Anode Electrode For Lithium-ion Batteries Research Articles

SnO2 Quantum Dots@Graphene Framework as a High-Performance Flexible Anode Electrode for Lithium-Ion Batteries.

Three-dimensional (3D) layered tin oxide quantum dots/graphene framework (SnO2 QDs@GF) were designed through anchoring SnO2 QD on the graphene surface under the hydrothermal reaction. SnO2 QDs@GF have a 3D skeleton with a large number of mesopores and ultrasmall SnO2 QDs with a large surface area. The unique design of this structure improves the specific area and promotes ion transport. The mechanically strong SnO2 QDs@GF can directly be used as the anode of lithium-ion batteries (LIBs); it displays a high reversible capacity (1300 mA h g-1 at 100 mA g-1), excellent rate performance (642 mA h g-1 at 2000 mA g-1), and superior cyclic stability (when the current density is 10 A g-1, the capacity loss is less than 2% after 5000 cycles). This novel synthetic method can further be expanded for the production of other quantum dots/graphene composites with a 3D structure as high-performance electrodes for LIBs.

Ionic liquid-derivatized hierarchical N-doped carbon-coated Co3O4 nanosheet array as high-performance anode materials for lithium-ion batteries

A novel nitrogen-doped carbon-coated graded Co3O4 nanosheets (NDC/Co3O4 NS) is synthesized by using a simple ionic liquid hydrothermal method. The as-prepared NDC/Co3O4 NS is composed of hexagonal nanosheets having different orientation and the thickness of 50–100 nm. Significantly, as an anode electrode for lithium-ion batteries (LIBs), the NDC/Co3O4 NS performed excellent cyclability. The NDC/Co3O4 NS delivers an initial discharge capacity of 1281.4 mAh g−1 at 445 mA g−1 and maintains a reversible high capacity of 929.4 mAh g−1 after 50 cycles, much higher than the unmodified Co3O4 nanosheets (230 mAh g−1). The superior excellent electrochemical performance can be attributed to the gradient structure and the nitrogen-doped carbon coating resulting in shorter ion transport distances and good electrical conductivity.

Rice husk-derived carbon@SnO2@graphene anode with stable electrochemical performance used in lithium-ion batteries

In this study, we adopted a novel method to synthesize a rice husk-derived carbon@SnO2@reduced graphene oxide (rGO)composite with a multi-level structure as an anode electrode for lithium-ion batteries. The carbon source of composite was cellulose extracted from RH. The material exhibits excellent performance of LIBs with large reversible capacity and outstanding cycle performance. It shows a reversible capacity of 1206.9 mAhg−1 at a current density of 0.2C after 100 cycles. Excellent cycle performance is due to unique multi-level structure, which increases active site of lithium ion. Furthermore, SnO2 nanoparticles (SnO2 NPs) and carbon skeleton have strong chemical bonds to prevent SnO2 NPs from falling out of the three-dimensional network during cycling., thereby making material a promising anode material for LIBs.

Construction of the peanut-like Co3O4 as anode materials for high-performance lithium-ion batteries

Uniform peanut-like Co3O4 was synthesized by a simple solvothermal method using ethylene glycol and dethylene glycol as solvents, and polyvinylpyrrolidone as surfactant. Scanning electron microscope (SEM) and transmission electron microscope (TEM) proved that the obtained Co3O4 product has uniform size, and each of the peanut-like Co3O4 was made up of ultra-small nanoparticles. In consideration of the special structure, peanut-like Co3O4 was used as an anode electrode for lithium-ion batteries (LIBs), and which displayed satisfied electrochemical performance with high specific capacity (about 810 mA h g−1), long cyclability (700 mA h g−1 after 70 cycles), and a good rate performance.

Formation of Nitrogen‐Doped Carbon‐Coated CoP Nanoparticles Embedded within Graphene Oxide for Lithium‐Ion Batteries Anode

Due to its high electrochemical activities and low intercalation potential for Li/Li+, transition metal phosphides (TMPs) are booming as commerciogenic anode for lithium‐ion batteries (LIBs). Herein, the reasonable devise of nitrogen‐doped carbon‐coated CoP (CoP@NC) nanocomposites, which is derived from metal–organic frameworks (MOF‐Co) precursors, combining with graphene modification, is presented. The ultrafine CoP@NC nanoparticles are strongly incorporated with graphene networks (CoP@NC/GO). When assessed as anode electrode for LIBs, novel dual carbon encapsulation architectures of CoP@NC/GO hybrid composites exhibit superior cyclability (345 mAh g−1 at 1500 mA g−1 after 1000 cycles) and prominent rate ability (404 mAh g−1 at 3000 mA g−1). It is believed that this strategy can be helpful for boosting the electrochemical performance of the TMPs family as advance anode materials for energy storage systems.

Two-step synthesis of nanohusk Fe3O4 embedded in 3D network pyrolytic marine biochar for a new generation of anode materials for Lithium-Ion batteries

Two-step preparation of nanohusk Fe3O4 embedded in 3D network biochar was achieved by a facile slow pyrolysis process at 700 °C and hydrothermal gasification method. To reach material sustainability, a macroalga, namely Cladophora glomerata was used as carbon resource in this study. Based on structural characterizations by XRD, Raman, FTIR, FESEM, BET, and XPS analyses, it has been found that crystalline Fe3O4 particles are embedded in an amorphous olive shaped carbon matrix and created a 3D network carbon. When the 3D network carbon tested as an anode electrode in Lithium-Ion batteries (LIBs), showed a high initial specific discharge capacity of 1307 mAh g−1 at 100 mA g−1, good cycleability, and excellent rateability. Moreover, a stable reversible capacity of 551.7 mAh g−1 at 500 mA g−1 with the negligible capacity fade during charge and discharge process could be related to the high surface area, the presence of macro/meso porous structures, and iron crystals in 3D network carbon. Electrochemical Impedance Spectroscopy (EIS) and differential capacity analyses also showed the negligible decrease in Li+ diffusion coefficient and the safeguard the structural integrity of Fe3O4 by using carbon derived from biomass after charge and discharge processes.

Facile synthesis of MOF-derived hollow NiO microspheres integrated with graphene foam for improved lithium-storage properties

In this work, Ni-based metal-organic framework (MOF) hollow microspheres were firstly grown on the substrate of graphene foam (GF) by a facile solvothermal method, and then the NiO/GF composites were obtained after the calcination of Ni-MOF/GF precursors. The resulting NiO/GF could be employed as free-standing anode electrodes of lithium-ion batteries, showing superior specific capacities and cycling stabilities to pure NiO and GF. In detail, the optimized composite exhibited a capacity of 640 mAh g−1 after 50 cycles at 100 mA g−1. Even at a high current of 1 A g−1, the capacity still reached to ∼330 mAh g−1. The excellent electrochemical performance can be attributed to the synergistic effect between NiO and GF components. The GF matrix not only improves the conductivity of electrode, but also provides a flexible platform for the loading of active materials, preventing the escape and diffusion of NiO particles into the electrolyte during the cycling. Meanwhile, the well-defined hierarchical hollow structure of NiO in the composite effectively mitigates the volume change of metal oxides during the insertion/extraction reaction.

Electrophoretic deposition of carbon nanofibers/silicon film with honeycomb structure as integrated anode electrode for lithium-ion batteries

Silicon is considered to be one of the most promising substitutes for tradition graphite anode due to its highest theoretical specific capacity (4200 mAh g−1) in nature. However, the poor electronic conductivity and huge volume change during lithiation/delithiation process cause serious electrode polarization and the active particle cracking, resulting in significant capacity fading and therefore greatly limit their commercial application. Herein, we report a novel method—electrophoretic deposition (EPD) to prepare the CNFs/Si film with honeycomb structure as an integrated anode electrode without additional binders and conductive agents. The electrode film can be formed by the codeposition of CNFs and Si nanospheres onto the copper foil. Moreover, lithium tetraborate (Li2B4O7) has been proved to play a critical role on the structure and morphology of the electrode by influencing the migration rate and double electric layer of charged particles during the EPD process. As a result, the CNFs/Si electrode with nanosized Si particles homogeneously distributed in the CNFs matrix prepared by EPD method exhibits excellent capacity retention with a reversible capacity of 670 mAh g−1 after 100 cycles at a current density of 400 mA g−1 and good rate performance.

Spray-Drying-Induced Assembly of Skeleton-Structured SnO2/Graphene Composite Spheres as Superior Anode Materials for High-Performance Lithium-Ion Batteries.

Three-dimensional skeleton-structured assemblies of graphene sheets decorated with SnO2 nanocrystals are fabricated via a facile and large-scalable spray-drying-induced assembly process with commercial graphene oxide and SnO2 sol as precursors. The influences of different parameters on the morphology, composition, structure, and electrochemical performances of the skeleton-structured SnO2/graphene composite spheres are studied by XRD, TGA, SEM, TEM, Raman spectroscopy, and N2 adsorption-desorption techniques. Electrochemical properties of the composite spheres as the anode electrode for lithium-ion batteries are evaluated. After 120 cycles under a current density of 100 mA g-1, the skeleton-structured SnO2/graphene spheres still display a specific discharge capacity of 1140 mAh g-1. It is roughly 9.5 times larger than that of bare SnO2 clusters. It could still retain a stable specific capacity of 775 mAh g-1 after 50 cycles under a high current density of 2000 mA g-1, exhibiting extraordinary rate ability. The superconductivity of the graphene skeleton provides the pathway for electron transportation. The large pore volume deduced from the skeleton structure of the SnO2/graphene composite spheres increases the penetration of electrolyte and the diffusion of lithium ions and also significantly enhances the structural integrity by acting as a mechanical buffer.

Sb2O3 Nanoparticles Anchored on Graphene Sheets via Alcohol Dissolution-Reprecipitation Method for Excellent Lithium-Storage Properties.

Sb2O3 nanoparticles are uniformly anchored on reduced graphene oxide (rGO) sheets via a facile and ecofriendly route based on the alcohol dissolution-reprecipitation method. Such obtained Sb2O3/rGO composite demonstrates a highly reversible specific capacity (1355 mA h g-1 at 100 mA g-1), good rate capability, and superior life cycle (525 mA h g-1 after 700 cycles at 600 mA g-1) when used an anode electrode for lithium-ion batteries (LIBs). The outstanding electrochemical properties of Sb2O3/rGO composite could be attributed to its unique structure in which the strong electronic coupling effect between Sb2O3 and rGO leads to an enhanced electronic conductivity, structure stability, and electrochemical activity during reversible conversion-alloying reactions. Also, these findings are helpful in both developing novel high-performance electrodes for LIBs and synthesizing functional materials in an ecofriendly and economical way.

Fabrication of hierarchically branched SnO2 nanowires by two-step deposition method and their applications to electrocatalyst support and Li ion electrode

This paper reports hierarchically branched structures of tin dioxide nanowires for use in electrochemical energy conversion and storage electrode systems. The shallow tin dioxide branches are epitaxially grown on the tin dioxide nanowire backbones that are directly formed on current collectors. The branched tin dioxide nanowires are applied as anode electrodes for lithium-ion batteries, while palladium-incorporated branched nanowires are utilized as electrocatalysts for ethanol electrooxidation reactions. The structural benefits of these hierarchical platforms, such as enlarged electrochemical active surface area, void space formed between the branched structures, and conformal contact of the electroactive materials with current collectors, play important roles in improving the electrochemical Li-ion storage as well as electrocatalytic activity.

Preparation and enhanced lithium-ion storage performance of 3D network-like SnS2 anode

In present work, the three-dimensional (3D) sphere-like SnS2 and network-like SnS2 (the obtained samples respectively denoted as SnS2-SP and SnS2-NW) are successfully fabricated using a facile one-step process performed at low reaction temperature for a reduced time. It is found that the structure of the SnS2-NW prepared in a water-bath environment for 75 min is composed of self-assembled nanoflakes, the thickness of the cross-linked flakes is in a range of 5–10 nm. The layer spacing along the c-axis and specific surface area of SnS2-NW sample are larger than that of the SnS2-SP. When SnS2-SP and SnS2-NW materials are applied as anode electrodes of lithium-ion batteries (LIBs), the network-like SnS2 electrode exhibited high reversible capacity of 401.31 mA h g−1 after 100 cycles at 100 mA g−1, with a capacity loss of 0.5% per cycle. The SnS2-NW electrode can still retain a discharge capacity of 358.71 mA h g−1 with almost 99.7% coulombic efficiency even at 800 mA g−1, demonstrating excellent rate capacity and cycling performance, which are superior to that of the SnS2-SP electrode. The results demonstrate significant potential of SnS2-NW for application as anode of the LIBs.

Facile synthesis of hierarchical CoMn2O4 microspheres with porous and micro-/nanostructural morphology as anode electrodes for lithium-ion batteries

Hierarchical CoMn2O4 microspheres assembled by nanoparticles have been successfully synthesized by a facile hydrothermal method and a subsequent annealing treatment. XRD detection indicate the crystal structure. SEM and TEM results reveal the 3-dimensional porous and micro-/nanostructural microsphere assembled by nanoparticles with a size of 20-100 nm. The CoMn2O4 electrode show initial specific discharge capacity of approximately 1546 mAh/g at the current rates 100 mA/g with a coulombic efficiency of 66.7% and remarkable specific capacities (1029-485 mAh/g) at various current rates (100-2800 mA/g).

Formation and study of thin-film lithium-ion batteries using CNT/silicon composite material as an anode

An approach to the formation of new composite material of the anode electrode for lithium-ion batteries composed of carbon nanotubes (CNTs) synthesized on a substrate coated with a silicon layer has been studied. The dependence of the cyclicity and specific capacity of such a material on the geometric parameters of a CNT array has been studied. Using a CNT/silicon composite, the battery prototypes have been assembled and their characteristics and behavior during prolonged storage have been studied.

Synthesis of MnOx/reduced graphene oxide nanocomposite as an anode electrode for lithium-ion batteries

We report the high performance of the manganese oxide/reduced graphene oxide (MnOx/rGO) nanocomposite as an anode electrode of a lithium-ion battery. The composite is synthesized by a low temperature (83°C) chemical solution reaction, and shows relatively high specific capacities (660mAhg−1) after 50 cycles. For MnOx/rGO composites, the cycling stability is increased remarkably as compared to that seen with individual MnOx, and this is due to the synergistic effects of both the components in the composite. The rGO acts as a conductive buffer layer that suppresses the volume change of MnOx, and simultaneously promotes the conductivity of MnOx. The functional groups of graphene oxide facilitate MnOx formation at low temperature, and this retains the MnOx-graphene oxide connection, thus improving the capacity and cycling stability.

Flexible Bismuth Selenide /Graphene composite paper for lithium-ion batteries

A flexible Bi2Se3/Graphene (BSG) composite paper has been prepared through a simple vacuum filtration method and a thermal reduction together. The BSG composite paper was directly used as anode electrode for lithium-ion batteries, without using any polymer binders or conduction additives. In contrast to the pure Bi2Se3, the BSG exhibits high reversible lithium ion storage capacities and superior cyclic capacity retention. It proposed that the superior lithium storage performances would be attributed to the special construction of the as-prepared BSG paper, in which the graphene can not only act as conductive network for electrodes, but also act as a frame to alleviate volume expansion or aggregation of Bi2Se3 nanosheets during lithiation/delithiation. The as-prepared BSG paper shows a great potential as an anode materials for flexible Li-ion batteries.

The role of stable interface in nano-sized FeNbO4 as anode electrode for lithium-ion batteries

Nano-sized FeNbO4 (Nano-FNO) with an average diameter of 120nm is facilely prepared by co-precipitation method. Bulk FeNbO4 (Micro-FNO) as a comparison synthesized by conventional solid-state synthesis has an average grain size of 3–10μm. In the high-resolution transmission electron microscopy (HRTEM) images, Nano-FNO reveals an ordered single crystal structure, but Mirco-FNO is composed of disordered crystallites with different crystal orientation. Nano-FNO as anode material delivers the initial capacity of 475mAhg−1which is much higher than Micro-FNO electrode of 250mAhg−1.After dozens of charge/discharge cycles, the electrode of Nano-FNO remains the homogeneous combination with active material and conductive carbon, but the microcrystals in Micro-FNO electrode are cracked to small particles. The pulverization of Micro-FNO not only blocks the transfer of Li+ and electrons due to the separation between the active material and conductive carbon, but also results in the falling of active material from the current collector. Compared with the weakened electrochemical performances of Micro-FNO, Nano-FNO remains the excellent capacity after dozens of cycles. The charge transfer resistances of Nano-FNO and Micro-FNO after several cycles are further studied by fitting their electrochemical impedance spectra.

A New Approach of the Synthesis of SiO2 Nanowires By Using Bulk Copper Foils As Catalyst

Silica nanowires (SiO2NWs) have attracted considerable attention over the last decades due to their diverse properties and broad range of applications. Among them, it is well-known the capacity of SiO2NWs to emit strong blue light. It is also widely recognized the versatility of this material as biosensor, since it can be easily functionalized in order to respond to several targets. Other applications include their potential use as anode electrode for lithium-ion batteries, or as protective layer against corrosion by exposure to the environment. In this regard, the use of a metal substrate is of paramount relevance; therefore, an adequate contact between the substrate and the nanostructures is required. Especially numerous and varied are the procedures for the growth of SiO2NWs, being one of the most employed the so-called vapor-liquid-solid (VLS) method. By this mechanism, the nanowires grow from a metal nanoparticle when the adequate gaseous precursor is added. However, the main drawback of this mechanism resides in the need of a Si substrate for the synthesis of the SiO2NWs. Apart from the original Au-Si system, a broad variety of other metals such as Fe, Co, Ni or Cu may act as catalysts for the growth. Particularly, of special interest is the case of copper, which is present in a large majority of electronic devices. Furthermore, the Cu–Si phase diagram shows a eutectic point at 802 ⁰C (16 wt% of silicon) promoting the formation of a liquid alloy at an accessible temperature for a relatively low concentration of silicon in copper. This work presents a novel procedure for the growth of SiO2 nanowires directly from polycrystalline copper foils. The single-step synthesis procedure consists of a thermal treatment at 900 ◦C without the need for additional catalysts. As a result, nanowires with an average diameter of 100 nm are synthesized. A systematic study undertaken at different stages of the SiO2NWs growth confirmed the generation of nucleation centers on the Cu surface as well as revealed the existence of an intermediate gaseous SiO species at the synthesis temperature, which promotes the growth of the SiO2NWs via a VLS mechanism. Figure 1 shows the dark field scanning transmission electron microscopy (DF-STEM) image of the as-synthesized SiO2NWs. As can be seen there, SiO2NWs growth is generated from substrate protrusions of around 200 nm in diameter, exceling from the Cu substrate. These protuberances produced during the thermal treatment could be the evidence of the formation of Cu-Si alloys required as initial step for generating the SiO2NWs. Figure 2a shows the detail of a protrusion of the Cu substrate (in bright contrast) just under the nanowire (in dark contrast). EDX elemental maps performed on the inset area confirms the presence of Cu at the bottom of the nanowire (Fig 2b). Meanwhile, Figs 2c and 2d show a homogeneous distribution of Si and O across the whole nanowire. This process with bulk Cu foils as catalytic agent allows the growth of SiO2NWs over metallic substrates, granting an adequate interconnection between both surfaces. Figure 1

ZnO Nanocrystals as Anode Electrodes for Lithium-Ion Batteries

ZnO nanocrystals were synthesized via a thermal decomposition method. X-ray diffraction, transmission electron microscopy, and photoluminescence were used to investigate the composition and nanostructure of the material. Compared with commercial ZnO nanoparticles, ZnO nanocrystals showed higher lithium storage capacity and better cycling characteristics and exhibited a reversible discharge capacity of 500 mAh g−1after 100 cycles at 200 mA g−1.

Controlled synthesis of mesoporous nanostructured anatase TiO2on a genetically modified Escherichia coli surface for high reversible capacity and long-life lithium-ion batteries

Deposition and mineralization of TiO2on genetically modifiedEscherichia colisurface has been achieved, leading to formation of a nanostructured anatase TiO2with enhanced electrochemical performance as anode electrodes of lithium-ion batteries.