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The hierarchical Cu2 S@NC@MoS3 heterostructures have been firstly constructed by the high-capacity MoS3 and high-conductive N-doped carbon to co-decorate the Cu2 S hollow nanospheres. During the heterostructure, the middle N-doped carbon layer as the linker facilitates the uniform deposition of MoS3 and enhances the structural stability and electronic conductivity. The popular hollow/porous structures largely restrain the big volume changes of active materials. Due to the cooperative effect of three components, the new Cu2 S@NC@MoS3 heterostructures with dual heterogenous interfaces and small voltage hysteresis for sodium ion storage display a high charge capacity (545 mAh g-1 for 200 cycles at 0.5 A g-1 ), excellent rate capability (424 mAh g-1 at 15 A g-1 ) and ultra-long cyclic life (491 mAh g-1 for 2000 cycles at 3 A g-1 ). Except for the performance test, the reaction mechanism, kinetics analysis, and theoretical calculation have been performed to explain the reason of excellent electrochemical performance of Cu2 S@NC@MoS3 . The rich active sites and rapid Na+ diffusion kinetics of this ternary heterostructure is beneficial to the high efficient sodium storage. The assembled full cell matched with Na3 V2 (PO4 )3 @rGO cathode likewise displays remarkable electrochemical properties. The outstanding sodium storage performances of Cu2 S@NC@MoS3 heterostructures indicate the potential applications in energy storage fields.
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Considering the advantages of MOF-based, CdSe-based, and rGO-based materials, CdSe nanoparticles encapsulated with rGO (CdSe@rGO) were synthesized by a metal-organic framework derived method. CdSe nanoparticles encapsulated with rGO can effectively tolerate volume expansion and improve electrical conductivity, leading to excellent cycling stability (396 mAh g-1at 0.3 A g-1after 200 cycles, 311 mAh g-1at 0.5 A g-1after 500 cycles), and rate performance (562 mAh g-1at 0.1 A g-1and 122.2 mAh g-1at 4 A g-1) for lithium-ion storage. This strategy for preparing metal selenides protected by carbon layers can be extended to the design of other high-performance materials.
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ZnSe is regarded as a promising anode material for energy storage due to its high theoretical capacity and environment friendliness. Nevertheless, it is still a significant challenge to obtain superior electrode materials with stable performance owing to the serious volume change and aggregation upon cycling. Herein, a willow-leaf-like nitrogen-doped carbon-coated ZnSe (ZnSe@NC) composite synthesized through facile solvothermal and subsequent selenization process is beneficial to expose more active sites and facilitate the fast electron/ion transmission. These merits significantly enhance the electrochemical performances of ZnSe@NC for sodium-ion batteries (SIBs) and potassium-ion batteries (PIBs). The obtained ZnSe@NC exhibits outstanding rate performance (440.3 mAh g-1 at 0.1 A g-1 and 144.4 mAh g-1 at 10 A g-1 ) and ultralong cycle stability (242.2 mAh g-1 at 8.0 A g-1 even after 3200 cycles) for SIBs. It is noted that 106.5 mAh g-1 can be retained after 550 cycles and 71.4 mAh g-1 is still remained after 1500 cycles at 200 mA g-1 when applied as anode for PIBs, indicating good cycle stability of the electrode. The possible electrochemical mechanism and the ionic diffusion kinetics of the ZnSe@NC are investigated using ex situ X-ray diffraction, high-resolution transmission electron microscopy, and a series of electrochemical analyses.
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The large volume variations of tin-based oxides hinder their extensive application in the field of lithium-ion batteries (LIBs). In this study, structure design, hybrid fabrication, and carbon-coating approaches have been simultaneously adopted to address these shortcomings. To this end, uniform mesoporous NiO/SnO2 @rGO, Ni-Sn oxide@rGO, and SnO2 @rGO nanosphere composites have been selectively fabricated. Among them, the obtained NiO/SnO2 @rGO composite exhibited a high capacity of 800â mAh g-1 at 1000â mA g-1 after 400 cycles. The electrochemical mechanism of NiO/SnO2 as an anode for LIBs has been preliminarily investigated by ex situ XRD pattern analysis. Furthermore, an NiO/SnO2 @rGO-LiCoO2 lithium-ion full cell showed a high capacity of 467.8â mAh g-1 at 500â mA g-1 after 100 cycles. Notably, the NiO/SnO2 @rGO composite also showed good performance when investigated as an anode for sodium-ion batteries (SIBs). It is believed that the unique mesoporous nanospherical framework, synergistic effects between the various components, and uniform rGO wrapping of NiO/SnO2 shorten the Li+ ion diffusion pathways, maintain sufficient contact between the active material and the electrolyte, mitigate volume changes, and finally improve the electrical conductivity of the electrode.
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OBJECTIVE: Severe traumatic shock is one of the leading causes of death in young adults. A large number of studies have shown that effective volumetry resuscitation on the basis of controlled injury can not only increase the success rate of early resuscitation but also reduce systemic inflammatory response and improve the cure rate of severe traumatic shock. The study explored the effects of hydroxyethyl starch (HES) on the survival rate, lymphocyte function and proliferation of rats with traumatic shock, and the potential mechanisms. METHODS: Traumatic shock was constructed in rats as experimental model, and liquid resuscitation was performed using HES and lactated Ringer's (LR). 24-h mortality was recorded, and lymphocytes were isolated. The expressions of signaling pathway factors was detected by qPCR and Western blot. ELISA was performed to determine the expression of interleukin 6 (IL-6) and tumor necrosis factor-α (TNF-α) in cell supernatant. RESULTS: HES for fluid resuscitation augmented the survival of traumatic shock rats, upregulated the expressions of MEK and ERK1/2, and downregulated the expressions of IL-6 and TNF-α. However, inhibition of ERK signaling pathway reversed the effect of HES on the immune improvement and the 24-h survival rate of the traumatic shock rats (P < 0.05). CONCLUSION: HES could exert the anti-inflammatory effects on lymphocytes by mediating the phosphorylation of proteins of the ERK signaling pathway. HSE demonstrated a high efficacy in effectively treating traumatic shock, thus could be used in clinical practice.
Assuntos
Derivados de Hidroxietil Amido/uso terapêutico , Ressuscitação/métodos , Choque Traumático/terapia , Animais , Apoptose , Proliferação de Células , Células Cultivadas , Biologia Computacional , Modelos Animais de Doenças , Hidratação/métodos , Derivados de Hidroxietil Amido/administração & dosagem , Interleucina-6/metabolismo , Linfócitos/imunologia , Linfócitos/metabolismo , Linfócitos/patologia , Sistema de Sinalização das MAP Quinases , Masculino , Prognóstico , Ratos , Ratos Sprague-Dawley , Choque Traumático/metabolismo , Choque Traumático/patologia , Fator de Necrose Tumoral alfa/metabolismoRESUMO
To date, the fabrication of advanced anode materials that can accommodate both Na+ and K+ storage is still very challenging. Herein, we developed a facile solvothermal and subsequent annealing process to synthesize SnS2/RGO composite, in which SnS2 nanosheets are bonded on RGO, and investigated their potential as anodes for Na+ and K+ storage. When used as an anode in SIBs, the as-prepared SnS2/RGO displays preeminent performance (581 mAh g-1 at 0.5 A g-1 after 80 cycles), which is a significant improvement compared with pure SnS2. More encouragingly, SnS2/RGO also exhibits good cycling stability (130 mAh g-1 at 0.3 A g-1 after 300 cycles) and excellent rate capability (520.8 mAh g-1 at 0.05 A g-1 and 281.4 mAh g-1 at 0.5 A g-1) when used as anode for PIBs. The well-engineered structure not only guarantees the fast electrode reaction kinetics, but also ensures superior pseudocapacitance contribution during repeated cycles, which has been proved by kinetic analysis.
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Cobalt sulfides are attractive as intriguing candidates for anodes in SIBs and LIBs owing to their unique chemical and physical properties. In this study, a precursor of Co1-xS with a uniform and hollow nanospherical architecture is obtained with a high yield via a mild solvothermal method in the presence of 2-methylimidazole at first. Then, Co1-xS, Co1-xS/C (ultrafine Co1-xS nanoparticles embedded in the shells of the nitrogen-doped porous carbon hollow nanosphere), and Co1-xS@C (Co1-xS nanoparticles entirely covered by an external amorphous carbon layer) were selectively fabricated via direct calcination or PPy coating & calcination of the obtained precursor. Co1-xS/C shows best electrochemical performance than the other two materials as anodes for sodium-ion batteries (SIBs). Besides the excellent rate performance, a high reversible discharge capacity of 320 mA g-1 can be retained after 130 cycles at 1 A g-1. The impressive performance may be attributed to the unique structure, higher conductivity, and more active sites of Co1-xS/C. In addition, 559 mA h g-1 was maintained after 100 cycles at 500 mA g-1 when the Co1-xS/C composite was applied as an anode in lithium-ion batteries (LIBs). The high reversible capacity, excellent cycle stability combined with the facile synthesis procedure render Co1-xS/C a prospective anode material for rechargeable batteries.
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The data presented in this article are related to the research article entitled "Sandwich-like Ni2P Nanoarray/Nitrogen-Doped Graphene Nanoarchitecture as a High-Performance Anode for Sodium and Lithium Ion Batteries (Dong et al., 2018)". This work shows the morphology and structural of Ni2P/NG/Ni2P and the electrochemial performance of Ni2P/NG/Ni2P.
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Nickle sulfides as promising anode materials for sodium-ion batteries have attracted tremendous attention owing to their large specific capacity and good electrical conductivity. However, the relative large volume changes during the sodiation/desodiation process usually result in a fast capacity decay, poor cycling stability, and sluggish electrode kinetics which hinder their practical applications. Herein, NiS1.03 porous hollow spheres (NiS1.03 PHSs) and porous NiS1.03 hollow cages (NiS1.03 PHCs) with high yield are designed and selectively fabricated via a simple solvothermal and subsequent annealing approach. The obtained NiS1.03 PHSs display long-term cycling stability (127 mAh g-1 after 6000 cycles at 8 A g-1) and excellent rate performance (605 mAh g-1 at 1 A g-1 and 175 mAh g-1 at 15 A g-1). NiS1.03 PHCs also show high rate capability and outstanding cycling stability. In addition, the analyses results of in situ and ex situ XRD patterns and HRTEM images reveal the reversible Na-ion conversion mechanism of NiS1.03. It is also worth noting that the NiS1.03 PHSs//FeFe(CN)6 full cell is successfully assembled and exhibits an initial reversible capacity of 460 mAh g-1 at 0.5 A g-1, which further evidence that NiS1.03 is a kind of prospective anode material for SIBs.
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Two multifunctional metal-organic frameworks (MOFs) with the same coordination mode, [Co(L)(H2O)]n·2nH2O [defined as "Co(L) MOF"] and [Cd(L)(H2O)]n·2nH2O [defined as "Cd(L) MOF"] (L = 5-aminoisophthalic acid) have been fabricated via a simple and versatile scalable solvothermal approach at 85 °C for 24 h. The relationship between the structure of the electrode materials (especially the coordination water and different metal ions) and the electrochemical properties of MOFs have been investigated for the first time. And then the possible electrochemical mechanisms of the electrodes have been studied and proposed. In addition, MOFs/RGO hybrid materials were prepared via ball milling, which demonstrated better electrochemical performances than those of individual Co(L) MOF and Cd(L) MOF. For example, when Co(L) MOF/RGO was applied as anode for sodium ion batteries (SIBs), it retained 206 mA h g-1 after 330 cycles at 500 mA g-1 and 1185 mA h g-1 could be obtained after 50 cycles at 100 mA g-1 for lithium-ion batteries (LIBs). The high-discharge capacity, excellent cyclic stability combined with the facile synthesis procedure enable Co(L) MOF- and Cd(L) MOF-based materials to be prospective anode materials for SIBs and LIBs.