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1.
Dalton Trans ; 52(31): 10789-10794, 2023 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-37477527

RESUMO

The slow redox kinetics and shuttling behavior of the intermediate lithium polysulfides constrain the further development of lithium-sulfur (Li-S) electrochemistry. A yolk-shell In2S3@void@carbon hybrid engineered to host the sulfur for Li-S batteries is prepared by using a multi-layered assembly method. The In2S3/electrolyte interface acted as powerful adsorption and activation sites for soluble polysulfides, which is demonstrated using density functional theory (DFT) calculations. Moreover, the carbon shell provides redundancy for volume-changes during the cycles. The results indicate that yolk-shell In2S3@S@C hybrid cathode shows good reversibility and rate capability, which preserves 563.6 mA h g-1 after 500 cycles at 0.5 C, indicating the potential for developing high-performance battery systems.

2.
Nanotechnology ; 34(32)2023 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-37146591

RESUMO

Since current graphite-based lithium-ion battery anode has a low theoretical capacity, the development of high-performance lithium-ion battery is severely restricted. Here, novel hierarchical composites composing of microdisc and the secondarily grown nanosheets and nanowires are developed, taking NiMoO4nanosheets and Mn3O4nanowires growing on Fe2O3microdiscs as demonstrating examples. The growth processes of the hierarchical structures have been investigated by adjusting a series of preparation conditions. The morphologies and structures have been characterized by using scanning electron microscopy, transmission electron microscope and x-ray diffraction. Fe2O3@Mn3O4composite-based anode displays a capacity of 713 mAh g-1after 100 cycles at 0.5 A g-1with a high Coulombic efficiency. A good rate-performance is also achieved. Fe2O3@NiMoO4anode delivers 539 mAh g-1after 100 cycles at 0.5 A g-1, which is obviously higher than that of pure Fe2O3. The hierarchical structure is conducive to improve the transport of electrons and ions, and provide numerous active sites, thus significantly enhancing the electrochemical performance. Moreover, the electron transfer performance is investigated by using density functional theory calculations. It is expected the findings presented here and the rational engineering of nanosheets/nanowires on microdiscs would be applicable for developing many other high-performance energy-storage composites.

3.
ACS Nano ; 16(9): 15369-15381, 2022 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-36049053

RESUMO

Magnesium/lithium hybrid-ion batteries (MLHBs) combine the advantages of high safety and fast ionic kinetics, which enable them to be promising emerging energy-storage systems. Here, a high-performance MLHB using a modified all-phenyl complex with a lithium bis(trifluoromethanesulfonyl)imide electrolyte and a NiCo2S4 cathode on a copper current collector is developed. A reversible conversion involving a copper collector with NiCo2S4 efficiently avoids the electrolyte dissociation and diffusion difficulties of Mg2+ ions, enabling low polarization and fast redox, which is verified by X-ray absorption near edge structure analysis. Such combination affords the best MLHB among all those ever reported, with a reversible capacity of 204.7 mAh g-1 after 2600 cycles at 2.0 A g-1, and delivers an ultrahigh full electrode-basis energy density of 708 Wh kg-1. The developed MLHB also achieves good rate performance and temperature tolerance at -10 and 50 °C with a low electrolyte consumption. The hybrid-ion battery system presented here could inspire a broad set of engineering potentials for high-safety battery technologies and beyond.

4.
Adv Sci (Weinh) ; 9(3): e2103517, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34845856

RESUMO

The shuttling behavior and slow conversion kinetics of the intermediate lithium polysulfides are the severe obstacles for the application of lithium-sulfur (Li-S) batteries over a wide temperature range. Here, an engineered lamellar yolk-shell structure of In2 O3 @void@carbon for the Li-S battery cathode is developed for the first time to construct a powerful barrier that effectively inhibits the shuttling of polysulfides. On the basis of the unique nanochannel-containing morphology, the continuous kinetic transformation of sulfur and polysulfides is confined in a stable framework, which is demonstrated by using X-ray nanotomography. The constructed Li-S battery exhibits a high cycling capability over 1000 cycles at 1.0 C with a capacity decay rate as low as 0.038% per cycle, good rate performance, and temperature tolerance at -10, 25, and 50 °C. A nondestructive in situ monitoring method of the interfacial reaction resistance in different cycling stages is proposed, which provides a new analysis perspective for the development of emerging electrochemical energy-storage systems.

5.
Chem Commun (Camb) ; 56(17): 2618-2621, 2020 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-32016255

RESUMO

A novel hierarchical composite consisting of an ordered NiCo2O4 nanowire array growing on the lateral side of a Fe2O3 microdisc is presented, which was confirmed by X-ray holography technology on a synchrotron radiation station. The composite-based Li-ion battery anode exhibits a high capacity of 1528 mA h g-1 after 200 cycles at 0.2C, a recoverable rate-performance after repeated tests, and robust mechanical properties.

6.
Nanotechnology ; 31(3): 035401, 2020 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-31557745

RESUMO

High capacity and stable anodes are demanded since the current graphite-based anode does not meet the high-performance requirements of emerging Li-ion battery systems. Herein, we present a novel spring-shaped hierarchical SiO2@Co3O4 nanowire composite, which exhibits good Li-storage performance. The special structure is able to effectively accommodate the change in structure during charge-discharge, and the coaxial hierarchical morphology enables rapid Li+ ion and electron transfer. The spring-shaped SiO2@Co3O4 anode exhibits a capacity of 770 mAh g-1, along with a high Coulombic efficiency of 99.8% after 400 cycles. A stable rate performance even after three rounds of measurements is also achievable. In addition, the real-time lithiation of the SiO2@Co3O4 composite is investigated through an in situ transmission electron microscopy technology, which demonstrates the stable structure of the spring-shaped SiO2@Co3O4 composite during the rapid lithiation process.

7.
Wei Sheng Yan Jiu ; 44(4): 623-7, 631, 2015 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-26454961

RESUMO

OBJECTIVE: To explore the effects of tyrosine oxidized products (TOP) on the redox state of rats myocardium and investigate the oxidative damage mechanism. METHODS: Male SD Rats were randomly assigned to three groups and treated respectively with normal diet (Group C), 440 mg/kg TOP (Group TOP), 440 mg/kg tyrosine oxidized products plus 5 mg/kg lipoic acid (Group TOP + LA). Indicators of oxidative stress in blood and myocardial were measured at the end of 6 weeks, 12 weeks and 24 weeks. RT-PCR was used to detect mRNA expression of Nrf2, Trx, NF-κB and AP-1 in myocardium. RESULTS: Compared to the control group (Group C), reactive oxygen species (ROS), carbonyl (PC), malondialdehyde (MDA), dityrosine (Dityr), 3-nitrotyrosine (3-NT) in rats blood and myocardium were all significantly increased in the TOP group (P < 0.05). Total antioxidant capacity (T-AOC), catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), reducing glutathione (GSH) and oxidized glutathione (GSSG) levels all decreased significantly (P < 0.05). The mRNA expression of Nrf2, Trx-1, NF-κB, AP-1 RNA significantly up-regulated (P < 0.05) in the TOP group compared to the control. CONCLUSION: Tyrosine oxidized products impairs antioxidant defense system and lead to accumulation of protein oxidation products in rats myocardium. Moreover, lipoic acid performs a positive effect in the protective reaction, which may adjusted by regulation of redox signaling pathway.


Assuntos
Coração/efeitos dos fármacos , Oxirredução/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Tirosina/farmacologia , Animais , Antioxidantes/farmacologia , Catalase , Glutationa , Glutationa Peroxidase , Masculino , Malondialdeído , NF-kappa B , Ratos , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio , Superóxido Dismutase , Ácido Tióctico , Fator de Transcrição AP-1 , Tirosina/análogos & derivados
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