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1.
J Colloid Interface Sci ; 674: 805-812, 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38955011

RESUMO

Lithium-sulfur (Li-S) batteries represent the most promising next-generation energy storage systems because of their high theoretical specific capacity and energy density. However, the severe shuttle effect and volume expansion of sulfur cathodes have impeded their commercial viability. Hence, accelerating the conversion of lithium polysulfides (LiPSs) is crucial for achieving efficient Li-S batteries. In this study, we employ a straightforward electrostatic self-assembly method to coat ultra-thin MXene nanosheets onto a S@MnO2 core-shell structure, resulting in a highly conductive three-dimensional network. This unique structure not only suppresses the diffusion of LiPSs but also accelerates electron and ion transfer, ensuring a rapid and efficient conversion of LiPSs. The CV curves of symmetrical cells and the Li2S deposition curves demonstrate a significant improvement in the catalytic performance of batteries with S@MnO2@MXene. The capacity of Li-S batteries achieved an impressive 842 mAh/g at the current density of 1C, with a minimal capacity decay of only 0.84 mAh/g per cycle within 500 cycles. Additionally, increasing the sulfur loading mass to 5.88 mg cm-2 resulted in an areal capacity of 6.33 mAh cm-2, demonstrating practical application potential.

2.
Artigo em Inglês | MEDLINE | ID: mdl-38985897

RESUMO

The commercial viability of emerging lithium-sulfur batteries (LSBs) remains greatly hindered by short lifespans caused by electrically insulating sulfur, lithium polysulfides (Li2Sn; 1 ≤ n ≤ 8) shuttling, and sluggish sulfur reduction reactions (SRRs). This work proposes the utilization of a hybrid composed of sulfiphilic MoS2 and mayenite electride (C12A7:e-) as a cathode host to address these challenges. Specifically, abundant cement-based C12A7:e- is the most stable inorganic electride, possessing the ultimate electrical conductivity and low work function. Through density functional theory simulations, the key aspects of the MoS2/C12A7:e- hybrid including electronic properties, interfacial binding with Li2Sn, Li+ diffusion, and SRR have been unraveled. Our findings reveal the rational rules for MoS2 as an efficient cathode host by enhancing its mutual electrical conductivity and surface polarity via MoS2/C12A7:e-. The improved electrical conductivity of MoS2 is attributed to the electron donation from C12A7:e- to MoS2, yielding a semiconductor-to-metal transition. The resultant band positions of MoS2/C12A7:e- are well matched with those of conventional current-collecting materials (i.e., Cu and Ni), electrochemically enhancing the electronic transport. The accepted charge also intensifies MoS2 surface polarity for attracting polar Li2Sn by forming stronger bonds with Li2Sn via ionic Li-S bonds than electrolytes with Li2Sn, thereby preventing polysulfide shuttling. Importantly, MoS2/C12A7:e- not only promotes rapid reaction kinetics by reducing ionic diffusion barriers but also lowers the Gibbs free energies of the SRR for effective S8-to-Li2S conversion. Beyond the reported applications of C12A7:e-, this work highlights its functionality as an electrode material to boost the efficiency of LSBs.

3.
Adv Sci (Weinh) ; : e2402389, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38867385

RESUMO

Despite the very high theoretical energy density, Li-S batteries still need to fundamentally overcome the sluggish redox kinetics of lithium polysulfides (LiPSs) and low sulfur utilization that limit the practical applications. Here, highly active and stable cathode, nitrogen-doped porous carbon nanotubes (NPCTs) decorated with NixCo1-xS2 nanocrystals are systematically synthesized as multi-functional electrocatalytic materials. The nitrogen-doped carbon matrix can contribute to the adsorption of LiPSs on heteroatom active sites with buffering space. Also, both experimental and computation-based theoretical analyses validate the electrocatalytic principles of co-operational facilitated redox reaction dominated by covalent-site-dependent mechanism; the favorable adsorption-interaction and electrocatalytic conversion of LiPSs take place subsequently by weakening sulfur-bond strength on the catalytic NiOh 2+-S-CoOh 2+ backbones via octahedral TM-S (TM = Ni, Co) covalency-relationship, demonstrating that fine tuning of CoOh 2+ sites by NiOh 2+ substitution effectively modulates the binding energies of LiPSs on the NixCo1-xS2@NPCTs surface. Noteworthy, the Ni0.261Co0.739S2@NPCTs catalyst shows great cyclic stability with a capacity of up to 511 mAh g-1 and only 0.055% decay per cycle at 5.0 C during 1000 cycles together with a high areal capacity of 2.20 mAh cm-2 under 4.61 mg cm-2 sulfur loading even after 200 cycles at 0.2 C. This strategy highlights a new perspective for achieving high-energy-density Li-S batteries.

4.
Nanomaterials (Basel) ; 14(12)2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38921866

RESUMO

Intensive increases in electrical energy storage are being driven by electric vehicles (EVs), smart grids, intermittent renewable energy, and decarbonization of the energy economy. Advanced lithium-sulfur batteries (LSBs) are among the most promising candidates, especially for EVs and grid-scale energy storage applications. In this topical review, the recent progress and perspectives of practical LSBs are reviewed and discussed; the challenges and solutions for these LSBs are analyzed and proposed for future practical and large-scale energy storage applications. Major challenges for the shuttle effect, reaction kinetics, and anodes are specifically addressed, and solutions are provided on the basis of recent progress in electrodes, electrolytes, binders, interlayers, conductivity, electrocatalysis, artificial SEI layers, etc. The characterization strategies (including in situ ones) and practical parameters (e.g., cost-effectiveness, battery management/modeling, environmental adaptability) are assessed for crucial automotive/stationary large-scale energy storage applications (i.e., EVs and grid energy storage). This topical review will give insights into the future development of promising Li-S batteries toward practical applications, including EVs and grid storage.

5.
Small ; : e2402725, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38837316

RESUMO

Unveiling the inherent link between polysulfide adsorption and catalytic activity is key to achieving optimal performance in Lithium-sulfur (Li-S) batteries. Current research on the sulfur reaction process mainly relies on the strong adsorption of catalysts to confine lithium polysulfides (LiPSs) to the cathode side, effectively suppressing the shuttle effect of polysulfides. However, is strong adsorption always correlated with high catalysis? The inherent relationship between adsorption and catalytic activity remains unclear, limiting the in-depth exploration and rational design of catalysts. Herein, the correlation between "d-band center-adsorption strength-catalytic activity" in porous carbon nanofiber catalysts embedded with different transition metals (M-PCNF-3, M = Fe, Co, Ni, Cu) is systematically investigated, combining the d-band center theory and the Sabatier principle. Theoretical calculations and experimental analysis results indicate that Co-PCNF-3 electrocatalyst with appropriate d-band center positions exhibits moderate adsorption capability and the highest catalytic conversion activity for LiPSs, validating the Sabatier relationship in Li-S battery electrocatalysts. These findings provide indispensable guidelines for the rational design of more durable cathode catalysts for Li-S batteries.

6.
Small ; : e2401587, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38855999

RESUMO

Heterostructured materials commonly consist of bifunctions due to the different ingredients. For host material in the sulfur cathode of lithium-sulfur (Li-S) batteries, the chemical adsorption and catalytic activity for lithium polysulfides (LiPS) are important. This work obtains a Ni5P2-Ni nanoparticle (Ni5P2-NiNPs) heterostructure through a confined self-reduction method followed by an in situ phosphorization process using Al/Ni-MOF as precursors. The Ni5P2-Ni heterostructure not only has strong chemical adsorption, but also can effectively catalyze LiPS conversion. Furthermore, the synthetic route can keep Ni5P2-NiNPs inside of the nanocomposites, which have structural stability, high conductivity, and efficient adsorption/catalysis in LiPS conversion. These advantages make the assembled Li-S battery deliver a reversible specific capacity of 619.7 mAh g- 1 at 0.5 C after 200 cycles. The in situ ultraviolet-visible technique proves the catalytic effect of Ni5P2-Ni heterostructure on LiPS conversion during the discharge process.

7.
J Colloid Interface Sci ; 670: 519-529, 2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-38776687

RESUMO

The high theoretical energy density and specific capacity of lithium-sulfur (Li-S) batteries have garnered considerable attention in the prospective market. However, ongoing research on Li-S batteries appears to have encountered a bottleneck, with unresolved key technical challenges such as the significant shuttle effect and sluggish reaction kinetics. This investigation explores the catalytic efficacy of three catalysts for Li-S batteries and elucidates the correlation between their structure and catalytic impacts. The results suggest that the combined utilization of lithium-insertion technology and a proton exchange approach for δ-MnO2 can optimize its electronic structure, resulting in an optimal catalyst (H/Li inserted δ-MnO2, denoted as HLM) for the sulfur reduction reaction. The replacement of Mn sites in δ-MnO2 with Li atoms can enhance the structural stability of the catalyst, while the introduction of H atoms between transition metal layers contributes to the satisfactory catalytic performance of HLM. Theoretical calculations demonstrate that the bond length of Li2S4 adsorbed by the HLM molecule is elongated, thereby facilitating the dissociation process of Li2S4 and enhancing the reaction kinetics in Li-S batteries. Consequently, the Li-S battery utilizing HLM as a catalyst achieves a high areal specific capacity of 4.2 mAh cm-2 with a sulfur loading of 4.1 mg cm-2 and a low electrolyte/sulfur (E/S) ratio of 8 µL mg-1. This study introduces a methodology for designing effective catalysts that could significantly advance practical developments in Li-S battery technology.

8.
J Colloid Interface Sci ; 671: 653-663, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38820849

RESUMO

The application of Li-S batteries on large scale is held back by the sluggish sulfur kinetics and low synthesis efficiency of sulfur host. In addition, the preparation of catalysts that promote polysulfide redox kinetics is complex and time-consuming, reducing the cost of raw materials in Li-S. Here, a universal synthetic strategy for rapid fabrication of sulfur cathode and metal compounds nanocatalysts is reported based on microwave heating of graphene. Heat-sensitive materials can achieve rapid heating due to graphene reaching 500 ℃ within 4 s via microwave irradiation. The MoP-MoS2/rGO catalyst demonstrated in this work was synthesized within 60 s. When used for catalysts for Li-S batteries whose graphene/sulfur cathodes were also synthesized by microwave heating, enhanced catalytic effect for sulfur redox reaction was verified via experimental and DFT theoretical results. Benefiting from fast redox reaction (MoP), smooth Li+ diffusion pathways (MoS2), and large conductive network (rGO), the assembled Li-S battery with MoP-MoS2/rGO-Add@CS displays a remarkable initial specific capacity, stable lithium anode and good cycle stability (in pouch cells) using this two-pronged strategy. The work provides a practical strategy for advanced Li-S batteries toward a wide range of applications.

9.
Small ; : e2311193, 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38739093

RESUMO

LiB alloy is promising lithium (Li) metal anode material because the continuous internal LiB fiber skeleton can effectively suppress Li dendrites and structural pulverization. However, the unvalued surface states limit the practical application of LiB alloy anodes. Herein, the study examined the influence of the different exposure manners of the internal LiB fiber skeleton owing to the various surface states of the LiB alloy anode on electrochemical performance and targetedly proposed a scalable friction coating strategy to construct a lithiated fumed silica (LFS) functional layer with abundant electrochemically active sites on the surface of the LiB alloy anode. The LFS significantly suppresses the inhomogeneous interfacial electrochemical behavior of the LiB alloy anode and enables the exposure of the internal LiB fiber skeleton in a homogeneously planar manner (LFS-LiB). Thus, a 0.5 Ah LFS-LiB||LiCoO2 (LCO) pouch cell exhibits a discharge capacity retention rate of 80% after 388 cycles. Moreover, a 6.15 Ah LFS-LiB||S pouch cell with 409.3 Wh kg-1 exhibits a discharge capacity retention rate of 80% after 30 cycles. In conclusion, the study findings provide a new research perspective for Li alloy anodes.

10.
Adv Sci (Weinh) ; 11(25): e2308604, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38654467

RESUMO

As a very prospective solid-state electrolyte, Li10GeP2S12 (LGPS) exhibits high ionic conductivity comparable to liquid electrolytes. However, severe self-decomposition and Li dendrite propagation of LGPS will be triggered due to the thermodynamic incompatibility with Li metal anode. Herein, by adopting a facile chemical vapor deposition method, an artificial solid electrolyte interphase composed of Li2S is proposed as a single ionic conductor to promote the interface stability of LGPS toward Li. The good electronic insulation coupled with ionic conduction property of Li2S effectively blocks electron transfer from Li to LGPS while enabling smooth passage of Li ions. Meanwhile, the generated Li2S layer remains good interface compatibility with LGPS, which is verified by the stable Li-plating/stripping operation for over 500 h at 0.15 mA cm-2. Consequently, the all-solid-state Li-S batteries (ASSLSBs) with a Li2S layer demonstrate superb capacity retention of 90.8% at 0.2 mA cm-2 after 100 cycles. Even at the harsh condition of 90 °C, the cell can deliver a high reversible capacity of 1318.8 mAh g-1 with decent capacity retention of 88.6% after 100 cycles. This approach offers a new insight for interface modification between LGPS and Li and the realization of ASSLSBs with stable cycle life.

11.
Adv Mater ; 36(28): e2400639, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38664988

RESUMO

Lithium-sulfur (Li-S) batteries, operated through the interconversion between sulfur and solid-state lithium sulfide, are regarded as next-generation energy storage systems. However, the sluggish kinetics of lithium sulfide deposition/dissolution, caused by its insoluble and insulated nature, hampers the practical use of Li-S batteries. Herein, leaf-like carbon scaffold (LCS) with the modification of Mo2C clusters (Mo2C@LCS) is reported as host material of sulfur powder. During cycles, the dissociative Mo ions at the Mo2C@LCS/electrolyte interface are detected to exhibit competitive binding energy with Li ions for lithium sulfide anions, which disrupts the deposition behavior of crystalline lithium sulfide and trends a shift in the configuration of lithium sulfide toward an amorphous structure. Combining the related electrochemical study and first-principle calculation, it is revealed that the formation of amorphous lithium sulfides shows significantly improved kinetics for lithium sulfide deposition and decomposition. As a result, the obtained Mo2C@LCS/S cathode shows an ultralow capacity decay rate of 0.015% per cycle at a high mass loading of 9.5 mg cm-2 after 700 cycles. More strikingly, an ultrahigh sulfur loading of 61.2 mg cm-2 can also be achieved. This work defines an efficacious strategy to advance the commercialization of Mo2C@LCS host for Li-S batteries.

12.
BMC Palliat Care ; 23(1): 83, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38556869

RESUMO

BACKGROUND: Due to limited numbers of palliative care specialists and/or resources, accessing palliative care remains limited in many low and middle-income countries. Data science methods, such as rule-based algorithms and text mining, have potential to improve palliative care by facilitating analysis of electronic healthcare records. This study aimed to develop and evaluate a rule-based algorithm for identifying cancer patients who may benefit from palliative care based on the Thai version of the Supportive and Palliative Care Indicators for a Low-Income Setting (SPICT-LIS) criteria. METHODS: The medical records of 14,363 cancer patients aged 18 years and older, diagnosed between 2016 and 2020 at Songklanagarind Hospital, were analyzed. Two rule-based algorithms, strict and relaxed, were designed to identify key SPICT-LIS indicators in the electronic medical records using tokenization and sentiment analysis. The inter-rater reliability between these two algorithms and palliative care physicians was assessed using percentage agreement and Cohen's kappa coefficient. Additionally, factors associated with patients might be given palliative care as they will benefit from it were examined. RESULTS: The strict rule-based algorithm demonstrated a high degree of accuracy, with 95% agreement and Cohen's kappa coefficient of 0.83. In contrast, the relaxed rule-based algorithm demonstrated a lower agreement (71% agreement and Cohen's kappa of 0.16). Advanced-stage cancer with symptoms such as pain, dyspnea, edema, delirium, xerostomia, and anorexia were identified as significant predictors of potentially benefiting from palliative care. CONCLUSION: The integration of rule-based algorithms with electronic medical records offers a promising method for enhancing the timely and accurate identification of patients with cancer might benefit from palliative care.


Assuntos
Neoplasias , Cuidados Paliativos , Humanos , Reprodutibilidade dos Testes , Registros Eletrônicos de Saúde , Neoplasias/terapia , Mineração de Dados , Algoritmos
13.
Small ; : e2400068, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38593293

RESUMO

Lithium-sulfur (Li-S) batteries with high theoretical energy density (2600 Wh kg-1) are considered to be one of the most promising secondary batteries. However, the practical application of Li-S batteries is limited by the polysulfides shuttling and unstable lithium metal anodes. Herein, an asymmetric separator (CACNM@PP), composed of Co-Ni/MXene (CNM) on the cathode and Cu-Ag/MXene (CAM) on the anode for high-performance Li-S batteries is reported. For the cathode, CNM provides a synergistic effect by integrating Co, Ni, and MXene, resulting in strong chemical interactions and fast conversion kinetics for polysulfides. For the anode, CAM with abundant lithiophilicity active sites can lower the nucleation barrier of Li. Moreover, LiCl/LiF layers are generated in situ as an ion conductor layer during charging and discharging, inducing a uniform deposition of Li. Therefore, the assembled cells with the CACNM@PP separators harvest excellent electrochemical performance. This work provides novel insights into the development of commercially available high-energy density Li-S batteries with asymmetric separators.

14.
Bull Atmos Sci Technol ; 5(1): 2, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38586869

RESUMO

Terrestrial gamma-ray flashes (TGFs) are bursts of energetic X- and gamma-rays emitted from thunderstorms. The Atmosphere-Space Interactions Monitor (ASIM) mounted onto the International Space Station (ISS) is dedicated to measure TGFs and optical signatures of lightning; ISS LIS (Lightning Imaging Sensor) detects lightning flashes allowing for simultaneous measurements with ASIM. Whilst ASIM measures ∼300-400 TGFs per year, ISS LIS detects ∼106 annual lightning flashes giving a disproportion of four orders of magnitude. Based on the temporal evolution of lightning flashes and the spatial pattern of the constituing events, we present an algorithm to reduce the number of space-detected flashes potentially associated with TGFs by ∼ 60% and of associated LIS groups by ∼ 95%. We use ASIM measurements to confirm that the resulting flashes are indeed those associated with TGFs detected at approx. 400 km altitude and thus benchmark our algorithm preserving 70-80% of TGFs from concurrent ASIM-LIS measurements. We compare how the radiance, footprint size and the global distribution of lightning flashes of the reduced set relates to the average of all measured lightning flashes and do not observe any significant difference. Finally, we present a parameter study of our algorithm and discuss which parameters can be tweaked to maximize the reduction efficiency whilst keeping flashes associated to TGFs. In the future, this algorithm will hence be capable of facilitating the search for TGFs in a reduced set of lightning flashes measured from space.

15.
Cancer Cell Int ; 24(1): 129, 2024 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-38582841

RESUMO

BACKGROUND: The objective of this study was to determine the role and regulatory mechanism of miR-380 in cholangiocarcinoma. METHODS: The TargetScan database and a dual-luciferase reporter assay system were used to determine if LIS1 was a target gene of miR-380. The Cell Counting Kit 8 assay, flow cytometry, and Transwell assay were used to detect the effects of miR-380 and LIS1 on the proliferation, S-phase ratio, and invasiveness of HCCC-9810/HuCCT1/QBC939 cells. Western blotting was used to determine the effect of miR-380 on MMP-2/p-AKT. Immunohistochemistry detected the regulatory effect of miR-380 on the expression of MMP-2/p-AKT/LIS1. RESULTS: Expression of miR-380 in cholangiocarcinoma was decreased but expression of LIS1 was increased. LIS1 was confirmed to be a target gene of miR-380. Transfection with miR-380 mimics inhibited the proliferation, S-phase arrest, and invasion of HCCC-9810/HuCCT1/QBC939 cells, and LIS1 reversed these inhibitory effects. miR-380 inhibitor promoted proliferation, S-phase ratio, and invasiveness of HCCC-9810/HuCCT1/QBC939 cells. si-LIS1 salvaged the promotive effect of miR-380 inhibitor. Overexpression of miR-380 inhibited expression of MMP-2/p-AKT/LIS1, but miR-380 inhibitor promoted their expression. CONCLUSION: An imbalance of miR-380 expression is closely related to cholangiocarcinoma, and overexpression of miR-380 inhibits the expression of MMP-2/p-AKT by directly targeting LIS1.

16.
J Colloid Interface Sci ; 666: 322-330, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38603875

RESUMO

The commercial application of lithium-sulfur batteries is primarily impeded by the constant shuttling of soluble polysulfides and sluggish redox kinetics. Nowadays, the discovery of the heterojunction, which combines materials with diverse properties, offers a new perspective for overcoming these obstacles. Herein, a functional coating separator for the lithium-sulfur battery is designed using a MnO2-ZnS p-n heterojunction with a spontaneous built-in electric field (BIEF). The MnO2 nanowire provides suitable adsorption capacity for polysulfides, while the abundant reactive sites brought by ZnS ensure efficient conversion. Moreover, the BIEF significantly facilitates the migration of electrons and polysulfides at the MnO2-ZnS interface, enabling a smooth "adsorption-diffusion-conversion" reaction mechanism. By serving as both the adsorption module and catalytic sites, this BIEF allows batteries utilizing separators modified with MnO2-ZnS heterojunction to achieve an impressive initial capacity of 1511.1 mAh g-1 at 0.1C and maintain a capacity decay rate of merely 0.048% per cycle at 2.0C after 1000 cycles. Even when increasing sulfur loading to 9.4 mg cm-2 in lean electrolyte (5.4 µL mg-1), the battery still exhibits an ultrahigh areal capacity of 6.0 mAh cm-2 after 100 cycles.

17.
ACS Appl Mater Interfaces ; 16(15): 18937-18948, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38564761

RESUMO

The shuttle effect of soluble lithium polysulfides (LiPSs) poses a crucial challenge for commercializing lithium-sulfur batteries. The functionalization of the separator is an effective strategy for enhancing the cell lifespan through the capture and reuse of LiPSs. Herein, a novel In2O3 nanorod with an ultrathin carbon layer (In2O3@C) was coated on a polypropylene separator. The results demonstrate the adsorption and catalysis of In2O3 on polysulfides, effectively inhibiting the shuttle effect and improving the redox kinetics of LiPSs. Besides, the ultrathin carbon layer increases the reaction sites and accelerates the electrochemical reaction rate. The cell with the In2O3@C interlayer displays excellent reversibility and stability with a 0.029% capacity decay each cycle in 2000 cycles at 2C. In addition, the In2O3@C interlayer significantly improves the cell performance under high current (888.2 mA h g-1 at 2C and room temperature) and low temperature (1007.8 mA h g-1 at 0.1C and -20 °C) conditions.

18.
Nanomaterials (Basel) ; 14(8)2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38668186

RESUMO

Lithium-sulfur (Li-S) batteries with a high theoretical energy density of 2600 Wh·kg-1 are hindered by challenges such as low S conductivity, the polysulfide shuttle effect, low S reduction conversion rate, and sluggish Li2S oxidation kinetics. Herein, single-atom non-noble metal catalysts (SACs) loaded on two-dimensional (2D) vanadium disulfide (VS2) as the potential host materials for the cathode in Li-S batteries were investigated systematically by using first-principles calculations. Based on the comparisons of structural stability, the ability to immobilize sulfur, electrochemical reactivity, and the kinetics of Li2S oxidation decomposition between these non-noble metal catalysts and noble metal candidates, Nb@VS2 and Ta@VS2 were identified as the potential candidates of SACs with the decomposition energy barriers for Li2S of 0.395 eV (Nb@VS2) and of 0.162 eV (Ta@VS2), respectively. This study also identified an exothermic reaction for Nb@VS2 and the Gibbs free energy of 0.218 eV for Ta@VS2. Furthermore, the adsorption and catalytic mechanisms of the VS2-based SACs in the reactions were elucidated, presenting a universal case demonstrating the use of unconventional graphene-based SACs in Li-S batteries. This study presents a universal surface regulation strategy for transition metal dichalcogenides to enhance their performance as host materials in Li-S batteries.

19.
Aesthetic Plast Surg ; 48(13): 2465-2474, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38548959

RESUMO

BACKGROUND: Strategies minimizing surgical bleeding, including the antifibrinolytic agent tranexamic acid, play a crucial role in clinical practice to optimize overall surgical outcomes. Despite its proven efficacy in various clinical fields, there is a limited understanding regarding the use of tranexamic acid in plastic and aesthetic procedures. This study is the first investigating the effects of systemically administered tranexamic acid on postoperative blood loss and bleeding complications in fleur-de-lis abdominoplasties and apronectomies. METHODS: Patients who received 1 g tranexamic acid (n = 44) during fleur-de-lis abdominoplasty or apronectomy were retrospectively compared with those who did not (n = 44). In this context, the outcome parameters 24-h and total drain fluid production, drain time, hospital stay, absolute and relative drop in hemoglobin and hematocrit level as well as bleeding complications such as blood transfusion, hematoma puncture and evacuation were evaluated. RESULTS: Tranexamic acid significantly decreased both drainage volume in 24 h (40.5%, p = 0.0046) and total drain fluid production (42.5%, p = 0.0017). Moreover, a shorter drainage time (19.4%, p = 0.0028) and hospital stay (21.4%, p = 0.0009) were observed. The administration of tranexamic acid was also associated with a reduced postoperative decline in hemoglobin and hematocrit levels. Notably, no bleeding complications were observed in patients who received tranexamic acid, while 6 events occurred in patients without (p = 0.0262). CONCLUSION: Systemic administration of tranexamic acid effectively reduced postoperative blood loss and bleeding complications in fleur-de-lis abdominoplasties and apronectomies. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .


Assuntos
Abdominoplastia , Antifibrinolíticos , Hemorragia Pós-Operatória , Ácido Tranexâmico , Humanos , Ácido Tranexâmico/administração & dosagem , Ácido Tranexâmico/uso terapêutico , Abdominoplastia/efeitos adversos , Abdominoplastia/métodos , Feminino , Estudos Retrospectivos , Antifibrinolíticos/administração & dosagem , Antifibrinolíticos/uso terapêutico , Hemorragia Pós-Operatória/prevenção & controle , Hemorragia Pós-Operatória/etiologia , Pessoa de Meia-Idade , Masculino , Adulto , Resultado do Tratamento , Estudos de Coortes , Medição de Risco , Tempo de Internação/estatística & dados numéricos , Perda Sanguínea Cirúrgica/prevenção & controle
20.
Small ; : e2311850, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38446091

RESUMO

Lithium-sulfur (Li-S) batteries hold immense promise as next-generation energy storage due to their high theoretical energy density (2600 Wh kg⁻¹), low cost, and non-toxic nature. However, practical implementation faces challenges, primarily from Li polysulfide (LiPS) shuttling within the cathode and Li dendrite growth at the anode. Optimized electrodes/electrolytes design effectively confines LiPS to the cathode, boosting cycling performance in coin cells to up to hundreds of cycles. Scaling up to larger pouch cells presents new obstacles, requiring further research for long-term stability. A 1.45 Ah pouch cell, with optimized sulfur loading and electrolyte/sulfur ratio is developed, which delivers an energy density of 151 Wh kg-1 with 70% capacity retention up to 100 cycles. Targeting higher energy density (180 Wh kg-1 ), the developed 1Ah pouch cell exhibits 68% capacity retention after 50 cycles. Morphological analysis reveals that pouch cell failure is primarily from Li metal powdering and resulting polarization, rather than LiPS shuttling. This occurs for continuous Li ion stripping/plating during cycling, leading to dendrite growth and formation of non-reactive Li powder, especially under high currents. These issues increase ion diffusion resistance and reduce coulombic efficiency over time. Therefore, the study highlights the importance of a protected Li metal anode for achieving high-energy-dense batteries.

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