Tunneling Interpenetrative Lithium Ion Conduction Channels in Polymer-in-Ceramic Composite Solid Electrolytes.

Polymer-in-ceramic composite solid electrolytes (PIC-CSEs) provide important advantages over individual organic or inorganic solid electrolytes. In conventional PIC-CSEs, the ion conduction pathway is primarily confined to the ceramics, while the faster routes associated with the ceramic-polymer interface remain blocked. This challenge is associated with two key factors: (i) the difficulty in establishing extensive and uninterrupted ceramic-polymer interfaces due to ceramic aggregation; (ii) the ceramic-polymer interfaces are unresponsive to conducting ions because of their inherent incompatibility. Here, we propose a strategy by introducing polymer-compatible ionic liquids (PCILs) to mediate between ceramics and the polymer matrix. This mediation involves the polar groups of PCILs interacting with Li+ ions on the ceramic surfaces as well as the interactions between the polar components of PCILs and the polymer chains. This strategy addresses the ceramic aggregation issue, resulting in uniform PIC-CSEs. Simultaneously, it activates the ceramic-polymer interfaces by establishing interpenetrating channels that promote the efficient transport of Li+ ions across the ceramic phase, the ceramic-polymer interfaces, and the intervening pathways. Consequently, the obtained PIC-CSEs exhibit high ionic conductivity, exceptional flexibility, and robust mechanical strength. A PIC-CSE comprising poly(vinylidene fluoride) (PVDF) and 60 wt % PCIL-coated Li3Zr2Si2PO12 (LZSP) fillers showcasing an ionic conductivity of 0.83 mS cm-1, a superior Li+ ion transference number of 0.81, and an elongation of ∼300% at 25 °C could be produced on meter-scale. Its lithium metal pouch cells show high energy densities of 424.9 Wh kg-1 (excluding packing films) and puncture safety. This work paves the way for designing PIC-CSEs with commercial viability.

Characterization of a novel detergent-resistant type I pullulanase from Bacillus megaterium Y103 and its application in laundry detergent.

This study aims to find a moderate pullulanase for detergent industry. The pulY103B gene (2217 bp) from Bacillus megaterium Y103 was cloned and expressed in Escherichia coli. PulY103B contained four conserved regions of glycoside hydrolase family (GH) 13 and the typical sequence of type I pullulanase. The optimal reaction conditions of PulY103B were pH 6.5 and 40 °C. In addition, it remained stable below 40 °C and over 80% of activity was retained at pH ranging from 6.0 to 8.5. The best substrate for the enzyme was pullulan. Furthermore, it exhibited activity toward wheat starch (36.5%) and soluble starch (33.4%) but had no activity toward amylose and glycogen. Maltotriose and maltohexaose were major pullulan hydrolysis products. Soluble starch and amylopectin were mainly hydrolyzed into maltotetraose. These results indicated that PulY103B is a novel type I pullulanase with transglycosylation activity via formation of α-1,4-glucosidic linkages. Moreover, PulY103B was strongly stimulated by nonionic detergents [viz, Tween 20 (10%), Tween 80 (1%), Triton X-100 (20%)] and commercial liquid detergents (3.0 g/L). Wash performance tests demonstrated that the mixture of PulY103B and detergent removed starch-based stains better than using detergent alone (p < 0.05). Therefore, this pullulanase has big potential as a detergent additive.

Direct exfoliation of graphite to graphene by a facile chemical approach.

Facile exfoliation of graphite: High-quality graphene sheets are produced directly from graphite by a facile chemical approach. The new strategy for non-oxidized chemical exfoliation of graphite is based on a pre-intercalated process with oleum and a further strong reaction with sodium in the graphite layers under grinding conditions. This method is facile, low cost, and high throughput.

N-doped 3D carbon encapsulating nickel selenide nanoarchitecture with cation defect engineering: An ultrafast and long-life anode for sodium-ion batteries.

Transition metal chalcogenides (TMCs) hold great potential for sodium-ion batteries (SIBs) owing to their multielectron conversion reactions, yet face challenges of poor intrinsic conductivity, sluggish diffusion kinetics, severe phase transitions, and structural collapse during cycling. Herein, a self-templating strategy is proposed for the synthesis of a class of metal cobalt-doped NiSe nanoparticles confined within three-dimensional (3D) N-doped macroporous carbon matrix nanohybrids (Co-NiSe/NMC). The cation defect engineering within the developed Co-NiSe and 3D N-doped carbon plays a crucial role in enhancing intrinsic conductivity, reinforcing structural stability, and reducing the barrier to sodium ion diffusion, which are verified by a series of electrochemical kinetic analyses and density functional theory calculations. Significantly, such cation defect engineering not only reduces overpotential but also accelerates conversion reaction kinetics, ensuring both exceptional high-rate capability and extended durability. Consequently, the optimally engineered Co-NiSe/NMC demonstrates a remarkable rate performance, delivering 390 mAh g-1 at 10 A g-1. Moreover, it exhibits an unprecedented lifespan, maintaining a remarkable capacity of 403 mAh g-1 after 1400 cycles and 318 mAh g-1 after 4000 cycles, even at high rates of 1.0 and 2.0 A g-1, respectively. This work marks a substantial advancement in achieving both high performance and prolonged cycle life in sodium-ion batteries.

Controlled synthesis of highly crystalline MoS2 flakes by chemical vapor deposition.

The controlled synthesis of highly crystalline MoS2 atomic layers remains a challenge for the practical applications of this emerging material. Here, we developed an approach for synthesizing MoS2 flakes in rhomboid shape with controlled number of layers by the layer-by-layer sulfurization of MoO2 microcrystals. The obtained MoS2 flakes showed high crystallinity with crystal domain size of ~10 µm, significantly larger than the grain size of MoS2 grown by other methods. As a result of the high crystallinity, the performance of back-gated field effect transistors (FETs) made on these MoS2 flakes was comparable to that of FETs based on mechanically exfoliated flakes. This simple approach opens up a new avenue for controlled synthesis of MoS2 atomic layers and will make this highly crystalline material easily accessible for fundamental aspects and various applications.

Sucrose-assisted loading of LiFePO4 nanoparticles on graphene for high-performance lithium-ion battery cathodes.

A simple approach for loading LiFePO4 (LFP) nanoparticles on graphene (G) that could assemble amorphous LiFePO4 nanoparticles into a stable, crystalline, graphene-modified layered materials (G-S-LFP, S=sucrose) by using graphene as building block and sucrose as a linker has yet to be developed. On the basis of differential scanning calorimetric and transmission electron microscopy analysis of the samples from controlled experiment, a possible mechanism was proposed to explain the "linker" process of LFP and graphene with sucrose as the linker. The electrochemical properties of the samples as cathode material for lithium-ion batteries were studied by cyclic voltammogrametry and galvanostatic methods. Results showed that G-S-LFP displayed superior lithium-storage capability with current density changes randomly form 0.5 to 10 C. The significant improvement for rate and cycle performance could be attributed to the high conductivity of the graphene host, the high crystallinity, and the layered structure.

Decolorization and detoxification of a sulfonated triphenylmethane dye aniline blue by Shewanella oneidensis MR-1 under anaerobic conditions.

In this work, the extracellular decolorization of aniline blue, a sulfonated triphenylmethane dye, by Shewanella oneidensis MR-1 was confirmed. S. oneidensis MR-1 showed a high capacity for decolorizing aniline blue even at a concentration of up to 1,000 mg/l under anaerobic conditions. Maximum decolorization efficiency appeared at pH 7.0 and 30 °C. Lactate was a better candidate of electron donor for the decolorization of aniline blue. The addition of nitrate, hydrous ferric oxide, or trimethylamine N-oxide all could cause a significant decline of decolorization efficiency. The Mtr respiratory pathway was found to be involved into the decolorization of aniline blue by S. oneidensis MR-1. The toxicity evaluation through phytotoxicity and genotoxicity showed that S. oneidensis MR-1 could decrease the toxicity of aniline blue during the decolorization process. Thus, this work may facilitate a better understanding on the degradation mechanisms of the triphenylmethane dyes by Shewanella and is beneficial to their application in bioremediation.

Effects of Li+ conduction on the capacity utilization of cathodes in all-solid-state lithium batteries.

Li+ conduction in all-solid-state lithium batteries is limited compared with that in lithium-ion batteries based on liquid electrolytes because of the lack of an infiltrative network for Li+ transportation. Especially for the cathode, the practically available capacity is constrained due to the limited Li+ diffusivity. In this study, all-solid-state thin-film lithium batteries based on LiCoO2 thin films with varying thicknesses were fabricated and tested. To guide the cathode material development and cell design of all-solid-state lithium batteries, a one-dimensional model was utilized to explore the characteristic size for a cathode with varying Li+ diffusivity that would not constrain the available capacity. The results indicated that the available capacity of cathode materials was only 65.6% of the expected value when the area capacity was as high as 1.2 mAh/cm2. The uneven Li distribution in cathode thin films owing to the restricted Li+ diffusivity was revealed. The characteristic size for a cathode with varying Li+ diffusivity that would not constrain the available capacity was explored to guide the cathode material development and cell design of all-solid-state lithium batteries.

Confined WS2 Nanosheets Tubular Nanohybrid as High-Kinetic and Durable Anode for Sodium-Based Dual Ion Batteries.

Sodium based dual-ion battery (SDIB) has been regarded as one of the promising batteries technologies thanks to its high working voltage and natural abundance of sodium source, its practical application yet faces critical issues of low capacity and sluggish kinetics of intercalation-type graphite anode. Here, a tubular nanohybrid composed of building blocks of carbon-film wrapped WS2 nanosheets on carbon nanotube (WS2 /C@CNTs) was reported. The expanded (002) interlayer and dual-carbon confined structure endowed WS2 nanosheets with fast charge transportation and excellent structural stability, and thus WS2 /C@CNTs showed highly attractive electrochemical properties for Na+ storage with high reversible capacity, fast kinetic, and robust durability. The full sodium-based dual ion batteries by coupling WS2 /C@CNTs anode with graphite cathode full cell presented a high reversible capacity (210 mAh g-1 at 0.1 A g-1 ), and excellent rate performance with a high capacity of 137 mAh g-1 at 5.0 A g-1 .

Polyhedral AgBr microcrystals with an increased percentage of exposed {111} facets as a highly efficient visible-light photocatalyst.

Synthesis of inorganic single crystals with exposed high-reactivity facets is a desirable target in the catalytic chemistry field. Polyhedral AgBr microcrystals with an increased percentage of exposed high-reactivity {111} facets have been successfully prepared for the first time, and the photocatalytic performance of these microcrystals when used as an AgBr/Ag plasmonic photocatalyst was investigated. The results indicate that the as-prepared sample has high photocatalytic activity and, under the same measurement conditions, the photodegradation rate of methyl orange dye over these microcrystals is at least four times faster than with other shapes of AgBr/Ag microstructure, as well as 20 times faster than with the highly efficient Ag(3)PO(4) photocatalyst. DFT calculations suggest that the AgBr (111) surface is mainly composed of unsaturated Ag atoms and has a relatively high surface energy, both of which are favorable for enhancing the photocatalytic activity of the AgBr/Ag polyhedron photocatalyst. This work not only provides a highly efficient plasmonic photocatalyst of polyhedral AgBr/Ag microcrystals with an increased percentage of exposed high-reactivity AgBr {111} facets, but also demonstrates that the shape and crystalline quality of the exposed facets have an important influence on the photocatalytic activities.

A modified technique for culturing primary fetal rat cortical neurons.

The study explored a modified primary culture system for fetal rat cortical neurons. Day E18 embryos from pregnant Sprague Dawley rats were microdissected under a stereoscope. To minimize enzymatic damage to the cultured neurons, we applied a sequential digestion protocol using papain and Dnase I. The resulting sifted cell suspension was seeded at a density of 50,000 cells per cm(2) onto 0.1 mg/mL L-PLL-covered vessels. After a four-hour incubation in high-glucose Dulbecco's Modified Eagle's Medium (HG-DMEM) to allow the neurons to adhere, the media was changed to neurobasal medium that was refreshed by changing half of the volume after three days followed by a complete medium change every week. The cells displayed progressively robust neurite extension, and nonneuronal-like cells could barely be detected by five days in vitro (DIV); cell growth was still substantial at 14 DIV. Neurons were identified by ß-tubulin III immunofluorescence, and neuronal purity within the cultures was assessed at over 95% by both flow cytometry and by dark-field counting of ß-tubulin III-positive cells. These results suggest that the protocol was successful and that the high purity of neurons in this system could be used as the basis for generating various cell models of neurological disease.

Effect of alginate coatings incorporated with chitinase from 'Baozhu' pear on the preservation of cherry tomato during refrigerated storage.

The effects of edible coatings based on sodium alginate with 'Baozhu' pear chitinase on the quality of cherry tomatoes during refrigerated storage were evaluated. Cherry tomatoes inoculated with Fusarium oxysporum were coated and stored up to 21 days. All coatings with the chitinase significantly reduced F. oxysporum proliferation on cherry tomatoes during storage and extended the shelf life of cherry tomatoes effectively (p < .05). Results showed that alginate coatings with the chitinase could prevent weight loss, maintain firmness, and slow down the changes of titratable acidity and vitamin C (p < .05) in a dose-dependent manner. However, no significant differences were observed between T3 (1% alginate/0.15% 'Baozhu' pear chitinase/1% glycerin) and T4 (1% sodium alginate/0.3% 'Baozhu' pear chitinase/1% glycerin) (p > .05). Overall, alginate coating with 0.15% 'Baozhu' pear chitinase could be a promising method to maintain the quality of cherry tomatoes.

Enhancing ionic conductivity in solid electrolyte by relocating diffusion ions to under-coordination sites.

Solid electrolytes are highly important materials for improving safety, energy density, and reversibility of electrochemical energy storage batteries. However, it is a challenge to modulate the coordination structure of conducting ions, which limits the improvement of ionic conductivity and hampers further development of practical solid electrolytes. Here, we present a skeleton-retained cationic exchange approach to produce a high-performance solid electrolyte of Li3Zr2Si2PO12 stemming from the NASICON-type superionic conductor of Na3Zr2Si2PO12. The introduced lithium ions stabilized in under-coordination structures are facilitated to pass through relatively large conduction bottlenecks inherited from the Na3Zr2Si2PO12 precursor. The synthesized Li3Zr2Si2PO12 achieves a low activation energy of 0.21 eV and a high ionic conductivity of 3.59 mS cm-1 at room temperature. Li3Zr2Si2PO12 not only inherits the satisfactory air survivability from Na3Zr2Si2PO12 but also exhibits excellent cyclic stability and rate capability when applied to solid-state batteries. The present study opens an innovative avenue to regulate cationic occupancy and make new materials.

TiO2 Nanofiber-Modified Lithium Metal Composite Anode for Solid-State Lithium Batteries.

Solid-state lithium metal batteries (SSLMBs), using lithium metal as the anode and garnet-structured Li6.5La3Zr1.5Ta0.5O12 (LLZTO) as the electrolyte, are attractive and promising due to their high energy density and safety. However, the interface contact between the lithium metal and LLZTO is a major obstacle to the performance of SSLMBs. Here, we successfully improve the interface wettability by introducing one-dimensional (1D) TiO2 nanofibers into the lithium metal to obtain a Li-lithiated TiO2 composite anode (Li-TiO2). When 10 wt % TiO2 nanofibers are added, the formed composite anode offers a seamless interface contact with LLZTO and enables an interfacial resistance of 27 Ω cm2, which is much smaller than 374 Ω cm2 of pristine lithium metal. Due to the enhanced interface wettability, the symmetric Li-TiO2|LLZTO|Li-TiO2 cell upgrades the critical current density to 2.2 mA cm-2 and endures stable cycling over 550 h. Furthermore, by coupling the Li-TiO2 composite anode with the LiFePO4 cathode, the full cell shows stable cycling performance. This work proves the role of TiO2 nanofibers in enhancing the interface contact between the garnet electrolyte and the lithium metal anode and improving the performance of SSLMBs and provides an effective approach with 1D additives for solving the interface issues.

Li/Garnet Interface Optimization: An Overview.

Solid-state lithium batteries can improve the safety and energy density of the present liquid-electrolyte-based lithium-ion batteries. To achieve this goal, both solid electrolyte and lithium anode technology are the keys. Lithium garnet is a promising electrolyte to enable the next generation solid-state lithium batteries due to its high ionic conductivity, good chemical, and electrochemical stability, and easiness to scale up. It is relatively stable against Li metal but the poor contact area and the presence of resistive impurity or decomposition layers at the interface interfere with fast charge transfer, thereby, spiking the interfacial resistance, overpotential, local current density, and the propensity for dendrite growth. In this Review, we first summarize the recent understanding of the interfacial problems at the Li/garnet interface from both computational and experimental viewpoints while seizing the opportunity to shed light on the chemical/electrochemical stability of garnet against Li metal anode. Also, we highlight various interface optimization strategies that have been demonstrated to be effective in improving the interface performance. We conclude this Review with a few suggestions as guides for future work.

Preparation of Nanocomposite Polymer Electrolyte via In Situ Synthesis of SiO2 Nanoparticles in PEO.

Composite polymer electrolytes provide an emerging solution for new battery development by replacing liquid electrolytes, which are commonly complexes of polyethylene oxide (PEO) with ceramic fillers. However, the agglomeration of fillers and weak interaction restrict their conductivities. By contrast with the prevailing methods of blending preformed ceramic fillers within the polymer matrix, here we proposed an in situ synthesis method of SiO2 nanoparticles in the PEO matrix. In this case, robust chemical interactions between SiO2 nanoparticles, lithium salt and PEO chains were induced by the in situ non-hydrolytic sol gel process. The in situ synthesized nanocomposite polymer electrolyte delivered an impressive ionic conductivity of ~1.1 × 10-4 S cm-1 at 30 °C, which is two orders of magnitude higher than that of the preformed synthesized composite polymer electrolyte. In addition, an extended electrochemical window of up to 5 V vs. Li/Li+ was achieved. The Li/nanocomposite polymer electrolyte/Li symmetric cell demonstrated a stable long-term cycling performance of over 700 h at 0.01-0.1 mA cm-2 without short circuiting. The all-solid-state battery consisting of the nanocomposite polymer electrolyte, Li metal and LiFePO4 provides a discharge capacity of 123.5 mAh g-1, a Coulombic efficiency above 99% and a good capacity retention of 70% after 100 cycles.

Dual Substitution and Spark Plasma Sintering to Improve Ionic Conductivity of Garnet Li7La3Zr2O12.

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 ≤ x ≤ 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 × 10-4 S cm-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 °C is 8.8 × 10-4 S cm-1, and that of Li6.6La3Zr1.6Ta0.4O12 sintered at 1050 °C is 1.18 × 10-3 S cm-1.

Highly Adhesive Li-BN Nanosheet Composite Anode with Excellent Interfacial Compatibility for Solid-State Li Metal Batteries.

Solid-state lithium metal batteries (SSLMBs) are promising energy storage devices by employing lithium metal anodes and solid-state electrolytes (SSEs) to offer high energy density and high safety. However, their efficiency is limited by Li metal/SSE interface barriers, including insufficient contact area and chemical/electrochemical incompatibility. Herein, a strategy to effectively improve the adhesiveness of Li metal to garnet-type SSE is proposed by adding only a few two-dimensional boron nitride nanosheets (BNNS) (5 wt %) into Li metal by triggering the transition from point contact to complete adhesion between Li metal and ceramic SSE. The interface between the Li-BNNS composite anode and the garnet exhibits a low interfacial resistance of 9 Ω cm2, which is significantly lower than that of bare Li/garnet interface (560 Ω cm2). Furthermore, the enhanced contact and the additional BNNS in the interface act synergistically to offer a high critical current density of 1.5 mA/cm2 and a stable electrochemical plating/striping over 380 h. Moreover, the full cell paired with the Li-BNNS composite anode and the LiFePO4 cathode shows stable cycling performance at room temperature. Our results introduce an appealing composite strategy with two-dimensional materials to overcome the interface challenges, which provide more opportunities for the development of SSLMBs.

Association of lower leukocyte count before thrombolysis with early neurological improvement in acute ischemic stroke patients.

Early neurological improvement (ENI) after thrombolysis in acute ischemic stroke is associated with a favorable long-term outcome. With the goal to evaluate ENI, we aimed to investigate whether ENI bears a relationship with routine blood tests before thrombolysis. A total of 240 patients with confirmed early ischemic stroke and intravenous recombinant tissue plasminogen activator (rtPA) treatment were enrolled from two teaching hospitals, between June 2010 and March 2016. The primary endpoint was ENI that was defined as a decrease of National Institutes of Health Stroke Scale (NIHSS) scores ≥4 points or complete recovery in 24 h after thrombolysis. Patients underwent NIHSS score evaluation and head CT scan before and after 24 h of IV rtPA treatment. Blood samples for routine blood tests were drawn at admission before IV rtPA administration. Multivariate regression analysis was used to explore the relationship between test results and ENI. Of the results of routine blood tests, leukocyte count before thrombolysis was found to associated independently with ENI (adjusted odds ratio[adjOR] = 0.894, P = 0.025, 95% CI = 0.810-0.986). Onset-to-treatment time (OTT; adjOR = 0.993, P = 0.003, 95% CI = 0.988-0.997) and negative CT sign (adjOR = 3.975, P < 0.001, 95% CI = 1.916-8.246) both were associated with ENI. The change of NIHSS score after 24 h of thrombolysis correlated with the leukocyte and neutrophil count, and neutrophil-to-lymphocyte ratio. A model that combined leukocyte count, positive CT sign, and OTT was generated to predict non-ENI (AUC = 0.717). Therefore, we determined that the leukocyte count was independently associated with ENI. Predicting non-ENI aid in selecting patients for mechanical thrombectomy after thrombolysis.