Carbon-coated SnO2 riveted on a reduced graphene oxide composite (C@SnO2/RGO) as an anode material for lithium-ion batteries

The research on graphene-based anode materials for high-performance lithium-ion batteries (LIBs) has been prevalent in recent years. In the present work, carbon-coated SnO₂ riveted on a reduced graphene oxide sheet composite (C@SnO₂/RGO) was fabricated using GO solution, SnCl₄, and glucose via a hydrothermal method after heat treatment. When the composite was exploited as an anode material for LIBs, the electrodes were found to exhibit a stable reversible discharge capacity of 843 mA h g⁻¹ at 100 mA g⁻¹ after 100 cycles with 99.5% coulombic efficiency (CE), and a specific capacity of 485 mA h g⁻¹ at 1000 mA g⁻¹ after 200 cycles; these values were higher than those for a sample without glucose (SnO₂/RGO) and a pure SnO₂ sample. The favourable electrochemical performances of the C@SnO₂/RGO electrodes may be attributed to the special double-carbon structure of the composite, which can effectively suppress the volume expansion of SnO₂ nanoparticles and facilitate the transfer rates of Li⁺ and electrons during the charge/discharge process.

The combined action of GO and glucose makes the SnO₂ dispersed uniformly. The synergistic effect of the unique double-carbon structure can effectively improve the electrical conductivity of the SnO₂ and strengthen lithium storage capability.

Tin dioxide-based nanomaterials as anodes for lithium-ion batteries

The development of new electrode materials for lithium-ion batteries (LIBs) has attracted significant attention because commercial anode materials in LIBs, like graphite, may not be able to meet the increasing energy demand of new electronic devices. Tin dioxide (SnO2) is considered as a promising alternative to graphite due to its high specific capacity. However, the large volume changes of SnO2 during the lithiation/delithiation process lead to capacity fading and poor cycling performance. In this review, we have summarized the synthesis of SnO2-based nanomaterials with various structures and chemical compositions, and their electrochemical performance as LIB anodes. This review addresses pure SnO2 nanomaterials, the composites of SnO2 and carbonaceous materials, the composites of SnO2 and transition metal oxides, and other hybrid SnO2-based materials. By providing a discussion on the synthesis methods and electrochemistry of some representative SnO2-based nanomaterials, we aim to demonstrate that electrochemical properties can be significantly improved by modifying chemical composition and morphology. By analyzing and summarizing the recent progress in SnO2 anode materials, we hope to show that there is still a long way to go for SnO2 to become a commercial LIB electrode and more research has to be focused on how to enhance the cycling stability.

A MoS2@SnS heterostructure for sodium-ion storage with enhanced kinetics

Layered metal sulphides are promising anode materials for sodium-ion batteries (SIBs) and capacitors owing to their distinctive crystal structures and large interlayer spacings, which are suitable for Na⁺ insertion/extraction. However, low electronic conductivity, sluggish ion transfer and large volume variation of metal sulphides during sodiation/desodiation processes have hindered their practical application. In this work, we report the construction of a walnut-like core-shell MoS₂@SnS heterostructure composite as an anode for SIBs with high capacity, remarkable rate and superior cycling stability. Experimental observations and first-principles density functional theory (DFT) calculations reveal that the enhanced electrochemical performances can be mainly ascribed to the boosted charge transfer and ion diffusion capabilities at the heterostructure interface driven by a self-building internal electric field. Our findings herein may pave the way for the development of novel heterostructure composite materials for beyond lithium-ion batteries and capacitors.

Large Scale Process for Low Crystalline MoO₃-Carbon Composite Microspheres Prepared by One-Step Spray Pyrolysis for Anodes in Lithium-Ion Batteries

This paper introduces a large-scale and facile method for synthesizing low crystalline MoO₃/carbon composite microspheres, in which MoO₃ nanocrystals are distributed homogeneously in the amorphous carbon matrix, directly by a one-step spray pyrolysis. The MoO₃/carbon composite microspheres with mean diameters of 0.7 µm were directly formed from one droplet by a series of drying, decomposition, and crystalizing inside the hot-wall reactor within six seconds. The MoO₃/carbon composite microspheres had high specific discharge capacities of 811 mA h g-1 after 100 cycles, even at a high current density of 1.0 A g-1 when applied as anode materials for lithium-ion batteries. The MoO₃/carbon composite microspheres had final discharge capacities of 999, 875, 716, and 467 mA h g-1 at current densities of 0.5, 1.5, 3.0, and 5.0 A g-1, respectively. MoO₃/carbon composite microspheres provide better Li-ion storage than do bare MoO₃ powders because of their high structural stability and electrical conductivity.

Coral-Like Yolk-Shell-Structured Nickel Oxide/Carbon Composite Microspheres for High-Performance Li-Ion Storage Anodes

In this study, coral-like yolk-shell-structured NiO/C composite microspheres (denoted as CYS-NiO/C) were prepared using spray pyrolysis. The unique yolk-shell structure was characterized, and the formation mechanism of the structure was proposed. Both the phase separation of the polyvinylpyrrolidone and polystyrene (PS) colloidal solution and the decomposition of the size-controlled PS nanobeads in the droplet played crucial roles in the formation of the unique coral-like yolk-shell structure. The CYS-NiO/C microspheres delivered a reversible discharge capacity of 991 mAh g^-1 after 500 cycles at the current density of 1.0 A g^-1. The discharge capacity of the CYS-NiO/C microspheres after the 1000th cycle at the current density of 2.0 A g^-1 was 635 mAh g^-1, and the capacity retention measured from the second cycle was 91%. The final discharge capacities of the CYS-NiO/C microspheres at the current densities of 0.5, 1.5, 3.0, 5.0, 7.0, and 10.0 A g^-1 were 753, 648, 560, 490, 440, and 389 mAh g^-1, respectively. The synergetic effect of the coral-like yolk-shell structure with well-defined interconnected mesopores and highly conductive carbon resulted in the excellent Li⁺-ion storage properties of the CYS-NiO/C microspheres.

Facile synthesis of Sb2S3/MoS2 heterostructure as anode material for sodium-ion batteries

A novel Sb₂S₃/MoS₂ heterostructure in which Sb₂S₃ nanorods are coated with MoS₂ nanosheets to form a core-shell structure has been fabricated via a facile two-step hydrothermal process. The Sb₂S₃/MoS₂ heterostructure utilized as the anode of sodium-ion batteries (SIBs) shows higher capacity, superior rate capability and better cycling performance compared with individual Sb₂S₃ nanorods and MoS₂ nanosheets. Specifically, the Sb₂S₃/MoS₂ electrode shows an initial reversible capacity of 701 mAh g^-1 at a current density of 100 mA g^-1, which then remains at 80.1% of the initial performance after 100 cycles at the same current density. This outstanding electrochemical performance indicates that the Sb₂S₃/MoS₂ heterostructure is a very promising anode material for high-performance SIBs.

FeO x -Based Materials for Electrochemical Energy Storage

Iron oxides (FeO x ), such as Fe2O3 and Fe3O4 materials, have attracted much attention because of their rich abundance, low cost, and environmental friendliness. However, FeO x , which is similar to most transition metal oxides, possesses a poor rate capability and cycling life. Thus, FeO x -based materials consisting of FeO x , carbon, and metal-based materials have been widely explored. This article mainly discusses FeO x -based materials (Fe2O3 and Fe3O4) for electrochemical energy storage applications, including supercapacitors and rechargeable batteries (e.g., lithium-ion batteries and sodium-ion batteries). Furthermore, future perspectives and challenges of FeO x -based materials for electrochemical energy storage are briefly discussed.

Highly stable SnO2-Fe2O3-C hollow spheres for reversible lithium storage with extremely long cycle life

SnO₂-Fe₂O₃-C triple-shell hollow nano-spheres are fabricated by combining the template-based sol-gel coating technique and hydrothermal method, and their electrochemical performance as an anode for lithium ion batteries (LIBs) is investigated, particularly focusing on their structural stability and long term cyclability. To accomplish this, same-sized SnO₂ solid spheres, Fe₂O₃ solid spheres, SnO₂-Fe₂O₃ solid spheres, SnO₂-Fe₂O₃-C solid spheres, SnO₂ hollow spheres and SnO₂-Fe₂O₃ hollow spheres are prepared in a similar manner and their cyclic performances are compared. It is found that the as-synthesized 80 nm-sized SnO₂-Fe₂O₃-C hollow sphere electrode exhibits an extraordinary reversible capacity (1100 mA h g^-1 after 100 cycles at 200 mA g^-1) and excellent long cycle stability (475 mA h g^-1 after 1000 cycles at 2000 mA g^-1), which are attributed to the Fe-enhanced reversibility of the Li₂O reduction reaction, high electrical conductivity, high Li⁺ ion mobility, and structural stability of the carbon-coated triple-shell hollow spheres.

3D Graphene Encapsulated Hollow CoSnO3 Nanoboxes as a High Initial Coulombic Efficiency and Lithium Storage Capacity Anode

3D Graphene sheets encapsulated amorphous hollow CoSnO₃ nanoboxes (H-CoSnO₃ @reduced graphene oxide [RGO]) are successfully fabricated by first preparing 3D graphene oxides encapsulated solid CoSn(OH)₆ nanocubes, followed by an alkaline etching process and subsequent heating treatment in Ar. The hollow CoSnO₃ nanoboxes with average particle size of 230 nm are uniformly and tightly encapsulated by RGO sheets. As an anode material for Li-ion batteries, H-CoSnO₃ @RGO displays high initial Coulombic efficiency of 87.1% and large reversible capacity of 1919 mA h g^-1 after 500 cycles at the current density of 500 mA g^-1 . Moreover, excellent rate capability (1250, 1188, 1141, 1115, 1086, 952, 736, and 528 mA h g^-1 at 100, 200, 300, 400, 500, 1000, 2000, and 5000 mA g^-1 , respectively) is acquired. The reasons for excellent lithium storage properties of H-CoSnO₃ @RGO are discussed in detail.

Single step synthesized three dimensional spindle-like nanoclusters as lithium-ion battery anodes

A facile, green, mild and one-step conventional heating method was developed to synthesize monodisperse Sn-doped Fe₂O₃ nanoclusters with a novel spindle-like 3D architecture as anode materials for lithium-ion batteries.

General Strategy for Integrated SnO2/Metal Oxides as Biactive Lithium-Ion Battery Anodes with Ultralong Cycling Life

Integration of bicomponents into a greater object or assemblage is a new avenue to acquire multifunctionality for metal oxide-based anodes for lithium-ion batteries (LIBs). Herein, we report a versatile means by which precursors serve as self-sacrificing templates to form architectures of SnO₂ phase and other metal oxides. The vital challenge is the determination of appropriate synthetic system that can benefit the formation of respective precursors in a structure or single-source precursors of tin and other metal species. In the current work, by the aids of synergy action between l-proline and ethylene glycol (EG), precursors containing two metal ions are generally fabricated. Adequate flexibility of the present method has been achieved for SnO₂/M _x O _y hierarchical hybrids, including Mn₂O₃, Co₃O₄, NiO, and Zn₂SnO₄, by calcination of their corresponding SnMn, SnCo, SnNi, and SnZn precursors, respectively. When evaluated as anode materials for LIBs, the obtained SnO₂/Mn₂O₃ homogeneous hybrids, as expected, show higher specific capacity and ultralong cycling stability, gaining a reversible specific capacity of 610.3 mA h g^-1 after 600 cycles with only decay of 0.29 mA h g^-1 per cycle at 1 A g^-1 and 487 mA h g^-1 after 1001 cycles at a high current density of 2 A g^-1.

Hybrid α-Fe2O3@Ni(OH)2 nanosheet composite for high-rate-performance supercapacitor electrode

In this study, we report a facile fabrication of ultrathin two-dimensional (2D) nanosheet hybrid composite, α-Fe₂O₃ nanosheet@Ni(OH)₂ nanosheet, by a two-step hydrothermal method to achieve high specific capacitance and good stability performance at high charging/discharging rates when serving as electrode material of supercapacitors. The α-Fe₂O₃@Ni(OH)₂ hybrid electrode not only has a smooth decrease of the specific capacitance with increasing current density, compared with the sharp decline of single component of Ni(OH)₂ electrode, but also presents excellent rate capability with a specific capacitance of 356 F/g at a current density of 16 A/g and excellent cycling stability (a capacity retention of 93.3% after 500 cycles), which are superior to the performances of Ni(OH)₂ with a lower specific capacitance of 132 F/g and a lower capacity retention of 81.8% at 16 A/g. The results indicate such hybrid structure would be promising as excellent electrode material for good performances at high current densities in the future.

The application of catalyst-recovered SnO2 as an anode material for lithium secondary batteries

We studied the electrochemical characteristics of tin dioxide (SnO2) recovered from waste catalyst material which had been previously used in a polymer synthesis reaction. In order to improve the electrochemical performance of the SnO2 anode electrode, we synthesized a nanocomposite of recovered SnO2 and commercial iron oxide (Fe2O3) (weight ratio 95:5) using a solid state method. X-ray diffraction (XRD) and field emission scanning electron microscopy (FE-SEM) analyses revealed an additional iron oxide phase within a porous nanocomposite architecture. The electrochemical characterizations were based on galvanostatic charge-discharge (CD) curves, cyclic voltammetry (CV), and electrochemical impedance spectroscopy (EIS). In the first discharge, the capacity of the SnO2-Fe2O3 nanocomposite was 1700 mAh g(-1), but was reduced to about 1200 mAh g(-1) in the second discharge. Thereafter, a discharge capacity of about 1000 mAh g(-1)was maintained up to the 20th cycle. The SnO2-Fe2O3 nanocomposite showed better reversible capacities and rate capabilities than either the recovered SnO2 or commercial Fe2O3 nanoparticle samples.

Cyano-bridged coordination polymer hydrogel-derived Sn-Fe binary oxide nanohybrids with structural diversity: from 3D, 2D, to 2D/1D and enhanced lithium-storage performance

Metal oxide nanohybrids with uniform dimensions and controlled architectures possess unique compositional and structural superiorities, and thus harbor promising potential for a series of applications in energy, catalysis, and sensing systems. Herein, we propose a facile, general, and scalable cyano-bridged coordination polymer hydrogel-derived thermal-oxidation route for the construction of main-group metal and transition-metal heterometallic oxide nanohybrids with controlled constituents and architectures. The formation of Sn-Fe binary oxide nanohybrids has been demonstrated as an example by using cyano-bridged Sn(iv)-Fe(ii) bimetallic coordination polymer hydrogels (i.e., SnCl4-K4Fe(CN)6 cyanogels, Sn-Fe cyanogels) as precursors. The physicochemical properties of Sn-Fe cyanogels with different Sn/Fe ratios have been systematically examined, and it is found that perfect Sn-Fe cyanogels without unbridged Sn(iv) or Fe(ii) can be formed with Sn/Fe ratios from 2 : 1 to 1 : 2. More importantly, the simple adjustment of Sn/Fe ratios in the Sn-Fe cyanogel precursors can realize flexible dimensional control of the Sn-Fe binary oxide nanohybrids, and 2D/1D SnO2-Fe2O3 hierarchitectures, 2D SnO2-Fe2O3 nanosheets, and 3D SnO2-Fe2O3 networks have been synthesized using the Sn-Fe 1 : 2, Sn-Fe 1 : 1, and Sn-Fe 2 : 1 cyanogels as precursors, respectively. To demonstrate their compositional/structural superiorities and potential applications, the lithium-storage utilization of the Sn-Fe binary oxide nanohybrids has been selected as an objective application, and the nanohybrids exhibit Sn/Fe ratio-dependent lithium-storage performance. As a representative example, the 2D/1D SnO2-Fe2O3 hierarchitectures manifest markedly enhanced Li-storage performance in terms of reversible capacities and cycling stability in comparison with their constituent units, i.e., bare SnO2 nanosheets and Fe2O3 nanorods. The proposed cyanogel-derived thermal-oxidation strategy could open up new opportunities for constructing heterometallic oxide nanohybrids, and the rationally designed metal oxide nanohybrids may find broad applications in energy, catalysis, and sensing fields by virtue of their structural and compositional features.

Hierarchical ZnO Nanosheet-Nanorod Architectures for Fabrication of Poly(3-hexylthiophene)/ZnO Hybrid NO2 Sensor

A facile one-step solution method has been developed here to fabricate hierarchical ZnO nanosheet-nanorod architectures for compositing with poly(3-hexylthiophene) (P3HT) for fabricating a hybrid NO2 sensor. The hierarchical ZnO nanosheet-nanorod architectures were controllably synthesized by aging the solutions containing 0.05 mol·L(-1) Zn(2+) and 0.33 mol·L(-1) OH(-) at 60 °C through a metastable phase-directed mechanism. The concentration of OH(-) played a huge role on the morphology evolution. When the [OH(-)] concentration was decreased from 0.5 to 0.3 mol·L(-1), the morphology of the ZnO nanostructures changed gradually from monodispersed nanorods (NR) to nanorod assemblies (NRA), and then to nanosheet-nanorod architectures (NS-NR) and nanosheet assemblies (NSA), depending on the formation of various metastable, intermediate phases. The formation of NS-NR included the initial formation of ZnO nanosheets/γ-Zn(OH)2 mixed intermediates, followed by the dissolution of Zn(OH)2, which served as soluble zinc source. Soluble Zn(OH)2 facilitated the dislocation-driven secondary growth of ZnO nanorod arrays on the primary defect-rich nanosheet substrates. Hybrid sensors based on composite films composed of P3HT and the as-prepared ZnO nanostructures were fabricated for the detection of NO2 at room temperature. The P3HT/ZnO NS-NR bilayer film exhibited not only the highest sensitivity but also good reproducibility and selectivity to NO2 at room temperature. The enhanced sensing performance was attributed to the formation of the P3HT/ZnO heterojunction in addition to the enhanced adsorption of NO2 by NS-NR ZnO rich in oxygen-vacancy defects.

Enhanced cycle life and capacity retention of iron oxide ultrathin film coated SnO2 nanoparticles at high current densities

Optimally thick and conformal iron oxide (FeOx) ultrathin films coated on SnO₂ nanoparticles by atomic layer deposition significantly improve the cycle life and capacity retention when operated in a practical voltage window at high current densities.

Enteromorpha based porous carbons activated by zinc chloride for supercapacitors with high capacity retention

Porous carbons were prepared from enteromorpha with ZnCl₂ as active reagent. The prepared porous carbon with a specific surface area of 1651 m² g⁻¹ exhibited a specific capacitance of 206 F g⁻¹ and capacity retention of 93% even after 5000 cycles.

Fe2(MoO4)3 nanoparticle-anchored MoO3 nanowires: strong coupling via the reverse diffusion of heteroatoms and largely enhanced lithium storage properties

Fe₂(MoO₄)₃ nanoparticle-anchored MoO₃ nanowires via strong coupling via the reverse diffusion of heteroatoms and largely enhanced lithium-storage properties due to the synergistic effect of Fe₂(MoO₄)₃ nanoparticles and MoO₃ nanowires.

Cyanogel-derived formation of 3 D nanoporous SnO2-MxOy (M=Ni, Fe, Co) hybrid networks for high-performance lithium storage

Three-dimensional (3 D) nanoporous SnO2 -Mx Oy (M=Fe, Co, Ni, Cu, etc.) hybrid networks possess unique compositional and structural features that are beneficial to lithium storage and are thus anticipated to meet the performance requirements of advanced lithium-ion batteries for transportation and stationary energy storage. Herein, a facile, scalable, and versatile cyanogel-derived method for the construction of 3 D nanoporous SnO2 -Mx Oy hybrid networks was developed for the first time. The formation of 3 D nanoporous SnO2 -NiO, SnO2 -α-Fe2 O3 , and SnO2 -NiO-Co3 O4 hybrid networks was illustrated by using Sn-M cyanogels as precursors. Moreover, the anodic performance of the 3 D nanoporous SnO2 -NiO hybrid network was examined to demonstrate proof of concept. After coating with polypyrrole-derived carbon, the SnO2 -NiO@C hybrid network exhibited superior lithium-storage capabilities in terms of specific capacity, cycling stability, and rate capability.

N-doped amorphous carbon coated Fe3O4/SnO2 coaxial nanofibers as a binder-free self-supported electrode for lithium ion batteries

N-doped amorphous carbon coated Fe3O4/SnO2 coaxial nanofibers were prepared via a facile approach. The core composite nanofibers were first made by electrospinning technology, then the shells were conformally coated using the chemical bath deposition and subsequent carbonization with polydopamine as a carbon source. When applied as a binder-free self-supported anode for lithium ion batteries, the coaxial nanofibers displayed an enhanced electrochemical storage capacity and excellent rate performance. The morphology of the interwoven nanofibers was maintained even after the rate cycle test. The superior electrochemical performance originates in the structural stability of the N-doped amorphous carbon shells formed by carbonizing polydopamine.

Surfactant-assisted synthesis of Fe2O3 nanoparticles and F-doped carbon modification toward an improved Fe3O4@CFx/LiNi0.5Mn1.5O4 battery

A simple surfactant-assisted reflux method was used in this study for the synthesis of cocklebur-shaped Fe2O3 nanoparticles (NPs). With this strategy, a series of nanostructured Fe2O3 NPs with a size distribution ranging from 20 to 120 nm and a tunable surface area were readily controlled by varying reflux temperature and the type of surfactant. Surfactants such as cetyltrimethylammonium bromide (CTAB), polyvinylpyrrolidone (PVP), poly(ethylene glycol)-block-poly(propylene glycol)-block-poly(ethylene glycol) (F127) and sodium dodecyl benzenesulfonate (SDBS) were used to achieve large-scale synthesis of uniform Fe2O3 NPs with a relatively low cost. A new composite of Fe3O4@CFx was prepared by coating the primary Fe2O3 NPs with a layer of F-doped carbon (CFx) with a one-step carbonization process. The Fe3O4@CFx composite was utilized as the anode in a lithium ion battery and exhibited a high reversible capacity of 900 mAh g(-1) at a current density of 100 mA g(-1) over 100 cycles with 95% capacity retention. In addition, a new Fe3O4@CFx/LiNi(0.5)Mn(1.5)O4 battery with a high energy density of 371 Wh kg(-1) (vs cathode) was successfully assembled, and more than 300 cycles were easily completed with 66.8% capacity retention at 100 mA g(-1). Even cycled at the high temperature of 45 °C, this full cell also exhibited a relatively high capacity of 91.6 mAh g(-1) (vs cathode) at 100 mA g(-1) and retained 54.6% of its reversible capacity over 50 cycles. Introducing CFx chemicals to modify metal oxide anodes and/or any other cathode is of great interest for advanced energy storage and conversion devices.

MnO nanoparticle@mesoporous carbon composites grown on conducting substrates featuring high-performance lithium-ion battery, supercapacitor and sensor

We demonstrate a facile, two-step coating/calcination approach to grow a uniform MnO nanoparticle@mesoporous carbon (MnO@C) composite on conducting substrates, by direct coating of the Mn-oleate precursor solution without any conducting/binding reagents, and subsequent thermal calcination. The monodispersed, sub-10 nm MnO nanoparticles offer high theoretical energy storage capacities and catalytic properties, and the mesoporous carbon coating allows for enhanced electrolyte transport and charge transfer towards/from MnO surface. In addition, the direct growth and attachment of the MnO@C nanocomposite in the supporting conductive substrates provide much reduced contact resistances and efficient charge transfer. These excellent features allow the use of MnO@C nanocomposites as lithium-ion battery and supercapacitor electrodes for energy storage, with high reversible capacity at large current densities, as well as excellent cycling and mechanical stabilities. Moreover, this MnO@C nanocomposite has also demonstrated a high sensitivity for H₂O₂ detection, and also exhibited attractive potential for the tumor cell analysis.

Carbon-coated Fe-Mn-O composites as promising anode materials for lithium-ion batteries

Fe-Mn-O composite oxides with various Fe/Mn molar ratios were prepared by a simple coprecipitation method followed by calcining at 600 °C, and carbon-coated oxides were obtained by pyrolyzing pyrrole at 550 °C. The cycling and rate performance of the oxides as anode materials are greatly associated with the Fe/Mn molar ratio. The carbon-coated oxides with a molar ratio of 2:1 exhibit a stable reversible capacity of 651.8 mA h g(-1) at a current density of 100 mA g(-1) after 90 cycles, and the capacities of 567.7, 501.3, 390.7, and 203.8 mA h g(-1) at varied densities of 200, 400, 800, and 1600 mA g(-1), respectively. The electrochemical performance is superior to that of single Fe3O4 or MnO prepared under the same conditions. The enhanced performance could be ascribed to the smaller particle size of Fe-Mn-O than the individuals, the mutual segregation of heterogeneous oxides of Fe3O4 and MnO during delithiation, and heterogeneous elements of Fe and Mn during lithiation.

Enhanced lithium storage in Fe2O3-SnO2-C nanocomposite anode with a breathable structure

A novel nanocomposite architecture of a Fe2O3-SnO2-C anode, based on clusters of Fe2O3 and SnO2 nanoparticles dispersed along the conductive chains of Super P Li™ carbon black (Timcal Ltd.), is presented as a breathable structure in this paper for lithium-ion batteries. The synthesis of the nanocomposite is achieved by combining a molten salt precipitation process and a ball milling method for the first time. The crystalline structure, morphology, and electrochemical characterization of the synthesised product are investigated systematically. Electrochemical results demonstrate that the reversible capacity of the composite anode is 1110 mA h g(-1) at a current rate of 158 mA g(-1) with only 31% of initial irreversible capacity in the first cycle. A high reversible capacity of 502 mA h g(-1) (higher than the theoretical capacity of graphite, ~372 mA h g(-1)) can be obtained at a high current rate of 3950 mA g(-1). The electrochemical performance is compared favourably with those of Fe2O3-SnO2 and Fe2O3-SnO2-C composite anodes for lithium-ion batteries reported in the literature. This work reports a promising method for the design and preparation of nanocomposite electrodes for lithium-ion batteries.

CuO/Cu2O composite hollow polyhedrons fabricated from metal-organic framework templates for lithium-ion battery anodes with a long cycling life

Novel CuO/Cu2O hollow polyhedrons with porous shells were fabricated by thermal decomposition of coordination compound [Cu3(btc)2]n (btc = benzene-1,3,5-tricarboxylate) polyhedrons at 350 °C. When tested as anode materials for lithium-ion batteries, these hollow polyhedrons exhibited a reversible lithium storage capacity as high as 740 mA h g(-1) at 100 mA g(-1) after 250 cycles even if the charge-discharge process is stopped for one week during the test time.