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1.
Journal of Solid State Electrochemistry - The morphology of Co-based zeolitic imidazolate framework is affected by the molar ratio of 2-methylimidazole and Co2+ used during the synthesis. In this...  相似文献   

2.
Mn-based oxide-loaded porous carbon nanofiber anodes, exhibiting large reversible capacity, excellent capacity retention, and good rate capability, are fabricated by carbonizing electrospun polymer/Mn(CH3COO)2 composite nanofibers without adding any polymer binder or electronic conductor. The excellent electrochemical performance of these organic/inorganic nanocomposites is a result of the unique combinative effects of nano-sized Mn-based oxides and carbon matrices as well as the highly-developed porous composite nanofiber structure, which make them promising anode candidates for high-performance rechargeable lithium-ion batteries.  相似文献   

3.
Nano-sized caiboxylales Na2C7H3NO4 and Na2C6H2N2O4 were prepared and investigated as anode materials for lithium-ion batteries.Both carboxylates exhibit high reversible capacities around 190 mAh/g above a cut-off voltage of 0.8 V vs.Li+/Li.potentially improving the safety of the batteries.In addition,good rate performance and long cycle life of these carboxylates make them promising candidates as anode materials for lithium-ion batteries.  相似文献   

4.
Using a soft-template assisted method, well-organized Cu/TiO(2) nanoarchitectured electrode materials with copper nanowires as their own current collectors are synthesized by controlled hydrolysis of tetrabutyl titanate in the presence of Cu-based nanowires, and investigated by SEM, TEM, XRD, Raman spectroscopy and electrochemical tests towards lithium storage. Two types of Cu/TiO(2) nanocomposites with different TiO(2) grain sizes are obtained by using different thermal treatments. The two types of Cu/TiO(2) nanocomposites show much enhanced rate performances compared with bare TiO(2). A high-rate capability (reversible capacity at 7500 mA g(-1) still accounts for 58% of its initial capacity at 50 mA g(-1)) is observed for the Cu/TiO(2) nanocomposite with smaller TiO(2) grain size. The improvements can be attributed to the integrated Cu nanowires as mechanical supports and efficient current collectors. A cell made from the Cu/TiO(2) nanoarchitectured electrodes exhibits promise as an energy storage device with both high energy and high power densities.  相似文献   

5.
Tin oxide (SnO2)/graphene composite was synthesized from SnCl2?·?2H2O and graphene oxide (GO) by a wet chemical-hydrothermal route. The GO was reduced to graphene nanosheet (GNS) and flower-like SnO2 nano-crystals with size about 40 nm were homogeneously distributed on the surface of GNS. The SnO2/graphene composites delivered a superior first discharge capacity of 1941.9 mAhg?1 with a reversible capacity of 901.7 mAhg?1 at the current density of 100 mAg?1. Moreover, even at higher densities of 200 and 500 mAg?1, the SnO2/graphene composite still maintained enhanced cycling stability. After 40 cycles, the discharge capacity was still maintained at 691.1 mAhg?1 at the current density of 100 mAg?1. The SnO2/graphene composite displayed an outstanding Li-battery performance with large reversible capacity and enhanced rate performance, which can be attributed to the highly uniform distribution of SnO2 nanoparticles and high reduction degree of graphene. This result strongly indicates that the SnO2/graphene composite was a promising anode material in high-performance lithium-ion batteries.  相似文献   

6.
Journal of Solid State Electrochemistry - TiO2@SnO2@TiO2 triple-shell nanotubes are fabricated using electrospun polyacrylonitrile (PAN) nanofiber template and plasma-enhanced atomic layer...  相似文献   

7.
Carbon coated magnetite (Fe3O4) core-shell nanorods were synthesized by a hydrothermal method using Fe2O3 nanorods as the precursor. Transmission electron spectroscopy (TEM) and high resolution TEM (HRTEM) analysis indicated that a carbon layer was coated on the surfaces of the individual Fe3O4 nanorods. The electrochemical properties of Fe3O4/carbon nanorods as anodes in lithium-ion cells were evaluated by cyclic voltammetry, ac impedance spectroscopy, and galvanostatic charge/discharge techniques. The as-prepared Fe3O4/C core-shell nanorods show an initial lithium storage capacity of 1120 mAh/g and a reversible capacity of 394 mAh/g after 100 cycles, demonstrating better performance than that of the commercial graphite anode material.  相似文献   

8.

Composites of Co3O4/graphene nanosheets are prepared and characterized by X-ray diffraction and scanning electron microscopy. Their electrochemical behavior as anode materials of lithium-ion rechargeable batteries is investigated by galvanostatic discharge/charge measurements and cyclic voltammetry. The composite is composed of Co3O4 nanorods (around 20–40 nm in diameter) and nanoparticles (around 10 nm in diameter) distributed within the graphene matrix. The specific capacity of the composite is higher than both Co3O4 and graphene nanosheets. The cycling stability of Co3O4 is obviously enhanced by compositing with graphene. After 100 cycles, the discharge and charge capacity of the composite is 1,005 and 975 mAh g−1, respectively, and the irreversible capacity loss is less than 3%.

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9.
The demand for efficient and cheap electrochemical storage devices is very high today. Na-ion batteries are emerging as a promising alternative to Li-ion batteries for large-scale applications because of the much larger abundance of sodium. Among the different negative electrode materials allowing Na insertion at low potentials, hard carbons are the materials with the best electrochemical performances reported so far. Here we investigate the synthesis of hard carbons from tannins, an abundant and cheap bio-sourced carbon precursor made of polyphenolic molecules. We show that by a well-controlled synthesis method and high-temperature pyrolysis (1600°C), a hard carbon with developed ultra-microporosity is obtained. This hard carbon delivers a reversible capacity of 306 mAh g?1 at C/20 with a first-cycle coulombic efficiency of 87%. To our knowledge, these electrochemical performances are among the best ever reported in the literature for biomass-derived hard carbons.  相似文献   

10.
《中国化学快报》2023,34(4):107465
Sodium-ion batteries (SIB) have attracted widespread attention in large-scale energy storage fields owing to the abundant reserve in the earth and similar properties of sodium to lithium. Biomass-based carbon materials with low-cost, controllable structure, simple processing technology, and environmental friendliness tick almost all the right boxes as one of the promising anode materials for SIB. Herein, we present a simple novel strategy involving tea tomenta biomass-derived carbon anode with enhanced interlayer carbon distance (0.44 nm) and high performance, which is constructed by N,P co-doped hard carbon (Tea-1100-NP) derived from tea tomenta. The prepared Tea-1100-NP composite could deliver a high reversible capacity (326.1 mAh/g at 28 mA/g), high initial coulombic efficiency (ICE = 90% at 28 mA/g), stable cycle life (262.4 mAh/g at 280 mA/g for 100 cycles), and superior rate performance (224.5 mAh/g at 1400 mA/g). Experimental results show that the excellent electrochemical performance of Tea-1100-NP due to the high number of active N,P-containing groups, and disordered amorphous structures provide ample active sites and increase the conductivity, meanwhile, large amounts of microporous shorten the Na+ diffusion distance as well as quicken ion transport. This work provides a new type of N,P co-doped high-performance tomenta-derived carbon, which may also greatly promote the commercial application of SIB.  相似文献   

11.
Journal of Solid State Electrochemistry - The purplish-red rod-like crystal structure of novel bimetallic metal–organic-frameworks (MOF) {CoZn[(4,4′-BDA)(Phen)]2}n has been obtained by...  相似文献   

12.
Du N  Xu Y  Zhang H  Yu J  Zhai C  Yang D 《Inorganic chemistry》2011,50(8):3320-3324
A simple microemulsion-based method has been developed to synthesize ZnCo(2)(C(2)O(4))(3) nanowires that can be transformed to porous ZnCo(2)O(4) nanowires under annealing conditions. The morphology of porous ZnCo(2)O(4) nanowires can be tuned by the initial ZnCo(2)(C(2)O(4))(3) nanowires and the annealing temperatures. The as-synthesized porous ZnCo(2)O(4) nanowires have been applied as anode materials of Li-ion batteries, which show superior capacity and cycling performance. The porous one-dimensional (1D) nanostructures and large surface area are responsible for the superior performance. Moreover, it is indicated that porous ZnCo(2)O(4) nanowires synthesized at low annealing temperature (500 °C) show larger capacity and better cycling performance than that prepared at high annealing temperature (700 °C), because of their higher porosity and larger surface area.  相似文献   

13.
This work introduces an effective, inexpensive, and large-scale production approach to the synthesis of Fe2O3 nanoparticles with a favorable configuration that 5 nm iron oxide domains in diameter assembled into a mesoporous network. The phase structure, morphology, and pore nature were characterized systematically. When used as anode materials for lithium-ion batteries, the mesoporous Fe2O3 nanoparticles exhibit excellent cycling performance (1009 mA h g 1 at 100 mA g 1 up to 230 cycles) and rate capability (reversible charging capacity of 420 mA h g 1 at 1000 mA g 1 during 230 cycles). This research suggests that the mesoporous Fe2O3 nanoparticles could be suitable as a high rate performance anode material for lithium-ion batteries.  相似文献   

14.
A facile strategy was developed to prepare interlayer-expanded MoS2/graphene composites through a one-step hydrothermal reaction method. MoS2 nanosheets with several-layer thickness were observed to uniformly grow on the surface of graphene sheets. And the interlayer spacing of MoS2 in the composites was determined to expand to 0.95 nm by ammonium ions intercalation. The MoS2/graphene composites show excellent lithium storage performance as anode materials for Li-ion batteries. Through gathering advantages including expanded interlayers, several-layer thickness, and composited graphene, the composites exhibit reversible capacity of 1030.6 mAh g?1 at the current density of 100 mA g?1 and still retain a high specific capacity of 725.7 mAh g?1 at a higher current density of 1000 mA g?1 after 50 cycles.  相似文献   

15.
Silicon nanoparticles have been successfully inserted into graphene sheets via a novel method combining freeze-drying and thermal reduction. The as-obtained Si/graphene nanocomposite exhibits remarkably enhanced cycling performance and rate performance compared with bare Si nanoparticles for lithium-ion batteries.  相似文献   

16.
Carbon nanosprings (CNSs) with spring diameter of ~140 nm, carbon ring diameter of ~100 nm and pitch distance of ~150 nm, synthesized by using a catalytic chemical vapor deposition technology, have been investigated for potential applicability in lithium batteries as anode materials. The electrochemical results demonstrate that the present CNSs are superior anode materials for rechargeable lithium-ion batteries with high-rate capabilities, as well as long-term cycling life. At a current density as high as 3 A g?1, CNSs can still deliver a reversible capacity of 160 mA h g?1, which is about six times larger than that of graphite and three times larger than that of multi-wall carbon nanotubes under the same current density. After hundreds of cycles, there is no significant capacity loss for CNSs at both low and high current densities. The much improved electrochemical performances could be attributed to the nanometer-sized building blocks as well as the unusual spring-like morphology.  相似文献   

17.
18.
Liu  Yang  Su  Zhiqin  Wang  Yong  Shui  Jiaxin  Jin  Zhengfei  Bai  Bing  Qiu  Linlin  Du  Pingfan 《Journal of Solid State Electrochemistry》2023,27(4):969-976
Journal of Solid State Electrochemistry - Due to its high theoretical specific capacity and lower working potential, silicon is regarded as the most promising anode material for the new generation...  相似文献   

19.
Integrated analysis of the cycling parameters (reversible specific capacity, Coulomb efficiency, irreversible loss of cycle capacity, accumulated irreversible capacity, and retention of reversible capacity) of synthetic graphite of MAG brand as an active material for the negative electrode of lithium-ion batteries was made.  相似文献   

20.
Journal of Solid State Electrochemistry - Lithium iron silicate has caught tremendous attentions as an appealing cathode for future lithium-ion batteries due to high capacity, low cost, and...  相似文献   

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