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1.
Small ; : e2312129, 2024 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-38593332

RESUMEN

Lithium (Li) metal is widely recognized as a viable candidate for anode material in future battery technologies due to its exceptional energy density. Nevertheless, the commercial Li foils in common use are too thick (≈100 µm), resulting in a waste of Li resources. Herein, by applying the vacuum evaporation plating technology, the ultra-thin Li foils (VELi) with high purity, strong adhesion, and thickness of less than 10 µm are successfully prepared. The manipulation of evaporation temperature allows for convenient regulation of the thickness of the fabricated Li film. This physical thinning method allows for fast, continuous, and highly accurate mass production. With a current density of 0.5 mA cm-2 for a plating amount of 0.5 mAh cm-2, VELi||VELi cells can stably cycle for 200 h. The maximum utilization of Li is already more than 25%. Furthermore, LiFePO4||VELi full cells present excellent cycling performance at 1 C (1 C = 155 mAh g-1) with a capacity retention rate of 90.56% after 240 cycles. VELi increases the utilization of active Li and significantly reduces the cost of Li usage while ensuring anode cycling and multiplication performance. Vacuum evaporation plating technology provides a feasible strategy for the practical application of ultra-thin Li anodes.

2.
Small ; 18(44): e2204037, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36127260

RESUMEN

All-solid-state batteries (ASSBs) with alloy anodes are expected to achieve high energy density and safety. However, the stability of alloy anodes is largely impeded by their large volume changes during cycling and poor interfacial stability against solid-state electrolytes. Here, a mechanically prelithiation aluminum foil (MP-Al-H) is used as an anode to construct high-performance ASSBs with sulfide electrolyte. The dense Li-Al layer of the MP-Al-H foil acts as a prelithiated anode and forms a 2D interface with sulfide electrolyte, while the unlithiated Al layer acts as a tightly bound current collector and ensures the structural integrity of the electrode. Remarkably, the MP-Al-H anode exhibits superior lithium conduction kinetics and stable interfacial compatibility with Li6 PS5 Cl (LPSCl) and Li10 GeP2 S12 electrolytes. Consequently, the symmetrical cells using LPSCl electrolyte can work at a high current density of 7.5 mA cm-2 and endure for over 1500 h at 1 mA cm-2 . Notably, ≈100% capacity is retained for the MP-Al-H||LPSCl||LiCoO2 full cell with high area loadings of 18 mg cm-2 after 300 cycles. This work offers a pathway to improve the interfacial and performance issues for the application of ASSBs.

3.
J Gastroenterol Hepatol ; 37(11): 2031-2038, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36066910

RESUMEN

OBJECTIVES: To understand the global incidence of the adverse events associated with fecal microbiota transplantation (FMT) in children over the past 20 years. METHODS: We searched PubMed, Web of Science, Embase, and three Chinese databases (CNKI, Wanfang, and Chongqing Weipu) for high-quality articles written over the past 20 years and made selections based on the quality standard score. The study characteristics and incidences of adverse events were extracted from each article, meta-analysis was performed using the R.3.6.3 software, and randomized-effect or fixed-effect meta-analyses were used to determine the incidence of adverse events. Subgroup analysis was performed to determine heterogeneity. RESULTS: A total of 18 articles involving 681 children were included in the analysis. The total effective rate of FMT in children was 85.75% (95% CI: 76.23-93.15%), of which the overall efficacy of FMT for the treatment of Clostridium difficile infection was 91.22% (95% CI: 83.49-96.68%) and the overall adverse event rate was 28.86% (95% CI: 19.56-39.15%), with a mild to moderate adverse event rate of 27.72% (95% CI: 17.86-38.83%) and a severe adverse event rate of 0.90% (95% CI: 0.33-1.76%). The most common mild to moderate adverse events were as follows: bellyache, 14.02% (95% CI: 5.43-25.77%); diarrhea, 7.75% (95% CI: 2.69-15.11%); and bloating, 7.36% (95% CI: 1.79-16.28%). Other adverse events included fever, 2.34%; vomiting, 3.12%; nausea, 1.50%; hematochezia, 2.30%; anorexia, 1.94%; and fatigue, 0.03%. The only death reported was in a study from China, in which the patient died of sepsis and liver failure 4 weeks after FMT. The other serious adverse event was an immunodeficiency patient with severe hematochezia. Another study in the United States described seven serious adverse events including one death that was not considered to be related to FMT; however, they did not describe the events in detail. There was no difference in the incidence of adverse events between the upper and lower gastrointestinal tracts (OR = 0.61, 95% CI: 0.02-15.42, P = 0.76). CONCLUSION: Adverse events related to FMT in children are mostly mild to moderate, of short duration, and self-limiting. Therefore, the use of FMT in children is safe and worthy of widespread promotion.


Asunto(s)
Infecciones por Clostridium , Enterocolitis Seudomembranosa , Niño , Humanos , Trasplante de Microbiota Fecal/efectos adversos , Incidencia , Infecciones por Clostridium/etiología , Hemorragia Gastrointestinal/etiología , Resultado del Tratamiento
4.
Phys Chem Chem Phys ; 24(48): 29512-29519, 2022 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-36448472

RESUMEN

The solvation of cations is one of the important factors that determine the properties of electrolytes. Rational solvation structures can effectively improve the performance of various electrochemical energy storage devices. Water-in-Salt (WIS) electrolytes with a wide electrochemically stable potential window (ESW) have been proposed to realize high cell potential aqueous electrochemical energy storage devices relying on the special solvation structures of cations. The ratio of H2O molecules participating in the primary solvation structure of a cation (a cation hydration ratio) is the key factor for the kinetics and thermodynamics of the WIS electrolytes under an electric field. Here, acetates with different cations were used to prepare WIS electrolytes. And, the effect of different cation hydration ratios on the properties of WIS electrolytes was investigated. Various WIS electrolytes exhibited different physicochemical properties, including the saturated concentration, conductivity, viscosity, pH values and ESW. The WIS electrolytes with a low cation hydration ratio (<100%, an NH4-based WIS electrolyte) or a high cation hydration ratio (>100%, a K-based WIS electrolyte and a Cs-based WIS electrolyte) exhibit more outstanding conductivity or a wide ESW, respectively. SCs constructed from active carbon (AC) and these WIS electrolytes exhibited distinctive electrochemical properties. A SC with an NH4-based WIS electrolyte was characterized by higher capacity and better rate capability. SCs with a K-based WIS electrolyte and a Cs-based WIS electrolyte were characterized by a wider operating cell potential, higher energy density and better ability to suppress self-discharge and gas production. These results show that a WIS electrolyte with a low cation hydration ratio or a high cation hydration ratio is suitable for the construction of power-type or energy-type aqueous SCs, respectively. This understanding provides the foundation for the development of novel WIS electrolytes for the application of SCs.

5.
Int J Mol Sci ; 23(17)2022 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-36077400

RESUMEN

The trinitromethyl moiety is a useful group for the design and development of novel energetic compounds with high nitrogen and oxygen content. In this work, by using an improved nitration method, the dinitromethyl precursor was successfully nitrated to the trinitromethyl product (2), and its structure was thoroughly characterized by FTIR, NMR, elemental analysis, differential scanning calorimetry, and single-crystal X-ray diffraction. Compound 2 has a high density (1.897 g cm-3), high heat of formation (984.8 kJ mmol-1), and a high detonation performance (D: 9351 m s-1, P: 37.46 GPa) that may find useful applications in the field of high energy density materials.


Asunto(s)
Sustancias Explosivas , Oxadiazoles , Cristalografía por Rayos X , Sustancias Explosivas/química , Nitrógeno , Oxadiazoles/química , Oxígeno/química
6.
Molecules ; 26(24)2021 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-34946612

RESUMEN

The nitration of chitin monomer in a mixture of nitric acid and acetic anhydride was conducted and a highly nitrated (3R,4R,6R)-3-acetamido-6-((nitrooxy)methyl)tetrahydro-2H-pyran-2,4,5-triyl trinitrate (1) was obtained. Its structure was fully characterized using infrared spectroscopy, NMR spectroscopy, elemental analysis, and X-ray diffraction. Compound 1 possesses good density (ρ: 1.721 g·cm-3) and has comparable detonation performance (Vd: 7717 m·s-1; P: 25.6 GPa) to that of nitrocellulose (NC: Vd: 7456 m·s-1; P: 23 GPa; Isp = 239 s) and microcrystalline nitrocellulose (MCNC; Vd: 7683 m·s-1; P: 25 GPa; Isp = 250 s). However, Compound 1 has much lower impact sensitivity (IS: 15 J) than the regular nitrocellulose (NC; IS: 3.2 J) and MCNC (IS: 2.8 J). Compound 1 was calculated to exhibit a good specific impulse (Isp: 240 s), which is comparable with NC (Isp: 239 s) and MCNC (Isp: 250 s). By replacing the nitrocellulose with Compound 1 in typical propellants JA2, M30, and M9, the specific impulse was improved by up to 4 s. These promising properties indicate that Compound 1 has a significant potential as an energetic component in solid propellants.

7.
BMC Bioinformatics ; 21(1): 334, 2020 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-32723290

RESUMEN

BACKGROUND: Shotgun metagenomics based on untargeted sequencing can explore the taxonomic profile and the function of unknown microorganisms in samples, and complement the shortage of amplicon sequencing. Binning assembled sequences into individual groups, which represent microbial genomes, is the key step and a major challenge in metagenomic research. Both supervised and unsupervised machine learning methods have been employed in binning. Genome binning belonging to unsupervised method clusters contigs into individual genome bins by machine learning methods without the assistance of any reference databases. So far a lot of genome binning tools have emerged. Evaluating these genome tools is of great significance to microbiological research. In this study, we evaluate 15 genome binning tools containing 12 original binning tools and 3 refining binning tools by comparing the performance of these tools on chicken gut metagenomic datasets and the first CAMI challenge datasets. RESULTS: For chicken gut metagenomic datasets, original genome binner MetaBat, Groopm2 and Autometa performed better than other original binner, and MetaWrap combined the binning results of them generated the most high-quality genome bins. For CAMI datasets, Groopm2 achieved the highest purity (> 0.9) with good completeness (> 0.8), and reconstructed the most high-quality genome bins among original genome binners. Compared with Groopm2, MetaBat2 had similar performance with higher completeness and lower purity. Genome refining binners DASTool predicated the most high-quality genome bins among all genomes binners. Most genome binner performed well for unique strains. Nonetheless, reconstructing common strains still is a substantial challenge for all genome binner. CONCLUSIONS: In conclusion, we tested a set of currently available, state-of-the-art metagenomics hybrid binning tools and provided a guide for selecting tools for metagenomic binning by comparing range of purity, completeness, adjusted rand index, and the number of high-quality reconstructed bins. Furthermore, available information for future binning strategy were concluded.


Asunto(s)
Bases de Datos Genéticas , Metagenoma/genética , Metagenómica/métodos , Animales , Pollos/microbiología , Genoma Microbiano , Aprendizaje Automático , Análisis de Secuencia de ADN/métodos , Aprendizaje Automático no Supervisado
8.
Small ; 15(46): e1903952, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31565864

RESUMEN

Solid polymer electrolytes (SPEs)-based all-solid-state lithium-sulfur batteries (ASSLSBs) have attracted extensive research attention due to their high energy density and safe operation, which provide potential solutions to the increasing need for harnessing higher energy densities. There is little progress made, however, in the development of ASSLSBs to improve simultaneously energy density and long-term cycling life, mostly due to the "shuttle effect" of lithium polysulfide intermediates in the SPEs and the low interfacial compatibility between the metal lithium anode and the SPE. In this work, the issues of solid/solid interfacial architecturing through atomic layer deposition of Al2 O3 on poly(ethylene oxide)-lithium bis(trifluoromethanesulfonyl)imide SPE surface are effectively addressed. The Al2 O3 coating promotes the suppression of lithium dendrite formation for over 500 h. ASSLSBs fabricated with two layers of Al2 O3 -coated SPE deliver high gravimetric/areal capacity and Coulombic efficiency, as well as excellent cycling stability and extremely low self-discharge rate. This work provides not only a simple and effective approach to boost the electrochemical performances of SPE-based ASSLSBs, but also enriches the fundamental understanding regarding the underlying mechanism responsible for their performance.

9.
Chemistry ; 25(68): 15472-15476, 2019 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-31523858

RESUMEN

Organic lithium ion batteries (LIBs) are considered as one of the next-generation green electrochemical energy storage (EES) devices. However, obtaining both high capacity and long-term cyclability is still the bottleneck of organic electrode materials for LIBs because of weak structural and chemical stability and low conductivity. Covalent organic frameworks (COFs) show potential to overcome these problems owing to its good stability and high capacity. Herein, the synthesis and characterization of two π-conjugated COFs, derived from the Schiff-base reaction of 2,4,6-triaminopyrimidne (TM) respectively with 1,4-phthalaldehyde (PA) and 1,3,5-triformylbenzene (TB) by a mechanochemical process are presented. As anode materials for LIBs, the COFs exhibit favorable electrochemical performance with the highest reversible discharge capacities of up to 401.3 and 379.1 mAh g-1 at a high current density (1 A g-1 ), respectively, and excellent long-term cyclability with 74.8 and 72.7 % capacity retention after 2000 cycles compared to the initial discharge capacities.

10.
Chemistry ; 25(45): 10710-10717, 2019 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-31115068

RESUMEN

Lithium-sulfur (Li-S) batteries are considered to be one of the most promising energy storage systems owing to their high energy density and low cost. However, their wide application is still limited by the rapid capacity fading. Herein, polydopamine (PDA)-coated N-doped hierarchical porous carbon spheres (NPC@PDA) are reported as sulfur hosts for high-performance Li-S batteries. The NPC core with abundant and interconnected pores provides fast electron/ion transport pathways and strong trapping ability towards lithium polysulfide intermediates. The PDA shell could further suppress the loss of lithium polysulfide intermediates through polar-polar interactions. Benefiting from the dual function design, the NPC/S@PDA composite cathode exhibits an initial capacity of 1331 mAh g-1 and remains at 720 mAh g-1 after 200 cycles at 0.5 C. At the pouch cell level with a high sulfur mass loading, the NPC/S@PDA composite cathode still exhibits a high capacity of 1062 mAh g-1 at a current density of 0.4 mA cm-2 .

11.
Chemistry ; 24(15): 3768-3775, 2018 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-29315950

RESUMEN

As one of the most promising energy storage devices, the practical application of lithium-sulfur batteries is limited by the low electrical conductivity of sulfur and the notable "shuttle effects" of sulfur-based electrodes. In this work, we describe a hierarchically porous N-doped zeolitic imidazolate framework-8 (ZIF-8)-derived carbon nanosphere (N-ZDC) with an outer shell and an inner honeycomb-like interconnected nanosheet network as sulfur host material for high-performance and long-term lithium-sulfur batteries. The N-ZDC serves as multilayered barrier against the dissolution of lithium polysulfides. The porously inner interconnected carbon network of the N-ZDC facilitates the electron and ion transportation, ensures a high sulfur loading, and accommodates a volume expansion of the sulfur species. As a result, the optimized N-ZDC4 /S electrodes displayed high initial specific capacities of 1343, 1182, and 698 mAh g-1 at 0.5, 1, and 2 C, respectively, and an ultraslow capacity decay of only 0.048 % per cycle at 2 C over 800 cycles. Even with a high sulfur loading of 3.1 mg cm-2 , N-ZDC4 /S still delivered a reversible capacity of 956 mAh g-1 and stabilizes at 544 mAh g-1 after 500 cycles at 0.5 C, revealing the great potential of the novel carbon nanospheres for energy storage application.

12.
Clin Immunol ; 165: 4-11, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26911202

RESUMEN

We recently developed a model of lupus serum-induced skin inflammation, which was used to study the pathogenesis of skin injury in systemic lupus erythematosus (SLE). We further characterized the features of lupus serum-induced skin inflammation. This skin inflammation was evident within 3h and lasted for at least two weeks. The skin inflammation was characterized by an influx of monocytic, CD11b+cells and by a scarcity of T and B lymphocytes. Depletion of IgG from the serum abrogated the skin inflammatory response. The skin inflammation was related to lupus patients' skin history but not to SLE disease activity and type of autoantibody. The expression of TNFR1, NF-kB and MCP-1 was increased locally in skin lesions. The TLR9 ligand and lupus serum act synergistically to trigger skin inflammation. These findings suggest that this novel model is valuable for the study of the pathogenesis and therapy of skin injury in SLE.


Asunto(s)
Sueros Inmunes/farmacología , Inflamación/etiología , Lupus Eritematoso Sistémico/sangre , Suero/inmunología , Piel/efectos de los fármacos , Animales , Autoanticuerpos/sangre , Citocinas/sangre , Modelos Animales de Enfermedad , Relación Dosis-Respuesta Inmunológica , Humanos , Inmunoglobulina G/sangre , Inmunoglobulina G/farmacología , Inmunohistoquímica , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Ratones Endogámicos MRL lpr , Piel/patología
13.
Chemistry ; 22(12): 4256-62, 2016 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-26849174

RESUMEN

Porous carbon with high specific surface area (SSA), a reasonable pore size distribution, and modified surface chemistry is highly desirable for application in energy storage devices. Herein, we report the synthesis of nitrogen-containing mesoporous carbon with high SSA (1390 m(2) g(-1)), a suitable pore size distribution (1.5-8.1 nm), and a nitrogen content of 4.7 wt % through a facile one-step self-assembly process. Owing to its unique physical characteristics and nitrogen doping, this material demonstrates great promise for application in both supercapacitors and encapsulating sulfur as a superior cathode material for lithium-sulfur batteries. When deployed as a supercapacitor electrode, it exhibited a high specific capacitance of 238.4 F g(-1) at 1 A g(-1) and an excellent rate capability (180 F g(-1), 10 A g(-1)). Furthermore, when an NMC/S electrode was evaluated as the cathode material for lithium-sulfur batteries, it showed a high initial discharge capacity of 1143.6 mA h g(-1) at 837.5 mA g(-1) and an extraordinary cycling stability with 70.3% capacity retention after 100 cycles.

14.
Chemistry ; 22(46): 16668-16674, 2016 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-27704674

RESUMEN

High-performance electrical double-layer capacitors (EDLCs) require carbon electrode materials with high specific surface area, short ion-diffusion pathways, and outstanding electrical conductivity. Herein, a general approach combing the molten-salt method and chemical activation to prepare N-doped carbon nanosheets with high surface area (654 m2 g-1 ) and adjustable porous structure is presented. Owing to their structural features, the N-doped carbon nanosheets exhibited superior capacitive performance, demonstrated by a maximum capacitance of 243 F g-1 (area-normalized capacitance up to 37 µF cm-2 ) at a current density of 0.5 A g-1 in aqueous electrolyte, high rate capability (179 F g-1 at 20 A g-1 ), and excellent cycle stability. This method provides a new route to prepare porous and heteroatom-doped carbon nanosheets for high-performance EDLCs, which could also be extended to other polymer precursors and even waste biomass.

15.
J Pharmacol Exp Ther ; 352(2): 327-37, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25502803

RESUMEN

Phosphodiesterase 10A (PDE10A) inhibitors have therapeutic potential for the treatment of psychiatric and neurologic disorders, such as schizophrenia and Huntington's disease. One of the key requirements for successful central nervous system drug development is to demonstrate target coverage of therapeutic candidates in brain for lead optimization in the drug discovery phase and for assisting dose selection in clinical development. Therefore, we identified AMG 580 [1-(4-(3-(4-(1H-benzo[d]imidazole-2-carbonyl)phenoxy)pyrazin-2-yl)piperidin-1-yl)-2-fluoropropan-1-one], a novel, selective small-molecule antagonist with subnanomolar affinity for rat, primate, and human PDE10A. We showed that AMG 580 is suitable as a tracer for lead optimization to determine target coverage by novel PDE10A inhibitors using triple-stage quadrupole liquid chromatography-tandem mass spectrometry technology. [(3)H]AMG 580 bound with high affinity in a specific and saturable manner to both striatal homogenates and brain slices from rats, baboons, and human in vitro. Moreover, [(18)F]AMG 580 demonstrated prominent uptake by positron emission tomography in rats, suggesting that radiolabeled AMG 580 may be suitable for further development as a noninvasive radiotracer for target coverage measurements in clinical studies. These results indicate that AMG 580 is a potential imaging biomarker for mapping PDE10A distribution and ensuring target coverage by therapeutic PDE10A inhibitors in clinical studies.


Asunto(s)
Bencimidazoles/farmacología , Encéfalo/enzimología , Inhibidores de Fosfodiesterasa/farmacología , Hidrolasas Diéster Fosfóricas/metabolismo , Tomografía de Emisión de Positrones/métodos , Pirazinas/farmacología , Animales , Bencimidazoles/farmacocinética , Encéfalo/diagnóstico por imagen , Cromatografía Liquida , Femenino , Radioisótopos de Flúor , Humanos , Masculino , Espectrometría de Masas , Estructura Molecular , Papio , Inhibidores de Fosfodiesterasa/química , Inhibidores de Fosfodiesterasa/farmacocinética , Unión Proteica , Pirazinas/farmacocinética , Ensayo de Unión Radioligante , Ratas Sprague-Dawley , Especificidad de la Especie , Estereoisomerismo , Resonancia por Plasmón de Superficie , Distribución Tisular
16.
Chemistry ; 21(6): 2310-4, 2015 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-25469994

RESUMEN

This research presents a simple and efficient method to synthesize porous nitrogen-doped carbon microspheres (PNCM) by the carbonization of microporous poly(terephthalaldehyde-pyrrole) organic frameworks (PtpOF). The common KOH activation process is used to tune the porous texture of the PNCM and produce an activated-PNCM (A-PNCM). The PNCM and A-PNCM with specific surface area of 921 and 1303 m(2) g(-1) , respectively, are demonstrated as promising candidates for EDLCs. At a current density of 0.5 A g(-1) , the specific capacitances of the PNCM and A-PNCM are 248 and 282 F g(-1) , respectively. At the relatively high current density of 20 A g(-1) , the capacitance remaining is 95 and 154 F g(-1) , respectively. Capacity retention of the A-PNCM is more than 92% after 10000 charge/discharge cycles at a current density of 2 A g(-1) .

17.
Nanomicro Lett ; 16(1): 72, 2024 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-38175313

RESUMEN

Lithium-ion thermoelectrochemical cell (LTEC), featuring simultaneous energy conversion and storage, has emerged as promising candidate for low-grade heat harvesting. However, relatively poor thermosensitivity and heat-to-current behavior limit the application of LTECs using LiPF6 electrolyte. Introducing additives into bulk electrolyte is a reasonable strategy to solve such problem by modifying the solvation structure of electrolyte ions. In this work, we develop a dual-salt electrolyte with fluorosurfactant (FS) additive to achieve high thermopower and durability of LTECs during the conversion of low-grade heat into electricity. The addition of FS induces a unique Li+ solvation with the aggregated double anions through a crowded electrolyte environment, resulting in an enhanced mobility kinetics of Li+ as well as boosted thermoelectrochemical performances. By coupling optimized electrolyte with graphite electrode, a high thermopower of 13.8 mV K-1 and a normalized output power density of 3.99 mW m-2 K-2 as well as an outstanding output energy density of 607.96 J m-2 can be obtained. These results demonstrate that the optimization of electrolyte by regulating solvation structure will inject new vitality into the construction of thermoelectrochemical devices with attractive properties.

18.
Nanoscale ; 16(13): 6596-6602, 2024 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-38466180

RESUMEN

Aqueous Zn ion-based fiber-shaped batteries (AZFBs) with the merits of high flexibility and safety have received much attention for powering wearable electronic devices. However, the relatively low specific capacity provided by cathode materials limits their practical application. Herein, we first propose a simple strategy for fabricating high-capacity Zn-iodine fiber-shaped batteries with a high concentration electrolyte and a reduced graphene oxide fiber (GF) cathode. It was found that oxygen functional groups in the graphene sheet demonstrate strong interaction with polyiodides but hinder electron conductivity; thus, the optimal balance between the specific capacity and coulombic efficiency of the GF electrode can be a function of the surface properties at different hydrothermal temperatures. Besides, the regulated high concentration electrolyte effectively suppresses the diffusion of polyiodides, which is attributed to the constrained freedom of water. More importantly, a four-electron redox mechanism was experimentally revealed through in situ Raman spectra. As a result, this fiber-shaped battery delivers a superior high reversible capacity of 390 mA h cm-3 at 1 A cm-3, an excellent rate performance of 125.7 mA h cm-3 at a high current density of 8 A cm-3 and outstanding cycling life with 82% capacitance retention after 2500 cycles.

19.
J Phys Chem Lett ; 15(21): 5738-5746, 2024 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-38775294

RESUMEN

The practical application of lithium-oxygen batteries (LOBs) with ultrahigh theoretical energy density faces the problems of poor kinetics and deficient reversibility. The electrolyte is of vital significance to the electrochemical stability and reaction pathway of LOBs due to the formation of soluble products. Here, a 15-crown-5 ether (15C5) is employed to regulate the solvation structure of Li+ and manipulate the reaction mechanism through regulating the binding ability toward Li+. The promoted dissociation of LiNO3 by 15C5 increases the catalytical active anions in the electrolyte and stabilizes the Li-containing reduced oxygen species to promote the solution pathway of discharge product growth. Besides, 15C5 also facilitates the kinetics of the electrochemical decomposition of Li2O2 and prolongs the cycle life to 178 cycles. This work inspires a novel approach to improve the battery performance through electrolyte component design.

20.
ACS Appl Mater Interfaces ; 16(20): 26209-26216, 2024 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-38733341

RESUMEN

Thick electrodes with high mass loading and increased content of active materials are critical for achieving higher energy density in contemporary lithium-ion batteries (LIBs). Nonetheless, producing thick electrodes through the commonly used slurry coating technology remains a formidable challenge. In this study, we have addressed this challenge by developing a dry electrode technology by using ultralong multiwalled carbon nanotubes (MWCNT) as a conductive additive and secondary binder. The mixing process of electrode compositions and the fibrillation process of the polytetrafluoroethylene (PTFE) binder were optimized. The resulting LiCoO2 (LCO) electrode exhibited a remarkable mass loading of 48 mg cm-2 and an active material content of 95 wt %. Notably, the thick LCO electrode demonstrated a superior mechanical strength and electrochemical performance. After 100 cycles at a current density of 1/3 C, the electrode still exhibited a capacity retention of 91% of its initial capacity. This dry electrode technology provides a practicable and scalable approach to the powder-to-film LIB electrode manufacturing process.

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