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1.
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   

2.
Carbonaceous mesophase spherule (CMS) is a commercial anode material for rechargeable lithium batteries. A composite anode material of SnNi deposited carbonaceous mesophase spherule was prepared by co-precipitation method. The structural and electrochemical characterization of the SnNi/CMS composite anode material was studied. According to the measurement of its electrochemical characterization, the prepared SnNi/CMS composite anode material shows much better electrochemical performance than CMS. The first discharge capacity of 360 mA h g−1 was obtained for the SnNi/CMS composite anode material, and its discharge capacity maintained at 320–340 mA h g−1 in the following cycles. It indicates that the modification of CMS with SnNi alloy can further improve the intercalation performance of CMS. SnNi/CMS composite material shows a good candidate anode material for the commercial rechargeable lithium batteries.  相似文献   

3.
Ultrathin MoS2nanosheets were prepared in high yield using a facile and effective hydrothermal intercalation and exfoliation route. The products were characterized in detail using X-ray diffraction, scanning electron microscopy, transmission electron microscopy and Raman spectroscopy. The results show that the high yield of MoS2nanosheets with good quality was successfully achieved and the dimensions of the immense nanosheets reached 1 μm–2 μm. As anode material for Li-ion batteries, the as-prepared MoS2nanosheets electrodes exhibited a good initial capacity of 1190 mAh g-1and excellent cyclic stability at constant current density of 50 mA g-1. After 50 cycles, it still delivered reversibly sustained high capacities of 750 mAh g-1.  相似文献   

4.
Ultrathin MoS2nanosheets were prepared in high yield using a facile and effective hydrothermal intercalation and exfoliation route. The products were characterized in detail using X-ray diffraction, scanning electron microscopy, transmission electron microscopy and Raman spectroscopy. The results show that the high yield of MoS2nanosheets with good quality was successfully achieved and the dimensions of the immense nanosheets reached 1 μm–2 μm. As anode material for Li-ion batteries, the as-prepared MoS2nanosheets electrodes exhibited a good initial capacity of 1190 mAh g-1and excellent cyclic stability at constant current density of 50 mA g-1. After 50 cycles, it still delivered reversibly sustained high capacities of 750 mAh g-1.  相似文献   

5.
Porous MnO/C nanotubes are synthesized by a facile hydrothermal method followed by thermal annealing, and possess excellent cyclability and high rate capability as an anode for lithium ion batteries.  相似文献   

6.
Nickel foam-supported porous NiO film was prepared by a chemical bath deposition technique, and the NiO/polyaniline (PANI) film was obtained by depositing the PANI layer on the surface of the NiO film. The NiO film was constructed by NiO nanoflakes, and after the deposition of PANI, these nanoflakes were coated by PANI. As an anode for lithium ion batteries, the NiO/PANI film exhibits weaker polarization as compared to the NiO film. The specific capacity after 50 cycles for NiO/PANI film is 520 mAh g−1 at 1 C, higher than that of NiO film (440 mAh g−1). The improvement of these properties is attributed to the enhanced electrical conduction and film stability of the electrode with PANI.  相似文献   

7.
A novel porous Si/S-doped carbon composite was prepared by a magnesiothermic reaction of mesoporous SiO2, subsequently coating with a sulfur-containing polymer-poly(3,4-ethylene dioxythiophene), and a post-carbonization process. The as-prepared Si composite was homogeneously coated with disordered S-doped carbon with 2.6 wt.%?S in the composite and retained a high surface area of 58.8 m2?g?1. The Si/S-doped carbon composite exhibited superior electrochemical performance and long cycle life as an anode material in lithium ion cells, showing a stable reversible capacity of 450 mAh g?1 even at a high current rate of 6,000 mA?g?1.  相似文献   

8.
Nano-sized nickel ferrite (NiFe2O4) was prepared by hydrothermal method at low temperature. The crystalline phase, morphology and specific surface area (BET) of the resultant samples were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM) and nitrogen physical adsorption, respectively. The particle sizes of the resulting NiFe2O4 samples were in the range of 5–15 nm. The electrochemical performance of NiFe2O4 nanoparticles as the anodic material in lithium ion batteries was tested. It was found that the first discharge capacity of the anode made from NiFe2O4 nanoparticles could reach a very high value of 1314 mAh g−1, while the discharge capacity decreased to 790.8 mAh g−1 and 709.0 mAh g−1 at a current density of 0.2 mA cm−2 after 2 and 3 cycles, respectively. The BET surface area is up to 111.4 m2 g−1. The reaction mechanism between lithium and nickel ferrite was also discussed based on the results of cycle voltammetry (CV) experiments.  相似文献   

9.
We demonstrate for the first time that the reversible capacity of common natural graphite modified by catalytic oxidation can serve as an anode material for lithium ion batteries with above-theoretical capacity of graphite. The enhancement of reversible lithium capacity from 251 to >372 mAh g−1 results from an increase in the number of micropores and nanometer channels, which are formed by both chemical and catalytic oxidation. Lithium can also form alloys with metals used as oxidation catalysts, and these alloys may also contribute to the enhancement of reversible lithium capacity.  相似文献   

10.
Porous SnO2 nanotubes were prepared via electrospinning followed by calcination in air. As anode materials for lithium ion batteries, the porous nanotubes delivered a high discharge capacity of 807 mAh g? 1 after 50 cycles. Even after cycled at high rates, the electrode still retained a high fraction of its theoretical capacity. Such excellent performances of porous SnO2 nanotubes could be attributed to the porous and hollow structure which facilitated liquid electrolyte diffusion into the bulk materials and buffered large volume changes during lithium ions insertion/extraction. Furthermore, the nanoparticles of nanotubes provided the shorter diffusion length for lithium ions insertion which benefited in retaining the structural stability and good rate performance. Our results demonstrated that this simple method could be extended for the synthesis of porous metal oxide nanotubes with high performances in the applications of lithium ion batteries and other fields.  相似文献   

11.
A composite of silica (SiO2) and hard carbon was prepared by hydrothermal reaction. Special attention was paid to the characterization of the possible electrochemical reduction of nano-SiO2 in the composite. Evidence by solid-state nuclear magnetic resonance (NMR) and X-ray photoelectron spectroscopy (XPS) and high lithium storage capacity of the composite prove the electrochemical reduction of nano-SiO2 and the formation of Li4SiO4 and Li2O as well as Si in the first-discharge. The reversible lithium storage capacity of the nano-SiO2 is as high as 1675 mAh/g.  相似文献   

12.
Recently, the need of improvement of energy storage has led to the development of Lithium batteries with porous materials as electrodes. Porous Germanium (pGe) has shown promise for the development of new generation Li-ion batteries due to its excellent electronic, and chemical properties, however, the effect of lithium in its properties has not been studied extensively. In this contribution, the effect of surface and interstitial Li on the electronic properties of pGe was studied using a first-principles density functional theory scheme. The porous structures were modeled by removing columns of atoms in the [001] direction and the surface dangling bonds were passivated with H atoms, and then replaced with Li atoms. Also, the effect of a single interstitial Li in the Ge was analyzed. The transition state and the diffusion barrier of the Li in the Ge structure were studied using a quadratic synchronous transit scheme.  相似文献   

13.
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   

14.
TiO2 array film fabricated by potentiostatic anodization of titanium is characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and charge–discharge measurements. The XRD results indicated that the TiO2 array is amorphous, and after calcination at 500 °C, it has the anatase form. The pore size and wall thickness of TiO2 nanotube arrays synthesized at different anodization voltages are highly dependent on the applied voltage. The electrochemical performance of the prepared TiO2 nanotube array as an electrode material for lithium batteries was evaluated by galvanostatic charge–discharge measurement. The sample prepared at 20 V shows good cyclability but low discharge capacity of 180 mA h cm−3, while the sample prepared at 80 V has the highest discharge capacity of 340 mA h cm−3.  相似文献   

15.
Journal of Solid State Electrochemistry - The NaVO3 sample has been successfully fabricated via a simple sol-gel method adding Na2CO3 and V2O5 powders into distilled water with citric acid to act...  相似文献   

16.
Uniform α-Fe2O3 nanocapsules with a high surface area were synthesized by a novel wrap–bake–peel approach consisting of silica coating, heat treatment and finally the removal of the silica coating layer. The length, diameter and shell thickness of the hematite nanocapsules were about 65, 15 and 5 nm, respectively. The electrochemical properties of the α-Fe2O3 nanocapsules were investigated by cyclic voltammetry and charge/discharge measurements. The α-Fe2O3 nanocapsules showed a high reversible capacity of 888 mAh/g in the initial cycle and 740 mAh/g after 30 cycles as well as good capacity retention. This excellent electrochemical performance was attributed to the high surface area, thin shell and volume space of the hollow structure.  相似文献   

17.
SnS particles with sizes of 5.0–6.5 nm were prepared by a facile method. Resorcinol–formaldehyde sol with addition of the as-prepared SnS nanoparticles was spin-coated on a copper foil to prepare net-like SnS/C composite thin-film electrode for lithium ion batteries after carbonization at 650 °C. The SnS/C nanocomposite thin-film electrode showed preferable first coulombic efficiency and excellent cycling stability. The discharge and charge capacities were respectively 542.3 and 531.3 mAh/g after 40 cycles. The attractive electrochemical performances were mainly ascribed to the ultra fine particle, which showed no evident aggregation in high-resolution TEM image, and the effects of 3-dimensional net-like carbon structure, which uniformly surrounded the SnS nanoparticles to guarantee the contact, acted as a buffer matrix to alleviate the volume expansion of Li–Sn alloy and provided enough paths for electrolyte to reach SnS active material during discharge–charge process.  相似文献   

18.
The expanded graphite (BOCHEMIE a.s., Czech Republic) was tested as the material for anodes of lithium secondary batteries. The irreversible charge was lowered and the cyclability improved if the material was annealed in CO2. The specific capacity approached theoretical value corresponding to the composition LiC6.  相似文献   

19.
Here,an extremely cost-effective and simple method is proposed in order to morphologically selftransform stain less steel from a completely inactive material to a fully operati onal,nanowire-structured,3D anode material for lithium ion batteries.The reagentless process of a single heating step of the plain stainless steel in a partially reduci ng atmosphere,converts the stain less steel into an active anode via metal-selective oxidation,creating vast spinel-structured nanowires directly from the electrochemically in active surface.The simple process allows the complete utilizati on of the 3D mesh structure as the electrochemically-active spinel nanowires greatly enhance the active surface area.The novel material and architecture exhibits high capacities(-1000 mAh/g after-400 cycles),long cycle life(>1100 cycles)and fast rate performance(>2C).Simple modulation of the substrate can result in very high areal and volumetric capacities.Thus,areal capacities greater than 10 mAh/cm2 and volumetric capacities greater than 1400 mAh/cm3 can be achieved.Using the proposed method,the potential reduction in cost from the use of battery-grade graphite is at least an order of magnitude,with considerable better results achieved in terms of capacity and intrinsic structural benefits of the substrate,which include direct contact of the active material with the current collector,lack of delamination and binder-free performance.This work provides a new paradigm and a key step in the long route to replace the commercial graphite anode as the next-geneation anode material.  相似文献   

20.
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   

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