Anode Material For Lithium Research Articles

Facile synthesis of Co3O4 nanocrystals with superior lithium storage properties from bis (8–hydroxyquinoline) cobalt complex as anode materials for lithium–ion batteries

A simple and facile approach to synthesis Co3O4 nanocrystals by a two–step pyrolysis process of bis (8–hydroxyquinoline) cobalt complex under Ar and air atmospheres successively. The structures and physical properties of the complex, Co@C intermediate and the Co3O4 nanocrystals are characterized by the following techniques: FTIR, XRD, TGA–DTG, Raman, FESEM, HRTEM, N2 adsorption/desorption measurement and XPS. As anode materials in lithium ion batteries, the Co3O4 nanocrystals exhibit high charge/discharge specific capacity, excellent rate performance and remarkable cycle stability. The superior electrochemical properties of the Co3O4 nanocrystals could be attributed to the nanoscaled particle size, high crystallinity and high specific surface area, which is helpful to increase the number of active sites, shorten the diffusion path of lithium ions and electrons, alleviate the volume expansion effect as well as improve the dynamic characteristics during cycling.

Rapid and Reversible Lithium Insertion with Multielectron Redox in the Wadsley-Roth Compound NaNb13O33

The development of high-performing battery materials is critical to meet the ever-increasing demand for portable energy storage for electronics and electric vehicles. Owing to their exceptionally high-rate capabilities, high volumetric capacities and long lifetimes, Wadsley-Roth compounds are promising lithium anode materials for fast-charging and high-powered devices. This study comprises an in-depth structural and initial electrochemical investigation of the Wadsley-Roth phase NaNb13O33 phase. To our knowledge, this is the first alkali-containing Wadsley-Roth compound tested for lithium insertion.Here, we report structural insights obtained from combined neutron and synchrotron diffraction as well as solid-state nuclear magnetic resonance (ss-NMR). We find that a variety of simple, solid-state methods reliably produce a ReO6-like base structure with periodic, ”shear” planes of edge-sharing NbO6 octahedra separating 5 x 3 octahedral blocks with square-planar Na+ occupying block corners. Through ss-NMR, we reveal the presence of sodium cations in block interior sites as well as square-planar block sites.Through combined experimental and computational studies, we demonstrate and rationalize the high-rate performance of this new anode material in lithium-ion half cells. Using X-ray photoelectron spectroscopy (XPS), we show the multi-electron redox of Nb, which enables capacities of 225 mA h g−1 at slow rates and anodic potentials. Without down-sizing or nano-scaling, 100 mA h g−1 of this capacity is retained at 20 C in micrometer-scale particles. By combining bond-valence mapping and DFT, we show that such excellent rate performance results from facile, multi-channel lithium diffusion down octahedral block interiors and from high electronic conductivity within shear planes. Finally, we utilize differential capacity analysis to identify optimal long-term cycling rates and achieve 80% capacity retention over 600 cycles with 30-minute charging and discharging intervals.Without optimization, these results place NaNb13O33 in the ranks of promising new high-rate lithium anode materials and warrant further research.

Urchin-like alkaline nickel–cobalt carbonate derived Ni3S4/Co3S4 nanoparticles anchored on rGO for lithium/sodium-ion batteries with enhanced capacity

Transition metal sulfides (TMS) have emerged as promising anode materials for lithium and sodium ion batteries due to their high theoretical capacity and low cost. However, the severe volume expansion during the conversion reaction causes rapid collapse inevitability when used as anode material. Herein, we pertinently fabricated nanoscale Ni3S4/Co3S4 with uniform particle size homogeneously dispersed between pleated graphene (Ni3S4/Co3S4@rGO) through facile hydrothermal assisted by cationic surfactants. The construction of 3D nanocomposites significantly shortens ion migration distances and enriches electronic pathways, accelerating charge transfer kinetics while maintaining good stability. Uniformly distributed bimetallic sulfides and rGO limit each other's aggregation, allowing the excellent structural properties of the material to be maintained over time. Thus, the Ni3S4-Co3S4@rGO electrodes deliver a high reversible capacity of 972.5 mAh/g upon 200 cycles at 100 mA g−1 in Lithium-ion battery and 487.5 mAh/g upon 150 cycles at 100 mA g−1 in Sodium-ion battery, as well as excellent rate capacity in both. These excellent properties show the potential for expansion of this simple synthetic method in the field of alkali metal batteries.

Preparation and electrochemical performance of foam–like CeO2 nanofoam as negative electrode material for rechargeable lithium–ion batteries

Oxides of transition metal oxides have been discovered as candidate anode materials for lithium–ion batteries (LIBs) owing to their extraordinary specific capacity. Moreover, to improve the electrochemical performance of energy–storage devices, the use of porous electrode materials is considered one of the most effective strategies. Herein, we report highly porous cerium oxide (CeO2) nanofoam synthesized using a facile and simple solution combustion technique (SCT). In this technique, we use two different fuels to synthesis CeO2. The prepared S–CeO2 nanofoam delivers the highest specific surface area of 142.99 m2 g−1 with a highly enhanced contact area between the electrolyte and electrode. The prepared S–CeO2–based anode offers an initial specific capacity of 1154 mAh g−1 at 100 mA g−1, which is three times higher than that of carbon–based materials. Additionally, the mesoporous S–CeO2 nanofoam exhibits good rate capability at high current densities. These attractive results suggest that S–CeO2 has great potential for use in high–performance LIB applications.

Graphite Anodes for Li-Ion Batteries: An Electron Paramagnetic Resonance Investigation.

Graphite is the most commercially successful anode material for lithium (Li)-ion batteries: its low cost, low toxicity, and high abundance make it ideally suited for use in batteries for electronic devices, electrified transportation, and grid-based storage. The physical and electrochemical properties of graphite anodes have been thoroughly characterized. However, questions remain regarding their electronic structures and whether the electrons occupy localized states on Li, delocalized states on C, or an admixture of both. In this regard, electron paramagnetic resonance (EPR) spectroscopy is an invaluable tool for characterizing the electronic states generated during electrochemical cycling as it measures the properties of the unpaired electrons in lithiated graphites. In this work, ex situ variable-temperature (10-300 K), variable-frequency (9-441 GHz) EPR was carried out to extract the g tensors and line widths and understand the effect of metallicity on the observed EPR spectra of electrochemically lithiated graphites at four different states of lithiation. We show that the increased resolution offered by EPR at high frequencies (>300 GHz) enables up to three different electron environments of axial symmetry to be observed, revealing heterogeneity within the graphite particles and the presence of hyperfine coupling to Li nuclei. Importantly, our work demonstrates the power of EPR spectroscopy to investigate the local electronic structure of graphite at different lithiation stages, paving the way for this technique as a tool for screening and investigating novel materials for use in Li-ion batteries.

Synthesis and applications of double metal MXenes: A review

MXenes are known as a new type of two-dimensional layered materials that are composed of carbide, nitride, or carbonitride of transition metals. In the recent discovery of a new class of MXenes, two transition metals occupy the metal site, called double transition metal MXenes (DTM). These multilayer composites are of interest due to their attractive features such as high ion transport, extensive surface area, and biocompatibility. Some computational methods are used to predict the properties and performance of bimetallic carbonitrides. The most important feature of this category of materials is the stability and amount of formation energy, which directly affects the choice of material in various applications. Density functional theory (DFT) calculations are very beneficial to estimate the thermodynamic stability of DTM MXenes. Of course, proper surface modification with stable terminals is needed to overcome the limitations of DTM MXenes. In this review, the electrochemical, metallic, and magnetic properties of DTM MXene have been presented first. In the following, preparation methods are summarized according to the latest published findings. Then, various applications including hydrogen evolution reactions, anode materials in lithium and sodium batteries, nanomagnetic materials, and special applications have been investigated. Finally, more challenges, prospects, and suggestions for the development of two-dimensional DTM MXenes have been presented.

Promising electrochemical performance of pristine SnO2 anodes for lithium and sodium-ion batteries

Sustainable materials with nanostructured architecture have made great strides in today’s energy storage technology. In this context, sustainable, environment-friendly SnO2 are synthesised by hydrothermal method and its electrochemical performance as anode material for lithium and sodium-ion batteries are investigated. Structural analysis such as X-ray diffraction and Raman measurement validates the formation of the tetragonal rutile structure of pristine SnO2. Scanning electron microscope image shows mixed, hollow spherical and rod- shape morphology. The Li+ and Na+ ion diffusion kinetics are conferred using cyclic voltammetry. The rate capability of pristine SnO2 anodes are tested using charge–discharge measurements. SnO2/Li half-cell shows the initial discharge capacity of 982 mAh/g at 0.1C rate and delivers the specific capacity of 219 mAh/g and 72 mAh/g at 10C and 20C rates. The SnO2/Na half-cell delivers the initial discharge capacity of 600 mAh/g and maintains the specific capacity of 110 mAh/g (1C-rate) after 500 charge–discharge cycles. The mixed spherical and rod shape morphology increases the surface area and facilitates the Li+ and Na+-ion diffusion and minimizes pulverization. Post-mortem microstructural studies are performed after 500 cycles, confirming the formation of inert oxide phases and degradation of electrolyte by-products in both LIB and SIB.

Recycling Silicon Waste from the Photovoltaic Industry to Prepare Yolk–Shell Si@void@C Anode Materials for Lithium–Ion Batteries

Silicon is considered to have significant potential for anode materials in lithium–ion batteries (LIBs) with a theoretical specific capacity of 4200 mAh g−1. However, the development of commercial applications is impacted by the volume shift that happens in silicon when charging and discharging. In this paper, a yolk–shell–structured Si@void@C anode material has been developed to address this problem. The silicon nanoparticle yolk material is obtained by recycling kerf loss (KL) Si waste from the process of slicing silicon block casts into wafers in the photovoltaic industry; the carbon shell is prepared by a hydrothermal method with glucose, and the sacrificial interlayer is Al2O3. The produced material is employed in the production of anodes, exhibiting a reversible capacity of 836 mAh g−1 at 0.1 A g−1 after 100 cycles, accompanied by a Coulomb efficiency of 71.4%. This study demonstrates an economical way of transforming KL Si waste into materials with an enhanced value for LIBs.

SiCO Ceramics as Storage Materials for Alkali Metals/Ions: Insights on Structure Moieties from Solid-State NMR and DFT Calculations.

Polymer-derived silicon oxycarbide ceramics (SiCO) have been considered as potential anode materials for lithium- and sodium-ion batteries. To understand their electrochemical storage behavior, detailed insights into structural sites present in SiCO are required. In this work, the study of local structures in SiCO ceramics containing different amounts of carbon is presented. 13 C and 29 Si solid-state MAS NMR spectroscopy combined with DFT calculations, atomistic modeling, and EPR investigations, suggest significant changes in the local structures of SiCO ceramics even by small changes in the material composition. The provided findings on SiCO structures will contribute to the research field of polymer-derived ceramics, especially to understand electrochemical storage processes of alkali metal/ions such as Na/Na+ inside such networks in the future.

Amorphous Germanium Nanomaterials as High‐Performance Anode for Lithium and Sodium‐Ion Batteries

AbstractAmorphous germanium (a‐Ge) is a promising anode material for lithium and sodium‐ion batteries (LIBs and SIBs) due to its higher capacity than traditional graphite materials. Herein, a method to prepare the a‐Ge nano‐materials with a particle size ≈10 nm is proposed by decomposing the CaGe Zintl phase at room temperature. For LIBs, a‐Ge has a high‐capacity retention of 80% even after 180 cycles (1375 mAh g−1). When employed as the anode for SIBs, two‐dimensional composites with the a‐Ge supported on the graphite nanosheets (a‐Ge@GNS) is configured, and a high reversible capacity of 526 mAh g−1 after 120 cycles is achieved. The preparation of such high‐performance amorphous Ge nanomaterials demonstrated in this work is low‐cost and environmentally‐friendly, and compared with other methods it is especially suitable for scaling‐up or mass production.

Recent Progress in SiC Nanostructures as Anode Materials for Lithium- Ion Batteries

Abstract: Large volume variation during charge/discharge of silicon (Si) nanostructures applied as the anode electrodes for high energy lithium-ion batteries (LIBs) has been considered the most critical problem, inhibiting their commercial applications. Searching for alternative high performance anodes for LIBs has been emphasized. Silicon carbide (SiC) nanomaterials, a wide bandgap semiconductor with excellent mechanical properties, have been investigated as anode electrode materials even as active materials, protective layers, or inactive buffer stuff. In this mini review, we briefly summarize the synthesis of SiC nanostructures, the application of SiC/C anode materials, and SiC/Si composite anodes in LIBs.

Investigation of the Properties of Anode Electrodes for Lithium–Ion Batteries Manufactured Using Cu, and Si-Coated Carbon Nanowall Materials

The fabrication of high-capacity, binder-free Li–ion battery anodes using a simple and efficient manufacturing process was reported in this research. The anode material for lithium–ion batteries utilized is a combination of two-dimensional (2D) carbon nanowalls (CNWs) and Cu nanoparticles (improved rate performance and capacity retention) or Si (high capacity) nanoparticles. A methane (CH4) and hydrogen (H2) gas mixture was employed to synthesize CNWs on copper foil through microwave plasma-enhanced chemical vapor deposition (PECVD). The Cu or Si nanoparticles were then deposited on the CNW surface using an RF magnetron sputtering equipment with four-inch targets. To analyze the electrochemical performance of the LIBs, CR2032 coin-type cells were fabricated using anode materials based on CNWs and other components. It was confirmed that the Cu−CNW demonstrates improved rate performance, increased specific capacity, and capacity retention compared with traditional anodes. Additionally, CNW combined with Si nanoparticles has enhanced the capacity of LIB and minimized volume changes during LIB operation.

A comparison of the electrochemical performance of graphitized coal prepared by high-temperature heating and flash Joule heating as an anode material for lithium and potassium ion batteries

Natural graphite, commonly used in energy storage applications such as the battery industry, is marked as a supply-risk material due to the elevated demand and limited resources. The synthetic graphite process is inefficient, so there is a highly required for alternative methods of making graphite as anode material. In this study, we report two efficient methods for catalytic graphitization of coal using high-temperature heating and flash Joule heating (FJH). Using both methods, the structure and morphology characterizations have demonstrated the successful structural conversion of coal from an amorphous structure into a crystalline structure. When the obtained graphitized coal samples via the high-temperature heating method (HTC) and via the FJH method (FHC) were used as anodes for lithium-ion batteries (LIBs) and potassium-ion batteries (PIBs), the HTC and FHC presented outstanding rate capability and remarkable stable cycling performance. The HTC and FHC anodes delivered initial charge capacities of 322.5 and 321.3 mAh·g−1, respectively, at a current density of 0.1C. for LIBs. When used as anodes in PIBs, the HTC and FHC delivered initial charge capacities of 265.4 and 262.2 mAh·g−1 at 0.1C current density. These results make the HTC and FHC promising materials for developing energy storage applications. Therefore, this work exploited the low price of coal and its abundant reserves, combined with the FJH technique, which is an effective method for saving energy and time, to produce high-quality graphitized coal materials, which can make this process green and economically attractive.

Development and Validation of a ReaxFF Reactive Force Field for Modeling Silicon–Carbon Composite Anode Materials in Lithium-Ion Batteries

Silicon–carbon (Si–C) nanocomposites have recently established themselves among the most promising next-generation anode materials for lithium (Li)-ion batteries. Indeed, combined Si and graphitic (sp2-C) phases exhibit high energy densities with reasonable electrochemical responses, while covalently bonded silicon carbide (SiC) compounds offer high mechanical stiffness to withstand structural degradation. However, to form and utilize a Si–C composite structure that effectively satisfies specific battery energy, power, and lifetime requirements, it is necessary to understand the underlying atomistic mechanisms at work within its individual phases and at their interfaces. Here, we develop and validate a reactive interatomic potential (ReaxFF) for the Li–Si–C system, trained and tested against a large, diverse collection of ab initio data. In conjunction with molecular dynamics and Monte Carlo simulations, our new force field links macroscale phenomena to the nanostructures of various hybrid Si–C systems in a wide range of lithiation, temperature, and stress conditions. As an illustration, it demonstrates that the high capacity of SiC (5882 mA h g–1) is caused by amorphous lithium carbides (e.g., a-Li4.4C), which soften the overall a-Li4.4(SiC)0.5 system while swelling it volumetrically up to 668%. Furthermore, our force field accurately depicts step-wise lithiation mechanisms and volume changes in Si–sp2-C composites throughout the lithiation domain of each host subsystem. It reveals the formation of a Li-rich interphase at their grain boundary, which favors their adhesion and increases the local Li (de)insertion voltage up to 1 V. These examples demonstrate the ability of the new Li–Si–C ReaxFF potential to provide atomistic-scale insights required for designing and optimizing a wide range of Si–C-based anode candidates for upcoming Li-ion battery technologies.

Preparation of Mn2SnO4 wrapped with N-doped reduced graphene oxide as a stable anode material for lithium–ion storage

Sn-based materials have been investigated as anodes for lithium-ion batteries (LIBs) due to their high theoretical capacity, low cost, and simple fabrication. Among the challenges involving these materials, volume expansion, slow kinetic reactions and poor cycling stability caused by low conductivity require further improvements in view of the exploitation of LIBs. Herein, we prepared Mn2SnO4 particles wrapped by N-doped reduced graphene (Mn2SnO4 @rGO) via a simple hydrothermal and subsequent annealing process. Moreover, composite engineering with N-doped graphene prevents volume expansion and provides a cushion from structural damage. Benefiting from this nanocomposite, the Mn2SnO4 @rGO composite electrode delivered an excellent specific capacity of 1488.5 mAh g−1 for 200 cycles at 500 mA g−1 and 712.1 mAh g−1 for 1000 cycles at 2.0 A g−1. The performance offers a simple way for fabricating binary composite materials to improve the electrochemical performance for lithium storage applications.

Unravelling Charge Storage Mechanisms of Lithium, Sodium and Potassium into Graphene‐Coffee Waste Derived Hard Carbon Composites

AbstractHard carbons are promising anode materials for lithium, sodium and potassium‐ion batteries attending to their low cost, simple processing technology and outstanding electrochemical performance. However, their complex structure and controversial carrier‐ion storage mechanisms makes difficult the prediction of their performance. Herein, we investigate the insertion storage mechanisms behind of three different alkali metal ions (lithium, sodium and potassium) into a hard carbon composite obtained by the pyrolysis of coffee waste and graphene oxide. The insertion/deinsertion processes have been monitored by galvanostatic intermittent titration technique and operando X‐Ray diffraction. Results reveal that alkaline metal ions follow an adsorption‐intercalation mechanism where the high potential region can be ascribed to the adsorption of the alkaline metal ions on the surface active sites, while slopping region arises from their intercalation between the pseudo‐graphitic micro‐crystallites. Moreover, the graphene‐coffee waste hard carbon exhibits a notorious capacity retention after 300 charge/discharge cycles in all the alkaline metals evaluated.

Three-dimensional architecture of multichannel carbon fibers for enhanced lithium and sodium storage properties

Transition metal sulfides have garnered considerable attention in recent times as promising anode materials due to their high theoretical capacities for lithium and sodium storage. However, pristine metal sulfides suffer from poor rate and cycling stability. Herein, Se substituted NiS2 (denoted as NiSexS2-x) nanoparticles decorated multichannel carbon fibers (MCF/NiSexS2-x) were fabricated as anode materials for lithium and sodium-ion batteries. The distinct composition and unique architecture endow MCF/NiSexS2-x with enhanced reaction kinetics, improved electric conductivity, and superior structural stability. Consequently, the MCF/NiSexS2-x anode delivered a high capacity of >475 mAh g−1 at 1 A g−1 for Li storage with a highly stable cycle life of over 300 cycles. Moreover, when applied in sodium-ion batteries, MCF/NiSexS2-x achieved a superior capacity of >456 mAh g−1 at 0.2 A g−1 over 100 cycles with good rate retention.

Synthesis, structure investigation and future prospects of transition metal oxides/carbon cloth hybrids as flexible binder-free anode materials for lithium- ion batteries

• Binder-free hybrid electrode materials were formed by non-stationary electrolysis. • Main phases (Mo 4 O 11 , MoO 3 MoO 2 , Mo 8 O 23 , Mo 9 O 26 , WO 2 , MnO 2 ) were confirmed by TEM. • The binder-free hybrid electrode materials exhibited high charge/discharge capacity. Transition Metal Oxides/Carbon Cloth Hybrids were synthesized by electrochemical method using non-stationary electrolysis. The morphology and surface structure of the developed hybrids were studied using scanning electron microscopy and transmission electron microscopy. According to X-ray spectral microanalysis, the main elements of hybrid oxide coatings are Mo, Co, Fe, Mn, W. The charge state of elements in the surface layer of a hybrid oxide coating was studied by X-ray photoelectron spectroscopy and it was found that oxygen is sufficient for the oxidation of metals to higher oxides. Molybdenum is oxidized mainly to the state of +6, iron to +2 and +3, manganese is not lower than +3. The calculation of electronograms showed that the most probable phases of the obtained material are a mixture of molybdenum oxides Mo 4 O 11 , MoO 3 , MoO 2 , Mo 8 O 23 , Mo 9 O 26 , tungsten and manganese dioxide WO 2 and MnO 2 , respectively.

Exploring the effect of layer spacing of graphene for lithium single-atom diffusion using first principles calculations

Bilayer graphene is a representative two-dimensional carbon material and a promising anode material for lithium batteries.The layer spacing variation of bilayer graphene can affect the diffusion of lithium atoms, and thus affect the rate performance of lithium battery anode materials.To reveal the mechanism of the diffusion of the lithium atom in bilayer graphene at different layer spacing, the lowest energy configuration,formation energy, diffusion energy barrier, differential charge density and Mulliken population are calculated and investigated according to the first principles of density functional theory (DFT). The calculation results show that a single lithium atom is preferentially deposited at the hollow site of graphene, and the lithium atom embedded graphene gradually changes from A-B stacking mode (shifted graphene) to A-A stacking mode (aligned graphene) with the increase of layer spacing. For both A-A and A-B stacking mode bilayer graphene, the increase of layer spacing improves the formation energy of the system and reduces the stability of the structure. The increase of the layer spacing also improves the diffusion energy barrier of A-B stacking graphene and decreases that of A-A stacking. This means that the increase of layer spacing can make the diffusion of the lithium atom harder in A-B stacking while easier in A-A stacking. The results of differential charge density and Mulliken population verifiedthatwhen the layer spacing increases to 1.8 nm, the effect of bilayer graphene on the lithium atom is similar than that of monolayer graphene. The calculation results of OCV and the maximum capacity prove the potential of bilayer graphene as anode material. The results provide a new understanding of the lithium atom diffuse in bilayer graphene, and the diffusion properties of the lithium atom can be optimized by adjusting the layer spacing appropriately.

High-Performance Lithium-Ion Storage of FeTiO3 with Morphology Adjustment and Niobium Doping.

Ferrous titanate (FeTiO3) has a high theoretical capacity and physical and chemical properties stability, so it is a potential lithium anode material. In this study, FeTiO3 nanopowder and nanosheets were prepared by the sol–gel method and the hydrothermal method. In addition, niobium-ion doping was carried out, the radius of Nb close to Ti so the Nb can easily enter into the FeTiO3 lattice. Nb can provide more free electrons to improve the electrochemical performance. Then, the effects of the morphology and niobium doping on the microstructure and electrochemical properties of FeTiO3 were systematically studied. The results show that FeTiO3 nanosheets have a better lithium storage performance than nanopowders because of its high specific surface area. A certain amount of niobium doping can improve the electrochemical performance of FeTiO3. Finally, a 1 mol% niobium-doping FeTiO3 nanosheets (1Nb-FTO-S) electrode provided a higher specific capacity of 782.1 mAh g−1 at 50 mA g−1. After 200 cycles, the specific capacity of the 1Nb-FTO-S electrode remained at 509.6 mAh g−1. It is revealed that an increased specific surface area and ion doping are effective means to change the performance of lithium, and the proposed method looks promising for the design of other inorganic oxide electrode materials.