Superior lithium storage performance in MoO3 by synergistic effects:Oxygen vacancies and nanostructures

Molybdenum trioxide(MoO₃) has recently attracted wide attention as a typical conversion-type anode of Li-ion batteries(LIBs).Nevertheless,the inferior intrinsic conductivity and rapid capacity fading during charge/discharge process seriously limit large-scale commercial application of MoO₃.Herein,the density function theory(DFT) calculations show that electron-proton co-doping preferentially bonds symmetric oxygen to form unstable H_xMoO₃.When the-OH-gr...     

Enhanced electrochemical performance of MoS2 anode material with novel composite binder

Journal of Solid State Electrochemistry - A simple and green approach for creating a highly capacitive molybdenum disulphide (MoS2) anode material for lithium-ion batteries is proposed. The...     

Reversible lithium storage in Na2Li2Ti6O14 as anode for lithium ion batteries

The sodium lithium titanate with composition Na₂Li₂Ti₆O₁₄ has been synthesized by a sol–gel method. Thermogravimetric analysis and differential thermal analysis (TG–DTA) of the thermal decomposition process of the precursor and X-ray diffraction (XRD) data indicate the crystallization of sodium lithium titanate has occurred at about 600 °C. Electrochemical lithium insertion into Na₂Li₂Ti₆O₁₄ for lithium ion battery has been investigated for the first time. These results indicate the discharge and charge potential plateaus are about 1.3 V. The initial discharge capacity is much higher than the charge capacity and irreversible capacity exists in the voltage window 1–3 V. Subsequently, the discharge capacity decreases slowly, but the charge capacity increases slightly in the following cycles. After a few cycles, the specific capacity remains almost constant values and the sample exhibits the excellent retention of capacity on cycling.     

Reaction mechanism and additional lithium storage of mesoporous MnO_2 anode in Li batteries

Nanostructured transition metal oxides,employed as anode materials for lithium-ion batteries,exhibit a higher capacity than the theoretical capacity based on the conversion reaction.To date,the reasons behind this phenomenon are unclear.For the one-step evolution of anode material for lithium-ion batteries,it is essential to understand the lithium storage reaction mechanism of the anode material.Herein,we provide a detailed report on the lithium storage and release mechanism of MnO2,using synchrotron-based X-ray techniques.X-ray diffraction and X-ray absorption spectroscopy results indicate that during the first discharge,MnO2 is reduced in the order of MnO2→LixMnO2(1相似文献   

SnO2 nanocrystal-Fe2O3 nanorod hybrid structures: an anode material with enhanced lithium storage capacity

Journal of Solid State Electrochemistry - Through a two-step hydrothermal method, we synthesized a metal-oxide heterostructure composed of SnO2 nanocrystals (NCs) with a diameter of...     

SnO_2 nanospheres among GO and SWNTs networks as anode for enhanced lithium storage performances

Conducting supporters of purified single-walled carbon nanotubes(SWNTs) and graphene oxide(GO)were used to confine pomegranate-structured Sn O2 nanospheres for forming SnO_2-GO-SWNT composites.As anode material for lithium ion batteries(LIBs), this composite exhibits a stable and large reversible capacity together with an excellent rate capability. In addition, an analysis of the AC impedance spectroscopy has been used to confirm the enhanced mechanism for LIB performance. The improved electrochemical performance should be ascribed greatly to the reinforced synergistic effects between GO and SWNT networks, and their enhanced contribution of the conductivity. These results indicate that this composite has potential for utilization in high-rate and durable LIBs.     

Lithium storage performance of Sn-MOF-derived SnO2 nanospheres as anode material

Journal of Solid State Electrochemistry - In this work, a spherical Sn-MOF precursor was synthesized through hydrothermal method using 1,3,5-benzenetricarboxylic acid (H3BTC) as the organic ligand....     

MOF-derived ZnO/ZnFe2O4@RGO nanocomposites with high lithium storage performance

ZnO/ZnFe₂O₄@reduced graphene oxide (RGO) nanocomposites have been successfully synthesized through annealing treatment of Zn/Fe MOF-5@GO composites. The ZnO/ZnFe₂O₄ nanoparticles with a diameter of 12–15 nm are evenly distributed on the surface of RGO. The ZnO/ZnFe₂O₄@RGO nanocomposites show superior rate capacity and cyclic stability of 655 mAh/g after 200 cycles at 0.2 A/g for lithium ion battery (LIB) anode. The superior electrochemical property benefits from the unique structure of ZnO/ZnFe₂O₄@RGO nanocomposites, which can provide a buffer space for volume expansion, and enhance conductivity in the charge/discharge cycle.

     

Improved electrode fabrication method to enhance performance and stability of MoS2-based lithium-ion battery anode

Choice of binder and the electrode-making process play a pivotal role in the electrochemical performance of MoS₂, when used as lithium-ion battery anode. In this work, MoS₂ nanorods are prepared by gas phase synthesis method using molybdenum trioxide (MoO₃) nanobelts and sulfur as starting materials. It has been observed that by tuning the reaction conditions, morphology and yield of the final product can be controlled. Carboxymethyl cellulose (CMC) is used as binder to fabricate the MoS₂ electrode, and its electrochemical performance is tested against Li/Li⁺. The performance of electrode can be further improved by incorporating heat treatment to the active material and conductive carbon mixture prior to electrode fabrication. The electrochemical data shows that the optimum temperature for heat treatment is 700 °C. In the current report, we would like to elucidate a detailed study based on electrode fabrication process and their impact on the electrochemical performance.     

Enhanced electrochemical performance and mechanism study of AgLi1/3Sn2/3O2 for lithium storage

Herein, AgLi_1/3Sn_2/3O₂ with delafossite structure was prepared by treating the layered compound Li₂SnO₃ with molten AgNO₃ via ion exchange of Li⁺ for Ag⁺. The structure characterization and the electrochemical performance of AgLi_1/3Sn_2/3O₂ was thoroughly investigated. AgLi_1/3Sn_2/3O₂ is found to possess stacking lamellar morphology, which means small electrochemical impedance and so facilitates charge transfer kinetics during the cycling. Compared with Li₂SnO₃, due to the introducing of excellent electrical conductivity of silver, AgLi_1/3Sn_2/3O₂ exhibits improved electrochemical performance in terms of capacity, cycling stability and coulombic efficiency. The results show AgLi_1/3Sn_2/3O₂ presents favorable specific capacity of 339 mAh/g at current density of 200 mA/g after 50 cycles and initial coulombic efficiency of 96%. Ex situ XRD analysis revealed the reaction mechanism of AgLi_1/3Sn_2/3O₂ as an anode for lithium ion batteries.     

A unique hierarchical composite with auricular-like MoS2 nanosheets erected on graphene for enhanced lithium storage

Journal of Solid State Electrochemistry - Molybdenum disulfide (MoS2) is a promising anode material in lithium-ion batteries (LIBs) due to its high specific capacity and typical two-dimensional...     

Porous SnO2/layered titanate nanohybrid with enhanced electrochemical performance for reversible lithium storage

A porous hybrid of titanate nanosheets with SnO(2) nanoparticles has been realized by an exfoliation and reassembling route. The present nanohybrid shows a large reversible capacity of 860 mA h g(-1) with a good capacity retention (about 60% retention of the initial capacity after 50 cycles).     

In situ synthesis of MoS2/graphene nanosheet composites with extraordinarily high electrochemical performance for lithium ion batteries

A facile process was developed to synthesize MoS(2)/graphene nanosheet (GNS) composites by a one-step in situ solution-phase method. These MoS(2)/GNS composites therefore exhibit extraordinary capacity, i.e., up to 1300 mA h g(-1), and excellent rate capability and cycling stability as an anode material for lithium ion batteries.     

Phosphatization: A promising approach to enhance the performance of mesoporous TiO2 anode for lithium ion batteries

We report phosphatization is a promising method to enhance the performance of mesoporous TiO₂ anode for lithium ion batteries. The resulting phosphated mesoporous TiO₂ possessed higher reversible capacity and better cycling stability than the pure mesoporous TiO₂. When cycled at 30 mA/g between 3.0 and 1.0 V, the initial capacity of phosphate mesoporous TiO₂ was 249 mA h/g, significantly higher than that of pure mesoporous TiO₂ (204 mA h/g). After 40 cycles, the capacity retention ratio of phosphate mesoporous TiO₂ reached 83.7%, while pure mesoporous TiO₂ had merely a capacity retention ratio of 62.3%. We believe that this phosphatization process could be used to enhance the electrochemical performance of other metal oxides for lithium ion batteries.     

Dual-metal zeolite imidazolate framework for efficient lithium storage boosted by synergistic effects and self-assembly 2D nanosheets

Metal-organic framework materials(MOFs), such as zeolitic imidazolate framework(ZIF), have been widely used in energy storage due to their advantages such as high structural stability, large specific surface, more active sites and skeleton structures. Herein, a novel two-dimensional(2D) Co Cu-ZIF was synthesized by a facile solvothermal method. The as-prepared Co Cu-ZIF nanosheets exhibit an ultrahigh reversible capacity of 2287.4 m Ah/g and remains at 1172.1 m Ah/g after 300 cycles at a current...     

Lithium storage in hollow spherical ZnFe2O4 as anode materials for lithium ion batteries

Hollow microspheres composed of phase-pure ZnFe₂O₄ nanoparticles (hierarchically structured) have been prepared by hydrothermal reaction. The unique hollow spherical structure significantly increases the specific capacity and improves capacity retention of this material. The product of each phase transition during initial discharge (ZnFe₂O₄ ? Li_0.5ZnFe₂O₄ ? Li₂ZnFe₂O₄ → Li₂O + Li–Zn + Fe) and their structural reversibility are recognized by X-ray diffraction and electrochemical characterization. The products of the deeply discharged (Li–Zn alloy and Fe) and recharged materials (Fe₂O₃) were clarified based on high resolution transmission electron microscopic technique and first-principle calculations.     

Nanosheet-assembled MoS2/Ni3S2 microspheres for flexible energy storage devices

Journal of Solid State Electrochemistry - Two-dimensional transition metal sulfides (TMDs) possess various morphologies and microstructures, which are widely used in the field of supercapacitors....     

Fabrication of Nb2O5/C nanocomposites as a high performance anode for lithium ion battery

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.     

Hydrothermal carbon spheres containing silicon nanoparticles: synthesis and lithium storage performance

Spherically shaped carbon/silicon nanocomposites have been obtained in a one-step procedure using hydrothermal carbonization of glucose in the presence of commercially available silicon nanoparticles and have been tested electrochemically as an anode material for lithium-ion batteries.