RESUMEN
Single-atom catalysts (SACs) have been increasingly explored in lithium-sulfur (Li-S) batteries to address the issues of severe polysulfide shuttle effects and sluggish redox kinetics. However, the structure-activity relationship between single-atom coordination structures and the performance of Li-S batteries remain unclear. In this study, a P, S co-coordination asymmetric configuration of single atoms is designed to enhance the catalytic activity of Co central atoms and promote d-p orbital hybridization between Co and S atoms, thereby limiting polysulfides and accelerating the bidirectional redox process of sulfur. The well-designed SACs enable Li-S batteries to demonstrate an ultralow capacity fading rate of 0.027% per cycle after 2000 cycles at a high rate of 5 C. Furthermore, they display excellent rate performance with a capacity of 619 mAh g-1 at an ultrahigh rate of 10 C due to the efficient catalysis of CoSA-N3PS. Importantly, the assembled pouch cell still retains a high discharge capacity of 660 mAh g-1 after 100 cycles at 0.2 C and provides a high areal capacity of 4.4 mAh cm-2 even with a high sulfur loading of 6 mg cm-2. This work demonstrates that regulating the coordination environment of SACs is of great significance for achieving state-of-the-art Li-S batteries.
RESUMEN
Lithium-sulfur (Li-S) batteries present significant potential for next-generation high-energy-density devices. Nevertheless, obstacles such as the polysulfide shuttle and Li-dendrite growth severely impede their commercial production. It is still hard to eliminate gaps between individual particles on separators that serve as potential conduits for polysulfide shuttling. Herein, the synthesis of a nanoscale thickness and defect-free cross-linked polyamide (PA) layer on a polypropylene (PP) separator is presented through in situ polymerization. The PA modification layer can effectively impede the diffusion of polysulfides with a thickness of only 1.5 nm, as evidenced by the results of cyclic voltammetry (CV) and time-of-flight (TOF) testing. Therefore, the Li/Li symmetric battery assembled with the functional separator exhibits an overpotential of merely 12 mV after 1000 h of cycling under test conditions of 1 mA cm-2-1 mAh cm-2. Furthermore, the capacity degradation rate of the Li-S battery is only 0.06% per cycle over 450 cycles at 1 C, while the Li-S pouch cell retains 87.63% of its capacity after 50 cycles. This work will significantly advance the preparation and application of molecules in Li-S batteries, and it will also stimulate further research on defect-free modification of separators.
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Lithium-sulfur batteries (LSBs) are considered as promising candidates in the next generation of high energy density devices. However, the serious shuttle effect, irreversible dendrite growth of Li metal anode, and the potential safety hazard impede the practical application of LSBs. Herein, a novel homogeneous Janus membrane based on functionalized MOFs crosslinked by aramid nanofibers is designed and synthesized to simultaneously solve the above challenges in quasi-solid-state LSBs. The aramid nanofibers with good mechanical properties and thermal stability act as a homogeneous scaffold to crosslink the MOF particles with different ligands on both sides and this Janus membrane upgrades the stability and safety on both the cathode and anode. Specifically, the amino ligand-decorated MOFs contribute to homogenize Li-ion flux and stabilize the lithium anode, and the sulfonic ligand-decorated MOFs effectively suppress the shuttle effect by the dual effects of chemical adsorption and electrostatic repulsion. The quasi-solid-state LSBs assembled with this homogeneous Janus membrane deliver excellent rate performance and cycling stability. Moreover, it exhibits a high initial capacity of 923.4 mAh g-1 at 1 C at 70 °C, and 697.3 mAh g-1 is retained after 100 cycles, indicating great potential for its application in high-safety LSBs.
RESUMEN
Lean-lithium metal batteries represent an advanced version of the anode-free lithium metal batteries, which can ensure high energy density and cycling stability while addressing the safety concerns and the loss of energy density caused by excessive lithium metal. Herein, a mechanically robust carbon nanotube framework current collector with gradient lithiophilicity is constructed for a lean-lithium metal battery. Using the physical vapor deposition method, precise prelithiation of a carbon nanotube framework is achieved, eliminating its irreversible capacity, retaining the porous structure in the framework, and inducing the gradient lithiophilicity formation due to spontaneous lithium ion diffusion. The lithiophilic gradient and three-dimensional porous structure are characterized by time-of-flight secondary ion mass spectrometry (TOF-SIMS), scanning transmission electron microscopy (STEM), and corresponding electron energy loss spectroscopy (EELS), which enables the preferential deposition of lithium ions at the bottom of the carbon nanotube framework, thereby avoiding lithium losses associated with dead lithium. As a result, in the LiFePO4 full cell with an ultralow N/P ratio of 0.15, the initial Coulombic efficiency increases from 77.75 to 95.07%. Collaborating synergistically with the ultrathin (1.5 µm) lithium metal, serving as a gradual lithium supplement, the full cell with an N/P ratio of 1.43 demonstrates an 86% capacity retention after 500 cycles at 1C, far surpassing the copper-based counterparts (0.9%).
RESUMEN
The strategic formulation of a compatible electrolyte plays a pivotal role in extending the longevity of lithium-metal batteries (LMBs). Here, we present findings on a partially fluorinated electrolyte distinguished by a subdued solvation affinity towards Li+ ions and a concentrated anion presence within the primary solvation layer. This distinctive solvation arrangement redirects the focal points of reactions from solvent molecules to anions, facilitating the predominant involvement of anions in the creation of a LiF-enriched solid-electrolyte interphase (SEI). Electrochemical assessments showcase effective Li+ transport kinetics, diminished overpotential polarization for Li nucleation (28â mV), and prolonged cycling durability in Li||Li cells employing the partially fluorinated electrolyte. When tested in Li||NCM811 cells, the designed electrolyte delivers a capacity retention of 89.30 % and exhibits a high average Coulombic efficiency of 99.80 % over 100 cycles with a charge-potential cut-off of 4.6â V vs. Li/Li+ under the current density of 0.4C. Furthermore, even at a current density of 1C, the cells maintain 81.90 % capacity retention and a high average Coulombic efficiency of 99.40 % after 180 cycles. This work underscores the significance of weak-solvation interaction in partially fluorinated electrolytes and highlights the crucial role of solvent structure in enabling the long-term stability and high-energy density of LMBs.
RESUMEN
Solid-state batteries based on lithium metal anodes are expected to meet safety challenges while maintaining a high energy density. One major challenge lies in the fast interface degradation between the electrolyte and the lithium metal. Herein, we propose a quasi-3D interphase on a garnet solid-state electrolyte (SSE) by introducing lithiophilic nanotrenches. The nanotrenches created by the lithiophilic nanowire array can induce the superfilling of lithium metal into the nanotrenches, resulting in a low interfacial resistance (4 Ω cm2). Moreover, the embedded lithium metal anode optimizes the lithium deposition/stripping behavior not limited at the Li-SSE interface (â¼1-10 nm) but extended into the bulk lithium anode (â¼10 µm), realizing a high critical current density of 1.8-2.0 mA cm-2 at room temperature (RT). The embedded lithium metal anode is further applied in Li||LiFePO4 solid-state batteries, demonstrating a high reversible areal capacity of â¼3.0 mAh cm-2 at RT.
RESUMEN
Lithium-sulfur battery is the most promising candidate for the next generation of rechargeable batteries because of the high energy density. However, the severe shuttle effect of lithium polysulfides (LiPSs) and degradation of the lithium anode during cycling are significant issues that hinder the practical application of lithium-sulfur batteries. Herein, monodispersed metal-organic framework (MOF)-modified nanofibers are prepared as building blocks to construct both a separator and a composite polymer electrolyte in lithium-sulfur systems. This building block possesses the intrinsic advantages of good mechanical properties, thermal stability, and good electrolyte affinity. MOFs, grown continuously on the monodispersed nanofibers, can effectively adsorb LiPSs and play a key role in regulating the nucleation and stripping/plating process of the lithium anode. When assembled into the separator, the symmetric battery remains stable for 2500 h at a current density of 1 mA cm-2, and the lithium-sulfur full cell shows improved electrochemical performance. In order to improve the safety property, the composite polymer electrolyte is prepared with the MOF-modified nanofiber as the filler. The quasi-solid-state symmetric battery remains stable for 3000 h at a current density of 0.1 mA cm-2, and the corresponding lithium-sulfur cell can cycle 800 times at 1 C with a capacity decay rate of only 0.038% per cycle.
RESUMEN
Lithium metal is an ideal anode for high-energy-density batteries. However, the low Coulomb efficiency and the generation of dendrites pose a significant limitation to its practical application, while the excess lithium in the battery also generates serious safety concerns. Herein, a layer-by-layer optimized multilayer structure integrating an artificial solid electrolyte interphase (LiF) layer, a lithiophilic (LixAu alloy) layer, and a lithium compensation layer is reported for a lean-lithium metal battery, where each layer acts synergistically to stabilize the lithium deposition behaviors and enhances the cycling performance of the battery. The optimized anode could effectively induce homogeneous reversible lithium deposition under the synergistic effect of multilayer films and keep the integrity of the morphological structure unbroken during the deposition. The presence of the lithium compensation layer allows the half-cell to have a high initial CE of 158.9%, and the action of the LiF layer and lithiophilic layer maintains an average CE of 98.8% over 160 cycles, which further demonstrates the stability of the structure. As a result, when combined with LiFePO4 cathode, an initial capacity of 148 mAh g-1 and a retention rate of 97.5% over 130 cycles were achieved.
RESUMEN
Rechargeable lithium-sulfur (Li-S) batteries have aroused great attention due to their high energy density and low cost. However, Li-S batteries suffer from rapid capacity decay owing to the shuttle effect of the intermediate polysulfides. To tackle this issue, functional separators with the ability to absorb polysulfides play a vital role to block them from passing through the separator. Herein, an ultrathin and lightweight layer of graphene oxide (GO) loaded with Co phthalocyanine (CoPc) is fabricated on a polypropylene (PP) separator. The thickness of CoPc@GO is about 200 nm with a low areal mass of 22 µg cm-2. CoPc is uniformly dispersed on GO sheets through π-π interactions, which inhibits the shuttle effect and facilitates the conversion of the intermediate polysulfides. In consequence, the battery with a CoPc@GO-PP separator exhibits good cycling stability with a low-capacity decay rate of 0.076% per cycle at 1 C over 400 cycles and a high specific capacity of 919 mA h g-1 after 250 cycles at 0.5 C.
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BACKGROUND AND AIMS: Sleep disturbances are a severe problem among patients with Alzheimer's disease (AD). By evaluating sleep quality in mild-to-moderate AD patients, this study aimed to assess the effects of multi-disciplinary team (MDT) in reducing the incidence of adverse reactions of AD patients. The reduction in the incidence of adverse reactions to predict multi-disciplinary team (MDT) treatment effects. METHODS AND RESULTS: This study included 60 mild-to-moderate AD patients with sleep problems when hospitalized in Huzhou Third Municipal Hospital. The patients were randomly distributed into two groups, routine and MDT treatments. The cognitive functions, sleep conditions, and psycho-behavioral symptoms were compared between both the groups. Cognitive function declined significantly between pretherapy and follow-up in the routine treatment group (MMSE: t = -7.961, P < 0.001; MoCA: t = -4.672, P < 0.001). There was a significant decline in drowsiness in the MDT group compared to that in the routine treatment group (χ2 = 4.320, P = 0.038). Sleep quality improved significantly during the follow-up in the MDT treatment group (t = 6.098, P < 0.001). The results of the Hamilton Depression Scale (HAMD) and Hamilton Anxiety Scale (HAMA) among family caregivers (FCGs) demonstrated that MDT treatment could alleviate caregivers' depression (t = -2.867, P = 0.042), and routine treatment can worsen their anxiety (t = 3.258, P = 0.003). CONCLUSION: The MDT treatment method as an effective and meaningful therapy can help mitigate the suffering of patients with AD and FCGs.
Asunto(s)
Enfermedad de Alzheimer , Trastornos Mentales , Trastornos del Sueño-Vigilia , Enfermedad de Alzheimer/complicaciones , Cuidadores , Humanos , Sueño , Trastornos del Sueño-Vigilia/epidemiología , Trastornos del Sueño-Vigilia/etiología , Trastornos del Sueño-Vigilia/terapiaRESUMEN
The identification and lead optimization of a series of pyrazolo[3,4-d]pyridazinone derivatives are described as a novel class of potent irreversible BTK inhibitors, resulting in the discovery of compound 8. Compound 8 exhibited high potency against BTK kinase and acceptable PK profile. Furthermore, compound 8 demonstrated significant in vivo efficacy in a mouse-collagen-induced arthritis (CIA) model.