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1.
A sulfur-substituted disordered carbon is explored as anode material for lithium-ion battery. Its physical and electrochemical properties are characterized by a variety of techniques such as powder X-ray diffraction, element analysis, Fourier transform infrared spectrum, scanning electron microscopy, and typical electrochemical tests. Electrochemical tests show the activated carbon displays a first cycle discharge capacity of 1,216 mAh·g−1. It also has a remarkable cycling stability with an average capacity fade of 0.92% per cycle from 11th to 100th cycle in the range of 0.01–3.00 V versus metallic lithium at a current density of 100 mA·g−1. After 100 cycles, the electrode still maintained a capacity of 420 mAh·g−1.  相似文献   

2.
A new SnO_2-Fe_2O_3/SWCNTs(single-walled carbon nanotubes) ternary nanocomposite was first synthesized by a facile hydrothermal approach.SnO_2 and Fe_2O_3 nanoparticles(NPs) were homogeneously located on the surface of SWCNTs,as confirmed by X-ray diffraction(XRD),transmission electron microscope(TEM) and energy dispersive X-ray spectroscopy(EDX).Due to the synergistic effect of different components,the as synthesized SnO_2-Fe_2O_3/SWCNTs composite as an anode material for lithium-ion batteries exhibited excellent electrochemical performance with a high capacity of 692 mAh·g~(-1) which could be maintained after 50 cycles at 200 mA·g~(-1).Even at a high rate of2000 mA·g~(-1),the capacity was still remained at 656 mAh·g~(-1).  相似文献   

3.
Journal of Solid State Electrochemistry - Ta2O5 is one of the promising anode materials for lithium ion battery application undergoing conversion reaction in combination with an extrinsic...  相似文献   

4.
Nb2O5-carbon nanocomposite is synthesized through a facile one-step hydrothermal reaction from sucrose as the carbon source, and studied as an anode material for high-performance lithium ion battery. The structural characterizations reveal that the nanocomposite possesses a core-shell structure with a thin layer of carbon shell homogeneously coated on the Nb2O5 nanocrystals. Such a unique structure enables the composite electrode with a long cycle life by preventing the Nb2O5 from volume change and pulverization during the charge-discharge process. In addition, the carbon shell efficiently improves the rate capability. Even at a current density of 500 mA·g?1, the composite electrode still exhibits a specific capacity of ~100 mAh·g?1. These results suggest the possibility to utilize the Nb2O5-carbon core-shell composite as a high performance anode material in the practical application of lithium ion battery.  相似文献   

5.
Anatase TiO2 nanotube was doped with different contents of Sn (3, 5, and 7 at.%) through sol-gel method and subsequent hydrothermal process. X-ray diffraction (XRD), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), field emission scanning electron microscopy (FESEM), high-resolution transmission electron microscopy (HRTEM), Brunauer-Emmett-Teller (BET), and Hall effect measurement are utilized to characterize the structures, components, chemical environments, morphologies, specific areas, and electronic conductivities of the samples. The investigation in cycling performances demonstrates that 5 at.% Sn-doped TiO2 nanotube exhibits the best cycling stability, with specific capacity of 386 mAh g?1 and coulombic efficiency of 99.2 % after 50 cycles at 0.1 C, much higher than those of the other Sn-doped samples and pristine TiO2 nanotube. The improved electrochemical performances of Sn-doped TiO2 nanotube are attributed to the increase of electronic conductivity and therefore enhance the reversible capacity of the material.  相似文献   

6.
A new SnO_2-Fe_2O_3/SWCNTs(single-walled carbon nanotubes) ternary nanocomposite was first synthesized by a facile hydrothermal approach.SnO_2 and Fe_2O_3 nanoparticles(NPs) were homogeneously located on the surface of SWCNTs,as confirmed by X-ray diffraction(XRD),transmission electron microscope(TEM) and energy dispersive X-ray spectroscopy(EDX).Due to the synergistic effect of different components,the as synthesized SnO_2-Fe_2O_3/SWCNTs composite as an anode material for lithium-ion batteries exhibited excellent electrochemical performance with a high capacity of 692 mAh·g~(-1) which could be maintained after 50 cycles at 200 mA·g~(-1).Even at a high rate of2000 mA·g~(-1),the capacity was still remained at 656 mAh·g~(-1).  相似文献   

7.
Tremella-like structured MoO2 consisting of nanosheets was obtained via a Fe2O3-assisted hydrothermal reduction of MoO3 in ethylenediamine aqueous solution. The as-prepared product was characterized and tested with scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray powder diffraction (XRD), X-ray photoelectron spectroscopy (XPS), cyclic voltammetry (CV) and capacity measurement as anode material for lithium ion batteries. This structured MoO2 shows very high reversible capacity (>600 mA h g−1), good rate capability and cycling performance, presenting potential application as anode material for lithium ion batteries with high rate capability and high capacity.  相似文献   

8.
A new strategy was applied to synthesise a porous nanostructure of α-Fe(2)O(3) xerogel assembled from nanocrystalline particles (~5 nm) with abundant mesopores (~3 nm) using a hydrothermal method. The α-Fe(2)O(3) xerogel exhibits excellent cycling performance (up to 1000 cycles) and rate capability (reversible discharging capacity 280 mAh g(-1) at 10 C) as a potential anode for high power lithium-ion batteries.  相似文献   

9.
In this work,via a facile solvothermal route,we synthesized an anode material for lithium ion batteries(LIBs)—SnS_2 nanoparticle/graphene(SnS_2 NP/GNs) nanocomposite.The nanocomposite consists of SnS_2nanoparticles with an average diameter of 4 nm and graphene nanosheets without restacking.The SnS_2 nanoparticles are firmly anchored on the graphene nanosheets.As an anode material for LIBs,the nanocomposite exhibits good Li storage performance especially high rate performance.At the high current rate of 5,10,and 20 A/g,the nanocomposite delivered high capacities of 525,443,and 378 mAh/g,respectively.The good conductivity of the graphene nanosheets and the small particle size of SnS_2contribute to the electrochemical performance of SnS_2 NP/GNs.  相似文献   

10.
An ordered mesoporous carbon-silica-titania material was prepared using the tetra-constituents co-assembly method. As regards its anode performance in lithium ion batteries, the composite material anode exhibited a high capacity (875 mAh g(-1)), a higher initial efficiency (56%) and an improved rate.  相似文献   

11.
Here we demonstrate for the first time a novel kind of anode material with low sensitivity to water, which consists of natural graphite and deposited copper. Through measurement of X-ray photoelectron spectroscopy, thermogravimetric and differential thermal analysis and high resolution electron microscopy, it is found that copper exists at the surface of natural graphite in the forms of metallic copper and copper carbides. Since the deposited copper covers and removes some active sites at the surface of natural graphite, which absorbs water relatively easily, cycling behavior in the presence of high humidity (1000 ppm H2O) is improved much. Concomitantly, reversible capacity enhances due to alloying of copper with lithium.  相似文献   

12.
InP thin film has been successfully fabricated by pulsed laser deposition (PLD) and was investigated for its electrochemistry with lithium for the first time. InP thin film presented a large reversible discharge capacity around 620 mAh g?1. The reversibility of the crystalline structure and electrochemical reaction of InP with lithium were revealed by using ex situ XRD and XPS measurements. The high reversible capacity and stable cycle of InP thin film electrode with low overpotential made it one of the promise energy storage materials for future rechargeable lithium batteries.  相似文献   

13.
Journal of Solid State Electrochemistry - Porous FeP@C networks are realized via a one-step calcination process, using ferric nitrate and phytic acid as the precursors of FeP along with thiourea...  相似文献   

14.
15.
以金属氯化物为金属源,硫脲为硫源,聚乙二醇和乙二醇为混合溶剂,采用溶剂热法一步合成了球形的铜锌锡硫纳米颗粒.利用X射线衍射仪(XRD),扫描电子显微镜(SEM)和透射电子显微镜(TEM)分析了铜锌锡硫纳米颗粒的物相、结构、形貌;利用电池测试系统对以铜锌锡硫纳米颗粒为锂离子电池负极材料组装的锂离子电池的电化学性能进行了测试.结果表明:所得到的产物为具有锌黄锡矿结构的纯相铜锌锡硫,颗粒直径在300~500nm.铜锌锡硫纳米颗粒作为锂离子电池的负极材料具有较好的稳定性,有望在锂离子电池研究和应用中得到推广.  相似文献   

16.
Mb2O5 -carbon nanocomposite is synthesized through a facile one-step hydrothermal reaction from sucrose as the carbon source,and studied as an anode material for high-performance lithium ion battery.The structural characterizations reveal that the nanocomposite possesses a core-shell structure with a thin layer of carbon shell homogeneously coated on the Nb2O5 nanocrystals.Such a unique structure enables the composite electrode with a long cycle life by preventing the Nb2O5 from volume change and pulverization during the charge-discharge process. In addition,the carbon shell efficiently improves the rate capability.Even at a current density of 500 mA·g-1,the composite electrode still exhibits a specific capacity of~100 mAh·g-1.These results suggest the possibility to utilize the Nb2O5-carbon core-shell composite as a high performance anode material in the practical application of lithium ion battery.  相似文献   

17.
Three-dimensionally (3D) ordered mesoporous titania (anatase) microparticles without substrate were prepared by using polystyrene (PS) colloidal crystal as a template and characterized by transmission electron microscopy, X-ray diffraction, thermogravimetry and electrochemical measurement. As anode materials for lithium ion battery, they present eximious kinetic performance and good capacity retention due to their special architecture with mesoporous channels and thin walls, which are beneficial to the diffusion of lithium ions. Besides, mixing 3D ordered mesoporous titania microparticles with conductive additive can reduce the resistance of the anode, favor the mobility of the electrons, and decrease the polarization.  相似文献   

18.
Using a commercially available LiCoO2 as starting material, a surface-modified cathode material was obtained by coating it with a nano layer of amorphous carbon. The carbon-coated LiCoO2 was characterized by X-ray diffraction analysis, scanning electronic microscopy, transmission electronic microscopy, electrochemical impedance spectroscopy and measurement of charge/discharge behavior. Results show that the carbon-coated LiCoO2 displays marked lower charge transfer resistance, higher lithium ion diffusion coefficient and much better rate capability than the original LiCoO2. It also indicates promising application of lithium ion batteries in the areas requiring charge and discharge at high rate.  相似文献   

19.
TiO2 nanotubes prepared by using a hydrothermal process were firstly coated with silver nanoparticles as the anode materials for lithium–ion batteries by the traditional silver mirror reaction. The physical properties of the as-synthesized samples were investigated by X-ray diffraction and transmission electron microscopic. The as-prepared samples were used as negative materials for lithium–ion battery, whose charge–discharge properties, cyclic voltammetry, electrochemical impedance spectroscopy and cycle performance were examined in detail. The results showed that the Ag additive decreased the polarization of anode, and marvelously improved the high-rate discharge capacity and cycling stability of TiO2 nanotubes.  相似文献   

20.
Nb2O5/C nanosheets are successfully prepared through a mixing process and followed by heating treatment.Such Nb2O5/C based electrode exhibits high rate performance and remarkable cycling ability, showing a high and stable specific capacity of ~380 mAh g-1 at the current density of 50 mA g-1(much higher than the theoretical capacity of Nb2O5).Further more,at a current density of 500 mA g-1,the nanocomposites electrode still exhibits a specific capacity of above 150 mAh g-1 after 100 cycles.These results suggest the Nb2O5/C nanocomposite is a high performance anode material for lithium-ion batteries.  相似文献   

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