Development Of Anode Materials Research Articles

Eco‐friendly Anode Materials for Lithium and Sodium‐ion Batteries from Wood Sources

The intricate materials found in nature boast remarkable multifunctional properties honed through millions of years of evolution, resulting in the highest optimal organization in terms of function, structure, and chemistry. Leveraging the distinctive attributes of natural materials through biomimicry present a captivating avenue for research, brimming with vast potential for groundbreaking discoveries. Among the array of precursors available, wood stands out as a prominent candidate that covered over 30% of the global land surface. Renowned for its captivating mechanical properties and anisotropic hierarchical porosity finely tuned to facilitate swift pathways, wood embodies attributes of abundance and biodegradability. Consequently, scientists have drawn inspiration from wood's exceptional characteristics to engineer batteries exhibiting remarkable electrochemical performance. For instance, the characteristic hierarchical multi‐channeled construction of wood serves as a blueprint for synthesizing energy storage materials endowed with heightened ion and electron diffusivity. Serving as an integrated carbonaceous scaffold featuring a hierarchical architecture and aligned channels, wood‐based anodes enhance ion and electron conductivities, while bolstering the kinetics of charge transfer in lithium‐ion batteries (LIBs) and sodium‐ion batteries (SIBs). This review underscores the recent strides made in utilizing wood as a hierarchically porous and renewable material for developing anode materials tailored for LIBs and SIBs.

Overview of coals as carbon anode materials for sodium-ion batteries

Abstract Energy storage is an important technology in achieving carbon neutrality goals. Compared with lithium-ion batteries, the raw materials of sodium-ion batteries are abundant, low-cost and highly safe. Furthermore, their costs are expected to be further reduced as large-scale applications take off, making them viable for energy storage applications. The primary anode material for sodium-ion batteries is hard carbon, which has a high sodium-ion storage capacity but is relatively expensive, limiting its applications in energy storage. In order to widen the applications of sodium-ion batteries in energy storage and other fields, it is particularly important to develop anode materials that have both high performance and low cost. Coals, with abundant reserves and worldwide availability, can serve as low-cost carbon sources for anode materials. Additionally, coals of different grades of metamorphism have different structural characteristics that can be tailored for the structural characteristics of coal-based anode materials for sodium-ion batteries. Recent researches on tailoring coals as the anode materials for sodium-ion batteries is summarized and the recent progress made towards mitigating the existing issues is analysed in this review. Specifically, the impacts of different grades of metamorphism on the sodium-ion storage performance of coal-based anode materials prepared with direct carbonization are discussed in detail. Studies on improving the electrochemical performances of coal-based anode materials through pore and microcrystalline structure controls, and surface as well as interface modifications are presented. Finally, the advantages and disadvantages of different preparation methods are identified. To make the industrial applications of coal-based anode materials for sodium-ion batteries more viable, the importance of the de-ashing process is introduced.

Mn-doped FeNCN as advance anode for potassium ion batteries

The development of anode materials with advanced structures to facilitate rapid charge transport and enhance potassium storage performance is urgently needed to propel the advancement of potassium ion batteries (PIBs). Transition metal carbodiimides have emerged as promising PIB electrode materials, but achieving high capacity and long-lasting cycling stability remains a challenging task. Here, Mn-doped FeNCN was synthesized by a one-step high-temperature solid-state reaction. Mn doping expands the lattice and boosts ionic conductivity, enabling favorable potassium ion storage and enhanced charging/discharging rates. In addition, density functional theory (DFT) calculations also prove that Mn-doped FeNCN facilitates the enhancement of potassium ions adsorption and promotes electron transfer. As a result, optimized Mn-FeNCN delivers high reversible capacity (402.6 mAh/g at 100 mA g−1) as PIBs anode. Even at high current density of 1000 mA g−1, it still delivers the reverse capacity of 301 mAh/g. This work provides a promising strategy to improve electrochemical performance of the transition metal carbodiimides.

Recent Progress in Developing High-Performance Anode Materials for Next-Generation Sodium-Ion Batteries

Rechargeable lithium-ion batteries (LIBs) have attracted great attention due to their large-scale energy storage applications such as electric vehicles (EVs) and grid-scale energy storage systems (ESSs). The ongoing transition towards EVs has accelerated ever-increasing demand for LIBs that causes the shortage of lithium metal resources and their expensive price. Therefore, great efforts have been made to exploit an alternative system that replaces the conventional LIBs. While sodium-ion batteries (SIBs) can be the most evident alternatives to LIBs based on the natural abundance and low cost of sodium resources, the major scientific challenges reside in developing the new anode materials due to the poor performance of conventional LIB anodes in Na cells, such as graphite and silicon. This article reviews the potential of SIBs as promising alternatives to LIBs and recent progress in developing high-performance anode materials for SIBs. The strengths and drawbacks of recently developed anode materials have been discussed, including graphite, hard carbon, silicon, phosphorus, and other transition metal compounds such as oxides, phosphides, and sulfides.

Confluence of ZnO and PTFE Binder for Enhancing Performance of Thin‐Film Lithium‐Ion Batteries

Developing anode materials with high specific capacity and cycling stability is vital for improving thin‐film lithium‐ion batteries. Thin‐film zinc oxide (ZnO) holds promise due to its high specific capacity, but it suffers from volume changes and structural stress during cycling, leading to poor battery performance. In this research, we ingeniously combined polytetrafluoroethylene (PTFE) with ZnO using a radio frequency (RF) magnetron co‐sputtering method, ensuring a strong bond in the thin‐film composite electrode. PTFE effectively reduced stress on the active material and mitigated volume change effects during Li+ ion intercalation and deintercalation. The composite thin films are thoroughly characterized using advanced techniques such as X‐ray diffraction, scanning electron microscopy, and X‐ray photoelectron spectroscopy for investigating correlations between material properties and electrochemical behaviors. Notably, the ZnO/PTFE thin‐film electrode demonstrated an impressive specific capacity of 1305 mAh g−1 (=7116 mAh cm−3) at a 0.5C rate and a remarkable capacity retention of 82% from the 1st to the 100th cycle, surpassing the bare ZnO thin film (50%). This study provides valuable insights into using binders to stabilize active materials in thin‐film batteries, enhancing battery performance.

Graphene–Encapsulated Si@C with Dual Carbon Layer Structure as High‐Performance Anode Materials for Lithium–Ion Batteries

AbstractSilicon–based materials are among the highly promising anode candidates for Li–ion batteries owing to their excellent theoretical energy density. However, the huge volume variation makes the application of silicon anode in lithium–ion batteries be full of challenge. Herein, high–performance Si@C@rGO composites anode for lithium–ion batteries are successfully prepared by graphene oxide (GO) uniformly encapsulating resorcinol–formaldehyde resin (RF) coated silicon nanoparticles. The RF‐derived carbon layer can prevent the silicon from direct contact with the electrolyte. Furthermore, the continuous conductive graphene network not only improves the overall electrical conductivity of the composite material, but also can be reversibly deformed with the volume change of silicon during the charging and discharging process, thus greatly improving the structural stability of the anode. The optimal Si@C@rGO‐2 composite provides a high specific capacity of 743.9 mAh g−−1 after 300 cycles at a current density of 1 A g−1. Meanwhile, the material also exhibits good rate performance, showing a good reversible capacity of 719.5 mAh g−1 even at a high current density of 2 A g−1. In addition, this simple and low‐cost strategy of Si@C@rGO anode can provide a design reference for the further development of anode materials in lithium–ion batteries.

Inhibition of hydrogen evolution in proton battery by sulfamic acid-caprolactam electrolyte and its electrochemical study

Proton batteries are expected to be used in large-scale energy storage systems in the future because of their reliability, safety, non-toxicity, and low cost. However, the hydrogen evolution reaction in the electrolyte of a proton battery limits the development of a high-voltage proton battery, and it is difficult to study the anode materials with lower charge and discharge potential. In this study, a novel sulfamic acid-caprolactam based electrolytes for inhibiting hydrogen evolution in the proton batteries was investigated. Aminosulfonic acid was used as a proton source in the proton batteries for the first time. In addition, caprolactam cosolvent with double hydrogen bond site was added to the electrolyte to help H3O+ de-solvent into H+, which effectively inhibited the hydrogen evolution behavior in the electrolyte of proton battery. The MoO3 electrode showed good cycling stability in the SA-H2O-CPL electrolyte. After 300 cycles, the capacity retention rate was 83.3%, and the average CE value was 99.7%. After adding caprolactam to the electrolyte, the hydrogen evolution potential is reduced to -1.7 V, and the electrochemical stability window of the electrolyte is greatly widened, which will help to develop anode materials with lower redox potential and be of great significance to the realization of high voltage proton batteries.

Fabrication of a highly active β-PbO2-Co3O4 electrode for zinc electrowinning by pulse electrodeposition: Characterization and catalytic performance analysis

High oxygen evolution overpotential and low corrosion resistance are regarded as the main drawbacks of anode materials in zinc electrowinning. To improve the electrocatalytic activity of oxygen evolution reactions (OER) and reduce energy consumption in zinc electrowinning, a Co3O4 nanoparticle-modified PbO2 anode was prepared on a Ti substrate with Sn-SbOX as an interlayer through pulse electrodeposition. The surface morphology, phase composition, and electrochemical properties of the as-prepared anode were systematically investigated. The introduction of Co3O4 nanoparticles refined the crystal size of PbO2 and increased the surface roughness of the anode. Electrochemical tests suggested the excellent electrocatalytic activity of the Co3O4 nanoparticle-modified PbO2 anode. Density functional theory (DFT) calculations revealed that Co3O4 nanoparticles reduced the OER free energy (1.58 eV) and that pulse electrodeposition reduced the PbO2 crystal size and increased the active surface area of the anode. In the simulated zinc electrowinning test, an improved current efficiency (90.6 %) was achieved, and the low energy consumption (2,508.29 kW·h) for zinc production per ton was significantly reduced as compared with that for the conventional Pb-0.75 %Ag anode. The lifetime of the modified electrode is increased by approximately 36.8 %. This provides a reference for the design and development of anode materials with high oxygen evolution activity and strong corrosion resistance in zinc electrowinning systems.

Review—Recent Advancements in Graphene-Based Electrodes for Lithium-Ion Batteries

Lithium-ion batteries (LIBs) are highly promising energy storage devices because they provide high power output and an extended cycling lifespan, resulting in a unified and efficient system. However, the current lithium-ion batteries have limitations in providing high energy density due to the slow spread of Li+ ions and the low electrical conductivity of the anode and cathode materials. This trade-off results in a situation where the power is concentrated rather than the energy. Furthermore, the significant disparities in capacity and kinetics between the anode and cathode lead to subpar rate performance and inadequate cycling stability. Hence, the development of anode materials with high power capability and structural stability holds immense importance in the context of practical LIBs. Graphene-based materials have been extensively analyzed as cathode materials in LIBs due to their distinctive structure and exceptional electrochemical characteristics. Noteworthy progress has been achieved in this field. This article summarizes recent advances in graphene-based anodes and cathodes for lithium-ion batteries. The paper concludes by analyzing current obstacles and providing recommendations for future research.

Engineering Block Copolymer-Derived Porous Carbon Nanofibers as Anodes for Sodium Ion Batteries

For decades, lithium-ion batteries have seen widespread usage in a variety of applications from consumer electronics such as smartphones to the more recent developments of electric vehicles. As the usage of lithium for batteries increases, one growing concern is the finite amount that could be found within the Earth’s crust. An alternative that is being considered is sodium-ion batteries due to how plentiful sodium is in the Earth’s crust and similar chemical properties to lithium. One of the main challenges of sodium-ion batteries is the development of anode materials because sodium does not intercalate well with graphite, which is one of the most used materials in lithium-ion batteries. One promising development for anode materials is the use of hard carbon derived from the pyrolysis of polymers such as polyacrylonitrile (PAN) which can have various morphologies and potential for doping. Our work will focus on carbon nanofibers which show high 1-dimensional transport capabilities. With the addition of a sacrificial material such as polymethylmethacrylate (PMMA) that will be removed entirely during the pyrolysis step, PAN/PMMA can be made into porous carbon nanofibers to further increase ion transport. When a PAN/PMMA blend is used, the pores are very random with a high degree of variation of pore characteristics, however studies have shown that the creation of a PAN-b-PMMA block copolymer would allow for more uniform pore structures. Our work intends to study the effects of pore structures on the electrochemical characteristics of porous carbon nanofiber anodes for sodium-ion batteries. The cycling stability data of coin cells made using hard carbon nanofibers derived from electrospun PAN (Nonporous), PAN/PMMA (Random Porous), and PAN-b-PMMA (Uniform Porous), shows their respective discharging specific capacities (mAh/g) at 0.1 A/g average at about 80, 116, and 175. A slight increase can be seen with the addition of random, nonuniform pores to the PAN hard carbon, however, with the highly uniform and controlled pores resulting from the pyrolysis of the PAN-b-PMMA block copolymer, a very significant increase in the discharging specific capacity can be seen.

Electrochemical performances and Li+-storage mechanism of highly proportional 1T-MoS2/hierarchical porous activated carbon nanocomposites

The metallic phase of molybdenum disulfide (1T-MoS2) shows distinct advantages for lithium storage owing to its superior electronic conductivity, abundance of electroactive sites, and wider interplanar spacing compared to the semiconducting phase (2H-MoS2). However, investigating lithium storage in 1T-MoS2 encounters significant challenges attributed to its thermodynamic instability during synthesis and its transformation to an amorphous structure following the irreversible conversion reaction. This study addresses these challenges by utilizing hierarchical porous activated carbon (HPAC) to achieve the highest reported proportion (85 %) of 1T-MoS2 and by restricting the potential window to induce selective intercalation reaction. Impressively, 1T-MoS2/HPAC anodes exhibit a reversible capacity that surpasses the theoretical capacity (167 mAh/g) at various current densities from 0.1 to 2.0 A/g. This superior performance extends even after 100 cycles, retaining a capacity of 276 mAh/g at 0.1 A/g. The kinetic analysis indicates that the additional capacity originated from non-Faradic lithium storage, reaching 96 % at 5.0 mV/s. Further studies employing ex-situ XRD and in-situ EIS at various lithiation depths unveil the formation of a novel permanent phase after lithiation, characterized by expanded interlayer spacing and improved conductivity compared to the un-lithiated material. These findings open promising avenues for developing anode materials for lithium-ion batteries/capacitors applications.

Dual strategies of interface engineering and core–shell structure improve potassium storage performance

Potassium-ion batteries hold practical potential for large-scale energy storage owing to their appealing cell voltage and cost-effective properties. The development of anode materials with high rate capability and satisfactory cycle lifespan, however, is one of the key factors for exploiting this electrochemical energy storage system at practical applications. Here, a bidirectional strategy is reported to obtain a double transition metal selenide CoSe2/ZnSe/C@GO core–shell heterostructure which not only promotes the diffusion of potassium ions for rapid charge transfer, but also relieves the volume expansion in long cycles to ensure the stability of the heterostructure. The results show that the presence of the heterostructure facilitates interfacial electron transport and triggers a variety of electrochemical reactions during potassiation/depotassiation, and that the core–shell structure afforded by graphene oxide stabilizes the internal heterostructure after multiple cycles. Furthermore, a K-ion capacitor is rationally constructed via core–shell heterostructure CoSe2/ZnSe/C@GO anode and commercial activated carbon cathode, the hybrid full device provides an incredibly high energy density (163.08 Wh kg−1) and high power-density (10000 W kg−1), as well as excellent cycling stability (95.6 % capacitance retention after 5200 cycles).

Pretreatment Process Before Heat Pyrolysis of Plant‐based Precursors Paving Way for Fabricating High‐Performance Hard Carbon for Sodium‐Ion Batteries

AbstractThe increasing demand for sodium‐ion batteries has risen due to sodium resources that are inexpensive and abundant compared with its counterpart of lithium‐ion batteries. Development of anode materials with high performance is central issue for sodium‐ion batteries. Plant‐based hard carbon material is a promising anode material for sodium ion batteries due to its green preparation process, favorable ions transport channel, and special porous structure. Previous studies have not systematically correlated the material's inherent structure limitation with its electrochemical properties, resulting in a complex classification and a lack selection of pretreatment methods. In this review, the intrinsic limitations in the structure of plant‐based precursors are divided into four parts, including impure components, single chemical structure, uncontrollable crystalline texture, and irregular porous structure. The previous pretreatment methods are reclassified, including purification component aiming at plant‐based precursors, optimized structure, and precabornized process aiming at intermediate products. Furthermore, the pretreatment strategies are discussed according to the preferred structures of plant‐based hard carbon and the relationship between structure and performance is systematically expounded. This review provides deep understanding of the mechanism of pretreatment and a guide for selecting appropriate pretreatment strategies to optimize the structure of plant‐based hard carbon for sodium ion batteries.

Fabrication and Study of 3D Printed ABS-Carbon Composite Anodes for Single Chamber Microbial Fuel Cells

Microbial Fuel Cells (MFCs) are electrochemical devices that exploit microbes for wastewater treatment with simultaneous power production. Concerning reactor design, electrode materials and operation modes, great achievements have been reported with an emphasis on developing anode materials to improve overall MFC performance. Anode materials (carbon cloth, carbon veil, carbon sponges) and their properties such as biocompatibility, electrical conductivity, surface area and efficient transport of waste play a very important role in power generation in MFCs. Despite their low cost, they present structural-based disadvantages eg. Fragility, and low conductivity issues. Additive manufacturing of Fused Deposition Modelling (FDM) due to its tailoring properties, has employed various polymer-based materials such as Polylactic Acid (PLA) and Acrylonitrile Butadiene Styrene (ABS) for manufacturing applications. In addition, carbon-based composites and hybrid materials eg. electrically conductive PLA and ABS have already been fabricated and are commercially available to exploit good electrical conductivity and structural rigidness. In this research, FDM was used to fabricate custom-sized electrodes made of a laboratory-produced electrically conductive ABS filament. A parametric study of conductivity and biocompatibility properties of these electrodes in correlation to 3D printer parameters was investigated and reported. Furthermore, treatment with a combination of thermal, mechanical, and chemical procedures was performed to improve the crucial parameters of anodes for MFCs.

Molecular carbon skeleton with self−regulating ion−transport channels for long−life potassium ion batteries

Developing anode materials with multiple-dimensional ion transport channels, especially to overcome huge volume expansion and sluggish ion diffusion kinetics caused by large radius of potassium ion (K+), is critical to improve the potassium storage performance. Herein, we propose a self-reversible conversion of chemical bonds with different bond lengths based on graphdiyne (GDY) to self-regulating the ion transport channels. Density functional theory (DFT) calculations and ex/in situ electrochemical tests proof the in−plane triangular−like pores (5.46 Å) of the GDY framework offer a transport channel for K+ (1.38 Å) diffusion in the direction perpendicular to the GDY plane, which differs it from carbonaceous materials whose ion diffusion is mostly governed by in−plane migration. Furthermore, the reversible alkyne−alkene bonds linking/breaking of GDY stimulated by K+ to realize self-regulating ion channels are demonstrated by in situ Raman and electro−kinetic analysis. Moreover, compared to graphite, the GDY anode with 2 orders of magnitude diffusion coefficient delivered a high reversible capacity of 202 mAh g−1 at 100 mA g−1 exhibited extraordinary durability corresponding to cycle time over 380 days. This work opens a new avenue of designing intelligent, efficient ion transport channels from molecular carbon skeleton perspective to enhance diffusion kinetic for high-performance KIBs.

Quantum dot heterostructures on N-doped graphene with accelerated diffusion kinetics for stable lithium-ion storage

The high energy density and low self-discharge rate of lithium-ion batteries make them promising for large-scale energy storage. However, the practical development of such electrochemical energy storage systems relies heavily on the development of anode materials with high multiplier capacity and stable cycle life. Here, a simple and efficient one-step hydrothermal method is used to obtain stannide heterostructures, which are loaded on N-doped graphene (SnS2/SnO2@NG) that promotes Li+ diffusion for fast charge transfer. It is demonstrated that the built-in electric field generated by the electron transfer from electron-rich SnS2 to SnO2 in the stannide heterojunction collectively provides abundant cation adsorption sites, accelerating the migration of Li+ thus improving the electrochemical reaction kinetics. Besides, the SnS2/SnO2 nanoparticles have high structural stability, and the heterojunction compressive stresses obtained from density functional theory (DFT) calculations can significantly limit the structural damage. When applied as anodes in Li+ batteries with 300 cycles at 0.5 A/g, we achieved a high reversible capacity of 892.73 mAh/g. The rational design of low-cost batteries for energy storage and conversion can benefit from the quantitative design of fast and persistent charge transfer in a stannide heterostructure.

Strategies to improve metal-organic frameworks and their derived oxides as lithium storage anode materials

Lithium-ion batteries (LIBs) are widely used as energy storage technology in emerging markets such as electric vehicles. The development of anode materials that can replace graphite materials is a hotspot of current research. Metal-organic frameworks (MOFs), as a kind of important porous inorganic organic hybrid crystals, have been developed and used as anode materials for LIBs. MOFs can be used as precursors for transition metal oxides (TMOs) with nanostructures based on unique properties such as their unique structure and morphological characteristic, and controllable skeleton composition. In this review, the application and recent progress of MOFs and their derived TMOs in anode materials for LIBs are reviewed. Attention is also paid to their electrochemical mechanisms and the mechanism of the cyclic capacity enhancement phenomenon. Finally, the challenges of MOFs and their derived TMOs as LIBs anode materials are discussed, and modification strategies to improve their electrochemical performance are analyzed and summarized.

Controllable MOF-Derived Hierarchical Hollow CoNiSe2 with Enhanced Mechanics and Kinetics for Extraordinary Rate Performance and Durable Anode of Sodium-Ion Batteries

High rates and durable anodes are the eternal pursuits of sodium ion batteries (SIBs). Constructing bimetal selenide is an efficient strategy to improve Na+ storage. Herein, a hierarchical hollow CoNiSe2/carbon compound (CoNiSe2/C) was designed as an anode of SIBs via selenizing the modified MOFs precursor. During the high-rate test, CoNiSe2/C electrodes exhibited an outstanding specific capacity of 301.9 mA h g–1 even at 20 A g–1, while an impressive cycle life over 2000 at 5 A g–1 was achieved with a residual capacity of 368.9 mA h g–1. The high-rate capability is attributed to the significantly reduced energy barrier of reaction activation and the strong microstructure of the hierarchical hollow CoNiSe2/C. It indicates that the CoNiSe2/C synthesized in this work is highly desirable and promising as a SIB anode material and sheds light on the design and development of anode materials.

Constructing bimetallic oxides with yolk structure enables high efficient anode for lithium ion batteries

Developing anode materials with high specific capacity, excellent rate performance and cycling performance is of great significance. Herein, transition metal oxides (TMOs) have been aroused much interest owing to their low cost, large theoretical capacity and chemical stability. In this work, the bimetallic oxides CoFe2O4/C composite is synthesized by solvothermal and subsequent annealing process. When used as the anode for lithium ion batteries, the CoFe2O4/C microspheres exhibit a reversible specific capacity of 1270 mAh g−1 at 100 mA g−1 after 100 cycles and about 500 mAh g−1 at a high current density of 1.0 A g−1 after 1000 cycles. These satisfactory electrochemical properties are mainly attributed to the unique yolk structure, the synergistic effect of two metal ions, carbon coating and small nanoparticles of CoFe2O4/C. This work provides an effective synthesis method for mixed TMOs with high-performance lithium storage for LIB applications.

Construction of oxygen vacancies and heterostructure in VO2-x/NC with enhanced reversible capacity, accelerated redox kinetics, and stable cycling life for sodium ion storage

Developing anode materials with high reversible capacity, fast redox kinetics, and stable cycling life for Na+ storage remains a great challenge. Herein, the VO2 nanobelts with oxygen vacancies supported on nitrogen-doped carbon nanosheets (VO2-x/NC) were developed. Benefitting from the enhanced electrical conductivity, the accelerated kinetics, the increased active sites as well as the constructed 2D heterostructure, the VO2-x/NC delivered extraordinary Na+ storage performance in half/full battery. Theoretical calculations (DFT) demonstrated that oxygen vacancies could regulate the adsorption ability for Na+, enhance electronic conductivity, as well as achieve rapid and reversible Na+ adsorption/desorption. The VO2-x/NC exhibited high Na+ storage capacity of 270 mAh g−1 at 0.2 A g−1, and impressive cyclic stability with 258 mAh g−1 after 1800 cycles at 10 A g−1. The assembled sodium-ion hybrid capacitors (SIHCs) could achieve maximum energy density/power output of 122 Wh kg−1/9985 W kg−1, ultralong cycling life with 88.4% capacity retention after 25,000 cycles at 2 A g−1, and practical applications (55 LEDs could be actuated for 10 min), promising to be utilized in a practicable Na+ storage.