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2.
Front Genet ; 15: 1381690, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38650857

RESUMO

The ALOG (Arabidopsis LSH1 and Oryza G1) family proteins, namely, DUF640 domain-containing proteins, have been reported to function as transcription factors in various plants. However, the understanding of the response and function of ALOG family genes during reproductive development and under abiotic stress is still largely limited. In this study, we comprehensively analyzed the structural characteristics of ALOG family proteins and their expression profiles during inflorescence development and under abiotic stress in rice. The results showed that OsG1/OsG1L1/2/3/4/5/6/7/8/9 all had four conserved helical structures and an inserted Zinc-Ribbon (ZnR), the other four proteins OsG1L10/11/12/13 lacked complete Helix-1 and Helix-2. In the ALOG gene promoters, there were abundant cis-acting elements, including ABA, MeJA, and drought-responsive elements. Most ALOG genes show a decrease in expression levels within 24 h under ABA and drought treatments, while OsG1L2 expression levels show an upregulated trend under ABA and drought treatments. The expression analysis at different stages of inflorescence development indicated that OsG1L1/2/3/8/11 were mainly expressed in the P1 stage; in the P4 stage, OsG1/OsG1L4/5/9/12 had a higher expression level. These results lay a good foundation for further studying the expression of rice ALOG family genes under abiotic stresses, and provide important experimental support for their functional research.

3.
ACS Appl Mater Interfaces ; 15(10): 12908-12914, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36867502

RESUMO

As an emerging energy storage concept, Al-CO2 batteries have not yet been demonstrated as a rechargeable system that can deliver a high discharge voltage and a high capacity. In this work, we present a homogeneous redox mediator to access a rechargeable Al-CO2 battery with an ultralow overpotential of 0.05 V. In addition, the resulting rechargeable Al-CO2 cell can maintain a high discharge voltage of 1.12 V and delivers a high capacity of 9394 mAh/gcarbon. Nuclear magnetic resonance (NMR) analysis indicates that the discharge product is aluminum oxalate which can facilitate the reversible operation of Al-CO2 batteries. The rechargeable Al-CO2 battery system demonstrated here holds great promise as a low-cost and high-energy alternative for future grid energy storage applications. Meanwhile, the Al-CO2 battery system could facilitate capture and concentration of atmospheric CO2, ultimately benefiting both the energy and environmental sectors of society.

4.
Materials (Basel) ; 16(4)2023 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-36837199

RESUMO

Ca(OH)2 nanoparticles are effective materials for cultural heritage restoration, hazardous substance absorption and photocatalyst. However, many methods are complex, and the particle sizes are usually above 80-100 nm, involving mediocre efficacy for application in the stone restoration field. In this work, Nano Ca(OH)2 with diameters less than 70 nm and composited with Graphene Quantum Dots (GQDs) were successfully synthesized in aqueous media. The morphology and structure of the nanoparticles were investigated with TEM, HRTEM, XRD, Raman and FTIR. The particle size distribution and relative kinetic stability of the Ca(OH)2 in ethanol were performed using a laser particle size analyzer and spectrophotometer. Firstprinciple calculations based on the spin-polarized density functional theory (DFT) were carried out to study the reaction process and combination model. The nanoparticles, as prepared, are composed of primary hexagonal crystals and high ammoniated precursors, which have a positive effect on reducing the grain size, and interacted with the GQDs hybrid process. According to the First-principle calculations results, the energy variation of the whole reaction process and the bonding mode between Ca(OH)2 and GQDs can be understood better.

5.
Phytochemistry ; 207: 113581, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36592859

RESUMO

Four undescribed and two known cucurbitane-type triterpenoids, including two heterodimers, elaeocarpudubins A and B, were isolated from the branches of Elaeocarpus dubius (Elaeocarpaceae). The chemical structures of these undescribed isolates were determined by analyses of 1D and 2D NMR and MS data, electronic circular dichroism (ECD) calculations, and chemical transformation. Biogenetically, elaeocarpudubins A and B might be derived from cucurbitacin F through Michael addition with vitamin C and (-)-catechin, respectively. These six isolates were evaluated for their cytotoxic activities against human leukemia HL-60, human lung adenocarcinoma A549, human hepatoma SMMC-7721, human breast cancer MCF-7, human colon cancer SW480, and paclitaxel-resistant A549 (A549/Taxol) cell lines, for their antioxidant properties using the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging assay, and for their differentiation effects on nerve growth factor (NGF)-mediated neurite outgrowth in rat pheochromocytoma PC12 cells. Cucurbitacins F (IC50 of 4.98-38.11 µM) and D (IC50 of 0.03-4.40 µM) showed growth-inhibitory activities against these six cancer cell lines. Elaeocarpudubin B (IC50 of 61.04 µM) and elaeocarpudoside B (IC50 of 6.93 µM) showed antioxidant activities. Elaeocarpudubin B and elaeocarpudoside B also showed neurite outgrowth-promoting activities in PC12 cells at a concentration of 10 µM.


Assuntos
Elaeocarpaceae , Triterpenos , Ratos , Animais , Humanos , Antioxidantes/farmacologia , Estrutura Molecular , Triterpenos/química , Células PC12 , Esqueleto , Elaeocarpaceae/química
6.
Nano Lett ; 23(3): 1085-1092, 2023 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-36649599

RESUMO

Curved ultrathin PtPd nanodendrites (CNDs) with long-range compressive strain and highly branched feature are first prepared by a functional surfactant-induced strategy. Precise synthesis realized the construction of both curved and flat PtPd nanodendrites (NDs) with the same atomic ratio, which contributed to exploration of the strain effect on electrocatalytic performance alone. Abundant evidence is provided to confirm that the long-range compressive strain in curved PtPd architectures can effectively tailor the local coordination environment of active sites, lower the position of the d-band center, weaken the adsorption energy of the intermediates (e.g., H* and CO*), and ultimately increase their intrinsic activity. The density functional theory (DFT) calculations further reveal that the introduction of compressive strain weakens the Gibbs free-energy of the intermediate (ΔGH*), which is favorable for accelerating the hydrogen evolution reaction (HER) kinetics. A similar enhanced electrocatalytic performance can also be found in the methanol oxidation reaction (MOR).

7.
Heliyon ; 8(9): e10442, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36091957

RESUMO

In Beijing area, the precious stone objects often suffer from the black crusts on the specific parts of the objects, in order to understand the forming mechanism of the black crusts, samples from the stone sculptures in Beijing Stone Carving Art Museum, ZHIHUA Temple and Museum of Western Zhou Yandu Relics were taken and studied. Nondestructive measurement was carried out firstly to acquire main elements of the samples by portable X-ray spectrum (pXRF). Morphology and microstructure of typical black crust samples were examined by ultra-depth of field microscope (UDFM) and scanning electron microscopy coupled with energy dispersive spectroscopy (SEM-EDS). Compositions of black crusts and body rocks were evaluated with X-ray diffraction (XRD), Raman spectra and mapping. Inductively coupled plasma optical emission spectrometry (ICP-OES) and pyrolysis-gas chromatography/mass spectrometry (Py-GCMS) were used to identify the major pollution sources leading to the black crusts. Through this study, the composition of the black crusts was revealed. Different gypsum crystals and carbonaceous species were found. Pollutant elements analysis and pyrolysis products provide indicators of the pollution sources. As consequence of strong photochemical oxidation processes and the high temperature from June to September in Beijing, more acid rain precursors can be formed. Frequent sulphation process occurs on the CaCO3/CaMg(CO3)2 surface. Combining morphology results and atmospheric data, the formation of black crusts in Beijing can be deduced.

8.
Sci Rep ; 11(1): 16557, 2021 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-34400663

RESUMO

Recently, a bowl containing charred suspected tea remains unearthed from the early stage of Warring States period tomb in Zoucheng City, Shandong Province, China. To identify the remains is significant for understanding the origin of tea and tea drinking culture. Scientific investigations of the remains were carried out by using calcium phytoliths analysis, Fourier transform infrared spectroscopy (FTIR), Gas Chromatograph Mass Spectrometer (GC/MS) and Thermally assisted hydrolysis-methylation Pyrolysis Gas Chromatography Mass Spectrometry (THM-Py-GC/MS) techniques. Modern tea and modern tea residue were used as reference samples. Through phytoliths analyses, calcium phytoliths identifiable from tea were determined in the archeological remains. The infrared spectra of the archaeological remains was found similar as modern tea residue reference sample. In addition, the biomarker compound of tea-caffeine was determined in the archaeological remains by THM-Py-GC/MS analysis. Furthermore, through GC/MS analysis, some compounds were found both in the archeological remains and the modern tea residue reference samples. Putting the information together, it can be concluded that the archaeological remains in the bowl are tea residue after boiling or brewing by the ancient.

9.
Nat Prod Bioprospect ; 11(5): 545-555, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34061296

RESUMO

One novel spirolactone, aquilarisinolide (1), three new sesquiterpenoids, (2R,4S,5R,7R)-2-hydroxyeremophila-9,11-dien-8-one (2), (1R,4S,5S,7R,11R)-13-hydroxyepidaphnauran-9-en-8-one (3), and (4R,5S,7R,8S,10S,13R)-8,13-dihydroxyrotunda-1,11-dien-3-one (4), together with 13 known compounds (5-17) were isolated from the resinous heartwood of Aquilaria sinensis (Thymelaeaceae). The structures of the new compounds were elucidated based on the analysis of NMR and MS data and theoretical calculations their ECD spectra. The isolated compounds were evaluated for their protective activities against PC12 cell injury induced by corticosterone (CORT) and 1-methyl-4-phenylpyridine ion (MPP+), as well as inhibitory activities against BACE1. Compound 4, 5,6-dihydroxy-2-(2-phenylethyl)chromone (5), daphnauranol B (7), 6-methoxy-2-[2-(3-methyoxyphenyl)ethyl]chromone (10), isoagarotetrol (14), and 1-hydroxy-1,5-diphenylpentan-3-one (16) showed significant protective effects on CORT-induced injury in PC12 cells at a concentration of 20 µM (P < 0.001). Isoagarotetrol (14) showed a significant protective effect on MPP+-induced injury in PC12 cells at a concentration of 20 µM (P < 0.001), while compound 4 showed a moderate activity (P < 0.01). The BACE1-inhibitory activities of all tested compounds were very weak with less than 30% inhibition at a concentration of 20 µM.

10.
BMC Vet Res ; 16(1): 444, 2020 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-33203451

RESUMO

BACKGROUND: Triazine coccidiostats are widely used in chickens and turkeys for coccidiosis control. Ethanamizuril is a novel triazine compound that exhibits anticoccidial activity in poultry. This study was designed to evaluate the subchronic toxicity of ethanamizuril in beagle dogs at doses of 12, 60 or 300 mg/kg/day in diet for 90 days. RESULTS: Ethanamizuril was well tolerated at low and middle dosages in beagle dogs, and no drug-related toxical effects were observaed in terms of survival, clinical observations, organs weight and damage in these dose groups. However, in high dose administration group, food consumption and histologic changes in kidneys were noticed in both sexes of beagle dog, although the renal lesions were finally resolved at the end of 4 weeks exposure of ethanamizuril. CONCLUSIONS: No-observed-adverse-effect level (NOAEL) was considered for ethanamizuril at dose of 60 mg/kg/day in Beagle dog. This result added toxicity effects of ethanamizuril to the safety database, which might guide safely using of ethanamizuril as a novel coccidiostat.


Assuntos
Coccidiostáticos/toxicidade , Triazinas/toxicidade , Administração Oral , Animais , Coccidiostáticos/administração & dosagem , Cães , Relação Dose-Resposta a Droga , Comportamento Alimentar/efeitos dos fármacos , Feminino , Rim/efeitos dos fármacos , Masculino , Triazinas/administração & dosagem
11.
Small ; 15(44): e1903166, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31513358

RESUMO

Transition metal phosphides are a new class of materials generating interest as alternative negative electrodes in lithium-ion batteries. However, metal phosphide syntheses remain underdeveloped in terms of simultaneous control over phase composition and 3D nanostructure. Herein, M13 bacteriophage is employed as a biological scaffold to develop 3D nickel phosphide nanofoams with control over a range of phase compositions and structural elements. Virus-templated Ni5 P4 nanofoams are then integrated as thin-film negative electrodes in lithium-ion microbatteries, demonstrating a discharge capacity of 677 mAh g-1 (677 mAh cm-3 ) and an 80% capacity retention over more than 100 cycles. This strong electrochemical performance is attributed to the virus-templated, nanostructured morphology, which remains electronically conductive throughout cycling, thereby sidestepping the need for conductive additives. When accounting for the mass of additional binder materials, virus-templated Ni5 P4 nanofoams demonstrate the highest practical capacity reported thus far for Ni5 P4 electrodes. Looking forward, this synthesis method is generalizable and can enable precise control over the 3D nanostructure and phase composition in other metal phosphides, such as cobalt and copper.

12.
Biomed Chromatogr ; 33(11): e4652, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31322281

RESUMO

Ethanamizuril is a new triazine compound that has the potential to be a novel anticoccidial drug. Toxicological studies in experimental rats were performed to understand the safety profile of ethanamizuril for drug product development. In this study, a novel, selective and accurate ultra-performance liquid chromatography tandem mass spectrometry method has been developed for the determination of ethanamizuril concentrations in rat plasma. With 4-nitro-o-cresol as an internal standard, sample pretreatment involved a one-step extraction with acetonitrile of 100 µL plasma. The detection was carried out by electrospray ionization mass spectrometry in negative ion mode with selected ion recording. The standard curves were linear (r2 ≥ 0.999) over the concentration range of 0.1-100 µg/mL. The relative standard deviations of intra- and inter-day precisions were less than 8.4 and 8.87%, respectively. The mean extraction recovery of ethanamizuril from rat plasma was 97.68-102.57%. The method was fully validated and successfully applied to monitor plasma concentrations of ethanamizuril in a short-term toxicity study and two-generation reproduction toxicity study. The result of the study confirmed that the elimination of ethanamizuril in rats is slow.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Coccidiostáticos/sangue , Espectrometria de Massas em Tandem/métodos , Triazinas/sangue , Animais , Coccidiostáticos/química , Coccidiostáticos/farmacocinética , Feminino , Limite de Detecção , Modelos Lineares , Masculino , Ratos , Ratos Sprague-Dawley , Reprodutibilidade dos Testes , Espectrometria de Massas por Ionização por Electrospray , Triazinas/química , Triazinas/farmacocinética
13.
Sci Adv ; 4(3): eaao6243, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29582017

RESUMO

Electrodeposition is a widely practiced method for creating metal, colloidal, and polymer coatings on conductive substrates. In the Newtonian liquid electrolytes typically used, the process is fundamentally unstable. The underlying instabilities have been linked to failure of microcircuits, dendrite formation on battery electrodes, and overlimiting conductance in ion-selective membranes. We report that viscoelastic electrolytes composed of semidilute solutions of very high-molecular weight neutral polymers suppress these instabilities by multiple mechanisms. The voltage window ΔV in which a liquid electrolyte can operate free of electroconvective instabilities is shown to be markedly extended in viscoelastic electrolytes and is a power-law function, ΔV : η1/4, of electrolyte viscosity, η. This power-law relation is replicated in the resistance to ion transport at liquid/solid interfaces. We discuss consequences of our observations and show that viscoelastic electrolytes enable stable electrodeposition of many metals, with the most profound effects observed for reactive metals, such as sodium and lithium. This finding is of contemporary interest for high-energy electrochemical energy storage.

14.
Angew Chem Int Ed Engl ; 57(4): 992-996, 2018 01 22.
Artigo em Inglês | MEDLINE | ID: mdl-29227557

RESUMO

We report a facile in situ synthesis that utilizes readily accessible SiCl4 cross-linking chemistry to create durable hybrid solid-electrolyte interphases (SEIs) on metal anodes. Such hybrid SEIs composed of Si-interlinked OOCOR molecules that host LiCl salt exhibit fast charge-transfer kinetics and as much as five-times higher exchange current densities, in comparison to their spontaneously formed analogues. Electrochemical analysis and direct optical visualization of Li and Na deposition in symmetric Li/Li and Na/Na cells show that the hybrid SEI provides excellent morphological control at high current densities (3-5 mA cm-2 ) for Li and even for notoriously unstable Na metal anodes. The fast interfacial transport attributes of the SEI are also found to be beneficial for Li-S cells and stable electrochemical cycling was achieved in galvanostatic studies at rates as high as 2 C. Our work therefore provides a promising approach towards rational design of multifunctional, elastic SEIs that overcome the most serious limitations of spontaneously formed interphases on high-capacity metal anodes.

15.
Acc Chem Res ; 51(1): 80-88, 2018 01 16.
Artigo em Inglês | MEDLINE | ID: mdl-29227617

RESUMO

Stable electrochemical interphases play a critical role in regulating transport of mass and charge in all electrochemical energy storage (EES) systems. In state-of-the-art rechargeable lithium ion batteries, they are rarely formed by design but instead spontaneously emerge from electrochemical degradation of electrolyte and electrode components. High-energy secondary batteries that utilize reactive metal anodes (e.g., Li, Na, Si, Sn, Al) to store large amounts of charge by alloying and/or electrodeposition reactions introduce fundamental challenges that require rational design in order to stabilize the interphases. Chemical instability of the electrodes in contact with electrolytes, morphological instability of the metal-electrolyte interface upon plating and stripping, and hydrodynamic-instability-induced electroconvection of the electrolyte at high currents are all known to cause metal electrode-electrolyte interfaces to continuously evolve in morphology, uniformity, and composition. Additionally, metal anodes undergo large changes in volume during lithiation and delithiation, which means that even in the rare cases where spontaneously formed solid electrode-electrolyte interphases (SEIs) are in thermodynamic equilibrium with the electrode, the SEI is under dynamic strain, which inevitably leads to cracking and/or rupture during extended battery cycling. There is an urgent need for interphases that are able to overcome each of these sources of instability with minimal losses of electrolyte and electrode components. Complementary chemical synthesis strategies are likewise urgently needed to create self-limited and mechanically durable SEIs that are able to flex and shrink to accommodate volume change. These needs are acute for practically relevant cells that cannot utilize large excesses of anode and electrolyte as employed in proof-of-concept-type experiments reported in the scientific literature. This disconnect between practical needs and research practices makes it difficult to translate promising literature results, underscoring the importance of research designed to reveal principles for good interphase design. This Account considers the fundamental processes involved in interphase formation, stability, and failure and on that basis identifies design principles, synthesis procedures, and characterization methods for enabling stable metal anode-electrolyte interfaces for EES. We first review results from experimental, continuum theoretical, and computational analyses of interfacial transport to identify fundamental connections between the composition of the SEI at metal-electrolyte interfaces and stability. Design principles and tools for creating stable artificial solid-electrolyte interphases (ASEIs) based on polymers, ionic liquids, ceramics, nanoparticles, salts, and their combinations are subsequently discussed. Interphases composed of a second electrochemically active material that stores charge by different processes from the underlying metal electrode emerge as particularly attractive routes toward so-called hybrid electrodes that enable facile scale-up of ASEI designs for commercially relevant EES.

16.
Nat Commun ; 8(1): 898, 2017 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-29026067

RESUMO

Secondary batteries based on earth-abundant sodium metal anodes are desirable for both stationary and portable electrical energy storage. Room-temperature sodium metal batteries are impractical today because morphological instability during recharge drives rough, dendritic electrodeposition. Chemical instability of liquid electrolytes also leads to premature cell failure as a result of parasitic reactions with the anode. Here we use joint density-functional theoretical analysis to show that the surface diffusion barrier for sodium ion transport is a sensitive function of the chemistry of solid-electrolyte interphase. In particular, we find that a sodium bromide interphase presents an exceptionally low energy barrier to ion transport, comparable to that of metallic magnesium. We evaluate this prediction by means of electrochemical measurements and direct visualization studies. These experiments reveal an approximately three-fold reduction in activation energy for ion transport at a sodium bromide interphase. Direct visualization of sodium electrodeposition confirms large improvements in stability of sodium deposition at sodium bromide-rich interphases.The chemistry at the interface between electrolyte and electrode plays a critical role in determining battery performance. Here, the authors show that a NaBr enriched solid-electrolyte interphase can lower the surface diffusion barrier for sodium ions, enabling stable electrodeposition.

17.
Adv Mater ; 29(12)2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28112842

RESUMO

A sodium metal anode protected by an ion-rich polymeric membrane exhibits enhanced stability and high-Columbic efficiency cycling. Formed in situ via electropolymerization of functional imidazolium-type ionic liquid monomers, the polymer membrane protects the metal against parasitic reactions with electrolyte and, for fundamental reasons, inhibits dendrite formation and growth. The effectiveness of the membrane is demonstrated using direct visualization of sodium electrodeposition.

18.
Nat Commun ; 7: 11722, 2016 06 09.
Artigo em Inglês | MEDLINE | ID: mdl-27277345

RESUMO

High-energy rechargeable batteries based on earth-abundant materials are important for mobile and stationary storage technologies. Rechargeable sodium-sulfur batteries able to operate stably at room temperature are among the most sought-after platforms because such cells take advantage of a two-electron-redox process to achieve high storage capacity from inexpensive electrode materials. Here we report a room-temperature sodium-sulfur battery that uses a microporous carbon-sulfur composite cathode, and a liquid carbonate electrolyte containing the ionic liquid 1-methyl-3-propylimidazolium-chlorate tethered to SiO2 nanoparticles. We show that these cells can cycle stably at a rate of 0.5 C (1 C=1675, mAh g(-1)) with 600 mAh g(-1) reversible capacity and nearly 100% Coulombic efficiency. By means of spectroscopic and electrochemical analysis, we find that the particles form a sodium-ion conductive film on the anode, which stabilizes deposition of sodium. We also find that sulfur remains interred in the carbon pores and undergo solid-state electrochemical reactions with sodium ions.

19.
ChemSusChem ; 9(13): 1600-6, 2016 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-27225026

RESUMO

Electrochemical cells that utilize metals in the anode and an ambient gas as the active material in the cathode blur the lines between fuel cells and batteries. Such cells are under active consideration worldwide because they are considered among the most promising energy storage platforms for electrified transportation. Li-air batteries are among the most actively investigated cells in this class, but long-term challenges, such as CO2 contamination of the cathode gas and electrolyte decomposition, are associated with loss of rechargeability owing to metal carbonate formation in the cathode. Remediation of the first of these problems adds significant infrastructure burdens to the Li-air cell that bring into question its commercial viability. Several recent studies offer contradictory evidence, namely, that the presence of substantial fractions of CO2 in the cathode gas stream can have significant benefits, including increasing the already high specific energy of a Li-O2 cell by as much as 200 %. In this report, we consider electrochemical processes in model Na-O2 /CO2 cells and find that, provided the electrode/electrolyte interfaces are electrochemically stable, such cells are able to deliver both exceptional energy storage capacity and stable long-term charge-discharge cycling behaviors at room temperature.


Assuntos
Dióxido de Carbono/química , Fontes de Energia Elétrica , Oxigênio/química , Sódio/química , Eletroquímica
20.
ACS Nano ; 10(1): 1050-9, 2016 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-26634409

RESUMO

The rechargeable lithium-sulfur (Li-S) battery is an attractive platform for high-energy, low-cost electrochemical energy storage. Practical Li-S cells are limited by several fundamental issues, including the low conductivity of sulfur and its reduction compounds with Li and the dissolution of long-chain lithium polysulfides (LiPS) into the electrolyte. We report on an approach that allows high-performance sulfur-carbon cathodes to be designed based on tethering polyethylenimine (PEI) polymers bearing large numbers of amine groups in every molecular unit to hydroxyl- and carboxyl-functionalized multiwall carbon nanotubes. Significantly, for the first time we show by means of direct dissolution kinetics measurements that the incorporation of CNT-PEI hybrids in a sulfur cathode stabilizes the cathode by both kinetic and thermodynamic processes. Composite sulfur cathodes based the CNT-PEI hybrids display high capacity at both low and high current rates, with capacity retention rates exceeding 90%. The attractive electrochemical performance of the materials is shown by means of DFT calculations and physical analysis to originate from three principal sources: (i) specific and strong interaction between sulfur species and amine groups in PEI; (ii) an interconnected conductive CNT substrate; and (iii) the combination of physical and thermal sequestration of LiPS provided by the CNT=PEI composite.

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