SRGO) interlayer on the separator is adopted to suppress the shuttle effect. We speculate that this SRGO layer plays two roles: physically blocking the migration of polysulfide as ion selective layer and anchoring lithium polysulfide by the electronegative sulfonic group. Lewis acid–base theory and density functional theory (DFT) calculations indicate that sulfonic groups have a strong tendency to interact with lithium ions in the lithium polysulfide. Hence, the synergic effect involved by the sulfonic group contributes to the enhancement of the battery performance. Furthermore, the uniformly distributed sulfonic groups working as active sites which could induce the uniform distribution of sulfur, alleviating the excessive growth of sulfur and enhancing the utilization of active sulfur. With this interlayer, the prototype battery exhibits a high reversible discharge capacity of more than 1300 mAh g<sup>–1</sup> and good capacity retention of 802 mAh g<sup>–1</sup> after 250 cycles at 0.5 C rate. After 60 cycles at different rates from 0.2 to 4 C, the cell with this functional separator still recovered a high specific capacity of 1100 mAh g<sup>–1</sup> at 0.2 C. The results demonstrate a promising interlayer design toward high performance lithium–sulfur battery with longer cycling life, high specific capacity, and rate capability

    Two-Dimensional Sulfonate-Functionalized Metal–Organic Framework Membranes for Efficient Lithium-Ion Sieving

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    Two-dimensional (2D) membranes have shown promising potential for ion-selective separation but often suffer from the trade-off between permeability and selectivity. Herein, we report an ultrathin 2D sulfonate-functionalized metal–organic framework (MOF) membrane for efficient lithium-ion sieving. The narrow pores with angstrom precision in the MOF assist hydrated ions to partially remove the hydration shell, according to different hydration energies. The abundant sulfonate groups in the MOF channels serve as hopping sites for fast lithium-ion transport, contributing to a high Li-ion permeability. Then, the difference in affinity of the Li+, Na+, K+, and Mg2+ ions to the terminal sulfonate groups further enhances the Li-ion selectivity. The reported ultrathin MOF membrane overcomes the trade-off between permeability and selectivity and opens up a new avenue for highly permselective membranes
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