The electrochemical oxygen evolution reaction (OER) is a key process in many renewable energy systems. The development of low‐cost, long‐lasting alternatives to precious‐metal catalysts, particularly ...functional electrocatalysts with high activity for OER processes, is crucial for reducing the operating expense and complexity of renewable energy generating systems. This work describes a concise method for generating marigold flower‐like metal–organic frameworks (MOFs) aided manganese vanadium oxide via a hydrothermal procedure for increased OER activity. As synthesized MOF MnV oxide has a higher surface area due to the 3D flower‐like structure, which is reinvented with enhanced electrocatalytic active sites. These distinctive structural features result in remarkable catalytic activity for MOF MnV oxide microflowers towards OER with a low overpotential of 310 mV at 50 mA cm−2 and a Tafel slope with only 51.4 mV dec−1 in alkaline conditions. This study provides a concise method for developing an optimized catalytic material with greater morphology and beneficial features for potential energy and environmental applications.
Marigold flower‐shaped metal–organic framework assisted manganese vanadium oxide was synthesized using a facile hydrothermal approach and employed as electrocatalysts for electrochemical water oxidation. The electrocatalytic activity and stability of MOF MnV oxide microflower toward O2 evolution processes are superior. Water electrolyzers based on MOF MnV oxide microflower catalyst are comparable to those based on commercial IrO2 catalysts.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Due to its outstanding safety and high energy density, all‐solid‐state lithium‐sulfur batteries (ASLSBs) are considered as a potential future energy storage technology. The electrochemical reaction ...pathway in ASLSBs with inorganic solid‐state electrolytes is different from Li‐S batteries with liquid electrolytes, but the mechanism remains unclear. By combining operando Raman spectroscopy and ex situ X‐ray absorption spectroscopy, we investigated the reaction mechanism of sulfur (S8) in ASLSBs. Our results revealed that no Li2S8, Li2S6, and Li2S4 were formed, yet Li2S2 was detected. Furthermore, first‐principles structural calculations were employed to disclose the formation energy of solid state Li2Sn (1≤n≤8), in which Li2S2 was a metastable phase, consistent with experimental observations. Meanwhile, partial S8 and Li2S2 remained at the full lithiation stage, suggesting incomplete reaction due to sluggish reaction kinetics in ASLSBs.
Utilizing operando Raman spectroscopy and ex situ synchrotron X‐ray absorption spectroscopy, the electrochemical reaction mechanisms of the sulfur cathode in all‐solid‐state batteries are revealed. The results demonstrated that no Li2S6 and Li2S4 is formed but Li2S2 is observed. Furthermore, first‐principles calculations disclose the formation energy of solid state Li2Sn (1≤n≤8), in which Li2S2 is a metastable phase.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
The practical application of lithium (Li) metal anode (LMA) is still hindered by non‐uniformity of solid electrolyte interphase (SEI), formation of “dead” Li, and continuous consumption of ...electrolyte although LMA has an ultrahigh theoretical specific capacity and a very low electrochemical redox potential. Herein, a facile protection strategy is reported for LMA using a double layer (DL) coating that consists of a polyethylene oxide (PEO)‐based bottom layer that is highly stable with LMA and promotes uniform ion flux, and a cross‐linked polymer‐based top layer that prevents solvation of PEO layer in electrolytes. Li deposited on DL‐coated Li (DL@Li) exhibits a smoother surface and much larger size than that deposited on bare Li. The LiF/Li2O enriched SEI layer generated by the salt decomposition on top of DL@Li further suppresses the side reactions between Li and electrolyte. Driven by the abovementioned advantageous features, the DL@Li||LiNi0.6Mn0.2Co0.2O2 cells demonstrate capacity retention of 92.4% after 220 cycles at a current density of 2.1 mA cm–2 (C/2 rate) and stability at a high charging current density of 6.9 mA cm–2 (1.5 C rate). These results indicate that the DL protection is promising to overcome the rate limitation of LMAs and high energy‐density Li metal batteries.
The double‐layer (DL) protection is designed by a polyethylene oxide (PEO)‐based bottom layer that promotes uniform ion flux and a cross‐linked polymer‐based top layer that suppresses the solvation of the PEO layer in electrolytes. The DL‐coated Li (DL@Li) allows the generation of LiF/Li2O enriched‐solid electrolyte interphase and the stable electrochemical performance of DL@Li||LiNi0.6Mn0.2Co0.2O2 cells at a high charge current density.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Using fast time‐resolved in situ X‐ray diffraction, charge‐rate dependent phase transition processes of layer structured cathode material LiNi1/3Mn1/3Co1/3O2 for lithium‐ion batteries are studied. ...During first charge, intermediate phases emerge at high rates of 10C, 30C, and 60C, but not at low rates of 0.1C and 1C. These intermediate phases can be continuously observed during relaxation after the charging current is switched off. After half‐way charging at high rate, sample studied by scanning transmission electron microscopy shows Li‐rich and Li‐poor phases' coexistence with tetrahedral occupation of Li in Li‐poor phase. The high rate induced overpotential is thought to be the driving force for the formation of this intermediate Li‐poor phase. The in situ quick X‐ray absorption results show that the oxidation of Ni accelerates with increasing charging rate and the Ni4+ state can be reached at the end of charge with 30C rate. These results give new insights in the understanding of the layered cathodes during high‐rate charging.
Intermediate phases are revealed in LiNi1/3Mn1/3Co1/3O2 (NMC) cathode during charge at 10C rate, and become more pronounced at 30C and 60C. Li tetrahedral site occupation becomes possible when high rates are applied. The charge compensation contribution by Ni ions is faster and more effective at higher C rate, suggesting the benefit of higher Ni content in NMC for rate capability.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Organic electrochemical transistors that employ polymeric mixed conductors as their active channels are one of the most prominent biosensor platforms because of their signal amplification capability, ...low fabrication cost, mechanical flexibility, and various properties tunable through molecular design. For application to biomedical devices, polymeric mixed conductors should fulfill several requirements, such as excellent conductivities of both holes/electrons and ions, long‐term operation stability, and decent biocompatibility. However, trade‐offs may exist, for instance, one between ionic conduction and overall device stability. In this report, the fundamental understanding of polymeric mixed conductors, the recent advance in enhancing their ionic and electrical conductivity, and their practical applications as biosensors based on organic electrochemical transistors are reviewed. Finally, key strategies are suggested for developing novel polymeric mixed conductors that may exceed the trade‐off between device performance and stability.
Organic electrochemical transistor (OECT)‐based biosensors are expected to have a broad impact on the future bioelectronics due to the biocompatibility and electronic/ionic mixed conducting characteristics of polymeric mixed conductors with ion permeability. This article reviews the recent advances made in polymeric mixed conductors and the structure–property relationship, and suggest the ideal structure and outlook for high‐performance, stable OECT‐based biomedical applications.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Isoflavones and their derivatives possess neuroprotective activities against neurological disorders. Recently, the active compound SPA1413 (dehydroequol) derived from S-equol, an isoflavone-derived ...metabolite produced by human intestinal bacteria, was identified as a potent anti-amyloidogenic and neuroinflammatory candidate against Alzheimer’s disease. However, its detailed modes of action, associated signaling pathways, and comparison with potential isoflavone derivatives have not yet been studied. Hence, the current study aimed to identify signaling pathways associated with SPA1413 using lipopolysaccharides (LPS)-stimulated BV2 cells as the experimental model via biological assays, Western blotting, and quantitative (q)RT-PCR. The results indicate that the SPA1413 anti-neuroinflammatory effect arises due to suppression of the nitric oxide (NO), interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), cyclooxygenase-2 (COX-2), inducible nitric oxide synthase (iNOS), and mitogen-activated protein kinase (MAPK) signaling networks, including those of p38 and c-Jun N-terminal kinase (JNK). Interestingly, SPA1413 inhibited IL-11 through the Janus kinase (JAK)/signal transducer and activator of transcription (STAT) signaling pathway. In addition, SPA1413 inhibited neuronal cell death by reducing LPS-activated microglia in neuronal N2a cells. Our findings suggest that SPA1413 may act as a strong anti-neuroinflammatory candidate by suppressing the MAPK and JAK/STAT signaling pathways.
Obesity is known to be associated with increased inflammation and dysregulated autophagy, both of which contribute to insulin resistance. Saikosaponin-A (SSA) has been reported to exhibit ...anti-inflammatory and lipid-lowering properties. In this research, we employed a combination of computational modeling and animal experiments to explore the effects of SSA. Male C57BL/6 mice were categorized into four groups: normal diet, high-fat diet (HFD), HFD + atorvastatin 10 mg/kg, and HFD + SSA 10 mg/kg. We conducted oral glucose and fat tolerance tests to assess metabolic parameters and histological changes. Furthermore, we evaluated the population of Kupffer cells (KCs) and examined gene expressions related to inflammation and autophagy. Computational analysis revealed that SSA displayed high binding affinity to tumor necrosis factor (TNF)-α, nuclear factor (NF)-κB, fibroblast growth factor 21 (FGF21), and autophagy-related 7 (ATG7). Animal study demonstrated that SSA administration improved fasting and postprandial glucose levels, homeostatic model assessment of insulin resistance (HOMA-IR) index, as well as triglyceride, free fatty acid, total cholesterol, low-density lipoprotein cholesterol (LDL-C)-cholesterol, and high-density lipoprotein cholesterol (HDL-C)-cholesterol levels in HFD-fed mice. Moreover, SSA significantly reduced liver weight and fat accumulation, while inhibiting the infiltration and M1 activation of KCs. At the mRNA level, SSA downregulated TNF-α and NF-κB expression, while upregulating FGF21 and ATG7 expression. In conclusion, our study suggests that SSA may serve as a therapeutic agent for addressing the metabolic complications associated with obesity. This potential therapeutic effect is attributed to the suppression of inflammatory cytokines and the upregulation of FGF21 and ATG7.
High rate capability and long cycle life are challenging goals for the development of room temperature sodium-ion batteries. Here we report a new single phase quaternary O3-type layer-structured ...transition metal oxide Na(NiCoFeTi)1/4O2 synthesized by a simple solid-state reaction as a new cathode material for sodium-ion batteries. It can deliver a reversible capacity of 90.6 mA h g-1 at a rate as high as 20C. At 5C, 75.0% of the initial specific capacity can be retained after 400 cycles with a capacity-decay rate of 0.07% per cycle, demonstrating a superior long-term cyclability at high current density. X-ray diffraction and absorption characterization revealed reversible phase transformations and electronic structural changes during the Na+ deintercalation/intercalation process. Ni, Co and Fe ions contribute to charge compensation during charge and discharge. Although Ti ions do not contribute to the charge transfer, they play a very important role in stabilizing the structure during charge and discharge by suppressing the Fe migration. In addition, Ti substitution can also smooth the charge-discharge plateaus effectively, which provides a potential advantage for the commercialization of this material for room temperature sodium-ion batteries.
Background The incidence of food allergies has increased dramatically during the last decade. Recently, probiotics have been studied for the prevention and treatment of allergic disease. Objective We ...examined whether Bifidobacterium longum KACC 91563 and Enterococcus faecalis KACC 91532 have the capacity to suppress food allergies. Methods B longum KACC 91563 and E faecalis KACC 91532 were administered to BALB/c wild-type mice, in which food allergy was induced by using ovalbumin and alum. Food allergy symptoms and various immune responses were assessed. Results B longum KACC 91563, but not E faecalis KACC 91532, alleviated food allergy symptoms. Extracellular vesicles of B longum KACC 91563 bound specifically to mast cells and induced apoptosis without affecting T-cell immune responses. Furthermore, injection of family 5 extracellular solute-binding protein, a main component of extracellular vesicles, into mice markedly reduced the occurrence of diarrhea in a mouse food allergy model. Conclusion B longum KACC 91563 induces apoptosis of mast cells specifically and alleviates food allergy symptoms. Accordingly, B longum KACC 91563 and family 5 extracellular solute-binding protein exhibit potential as therapeutic approaches for food allergies.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
In this work, we have developed a side by side nanofibers (SBS NFs) by a versatile electrospinning technique using a self-designed nozzle that allows the ejecting of the solution simultaneously in a ...side by side manner. The as-designed fiber was composed of Zinc oxide nanoparticles (ZnO NPs) on one side while silver nanoparticles (Ag NPs) on the other side, thereby forming a coupled fiber with a property of photo catalysis and antibacterial properties, respectively. The results showed enhanced dye degradation up to 97% within 140 min of test and antibacterial properties against gram-positive and gram-negative bacteria by the SBS NFs as compared to 80% degradation for the single nanofibers (SNFs) which had both ZnO NPs and Ag NPs but in a random orientation. SBS NFs filter (ZA-3) also exhibited a high filtration efficiency (80%) comparable to the lower 72% for SNFs filter. We believe that the as-modified electrospinning setup can be easily extended to prepare a new generation of nanofibers for a variety of applications such as biomedical, filtration, oil/water separation, and so on.
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•A multifunctional membrane composed of side by side nanofibers is presented.•Proposed the air filter with enhanced antibacterial and photocatalytic ability.•ZnO NPs was accommodated onto one side of the fiber while Ag NPs onto other side.•Side by side nanofibrous membrane had high air filtration.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
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