High-performance Anode For Sodium-ion Batteries Research Articles

Pb nanospheres encapsulated in metal–organic frameworks-derived porous carbon as anode for high-performance sodium-ion batteries

Alloying-type anode materials are considered promising candidates for sodium-ion batteries (SIBs) due to their high theoretical capacities. However, their application is limited by the severe capacity decay stemming from dramatic volume changes during Na+ insertion/extraction processes. Here, Pb nanospheres encapsulated in a carbon skeleton (Pb@C) were successfully synthesized via a facile metal–organic frameworks (MOFs)-derived method and used as anodes for SIBs. The nanosized Pb particles are uniformly incorporated into the porous carbon framework, effectively mitigating volume changes and enhancing Na+ ion transport during discharging/charging. Benefiting from this unique architecture, a reversible capacity of 334.2 mAh g−1 at 2 A g−1 is achieved after 6000 cycles corresponding to an impressive 88.2 % capacity retention and a minimal capacity loss of 0.00748 % per cycle. Furthermore, a high-performance full sodium-ion battery of Pb@C//NVPF was constructed, demonstrating a high energy density of 291 Wh kg−1 and power density of 175 W kg−1. This facile MOFs-derived method offers insights into the design of high-capacity alloy-type anode materials using Pb sources, opening up new possibilities for innovative approaches to Pb recycling and pollution prevention.

Carbon nanotube reinforced FeMoO4 nanorods as a high-performance anode for sodium-ion batteries

Iron molybdate (FeMoO4) nanostructures show great promise as a superior anode for sodium-ion batteries. However, its use in practical application is hampered by its poor electronic conductivity, large volume changes and sluggish reaction kinetics. Herein, we have developed an interconnected network of multiwall carbon nanotube (CNT) and FeMoO4 (FMO) by a simple one-step hydrothermal method. As well as providing efficient channels for charge transfer and diffusion, highly conductive CNTs also have a degree of volume elasticity and excellent electrical conductivity to ensure migration of sodium ions, enabling both fast kinetics and long-term stability. As a result, the FMO@CNT anode delivers a high reversible capacity of 485 mA h g−1 at 0.05 A/g and very long cycling stability with a capacity of 75 mA h g−1 after 1000 cycles at 1 A/g. Furthermore, by combining the ex-situ X-ray diffraction, ex situ X-ray photoelectron spectroscopy and cyclic voltammetry results, sodium ion storage mechanism of the FMO@CNT electrode obeys a conversion mechanism. The results of this work provide a better understanding on the sodium ion storage mechanism of binary metal oxides.

Vanadium nitride induced method to construct cobalt sulfides homologous heterojunction toward ultrafast and high-capacity sodium-ion storage

In recent years, heterojunction has attracted widespread attention as an anode for sodium-ion batteries since they can effectively optimize the materials’ rate performance and cycling stability. However, the advantage is choked by multi-element composition and stepwise synthesis process. Herein, cobalt sulfide (Co9S8/CoS) homologous heterojunction deposited at vanadium nitride/carbon nanofibers is synthesized as an excellent anode for high-performance sodium-ion batteries in one step by employing the “3d-orbital electron complementary effect” combined with high-temperature heat-treatment technology. The Co9S8/CoS homologous heterojunction successfully overcomes the inherent drawback of Co9S8 and possesses an ultrafast charging/discharging process, outstanding reversible specific capacity, and remarkable rate capability. A systematic study reveals that vanadium nitride is a key trigger for forming Co9S8/CoS heterojunction. When used as anode materials for sodium-ion batteries, it reaches a high specific capacity of 353.0 mAh/g at a current density of 10 A/g (615.8 mAh/g at a current density of 0.05 A/g) due to the presence of heterointerface. Theoretical calculations show that the construction of the heterostructure enhances the sodium-ion storage capacity and storage kinetics compared with pristine Co9S8. This discovery opens an interesting strategy for constructing homogeneous heterojunctions and broadens the horizons for designing energy storage and conversion materials.

Exploring Carbonization Temperature to Create Closed Pores for Hard Carbon as High-Performance Sodium-Ion Battery Anodes.

Biomass-derived porous carbon materials are meaningful to employ as a hard carbon precursor for anode materials of sodium-ion batteries (SIBs) from a sustainability perspective. Here, a straightforward approach is proposed to develop rich closed pores in pinenut-derived carbon, with the aim of improving Na+ plateau storage by adjusting the pyrolysis temperature. The optimized sample, namely the pinenut-derived carbon at 1300 °C, demonstrates remarkable reversible specific capacity of 278 mAh g-1, along with a high initial Coulomb efficiency of 85% and robust cycling stability (with a capacity retention of 89% after 800 cycles at 0.2 A g-1). In situ and ex situ analyses unveil that the developed closed pores play a significant role in enhancing the plateau capacity, providing compelling evidence for the "adsorption-filling" mechanism. Moreover, the corresponding full-cell achieves a high energy density of 245.7Wh kg-1 (based on the total weight of both electrode active materials) and exhibits outstanding rate capability (191.4 mAh g-1 at 3 A g-1).

A surface-induced assembly strategy to fabricate flexible carbon nanofiber/coal-based carbon dots films as free-standing anodes for high-performance sodium-ion batteries

Flexible electrodes with superior stability, high performance, and low cost have drawn numerous considerations in energy storage devices. Here, we developed a facile and robust strategy to prepare coal-based carbon dots (i.e., CDs) with high yields derived from lignite by microwave-assisted mild oxidation and further fabricate a carbon nanofiber film decorated with CDs (i.e., CNF@CDs) by electrospinning water-soluble CDs with polyacrylonitrile (i.e., PAN) through thermal treatment and carbonization and applied as flexible electrodes for sodium-ion batteries. The as-prepared CNF@CDs as binder-free anode presents a reversible capacity of 223 mAh g−1 at 20 mA g−1 and obtains a high capacity retention of 96% over 400 cycles. The outstanding electrochemical properties were attributed to the unique structure of CNF@CDs with the optimal ratio of carbon nanofiber and coal-based carbon dots, in which carbon fiber with the 3D framework facilitates the speed of ion diffusion and electron transport as well as the surface-induced assembly of CDs on the surface of the PAN fibers brings in strong structure stability and electrode integrity. The current study supplies a novel and effective approach to constructing flexible electrodes with superior stability and high performances from low-cost materials, which has potential application prospects in flexible energy storage devices.

One-step in-situ synthesis of bimetallic-doped disordered carbons as anode for high-performance sodium-ion batteries

Since sodium-ion batteries are considered to be the promising energy storage devices, carbon materials as the anodes have been intensively studied. They have good cycling stability, but their capacities are generally not high enough to meet the increasing demands. In order to solve this problem, a carbon-bimetallic composite is synthesized in one step using a simple pyrolysis method with low-cost biomass and cobalt ferrate as the precursors. This simple synthesis method allows the in-situ production of bi-alloys embedded into disordered carbon matrix derived from the tapioca starch to form high-performance anode material for sodium-ion batteries. The initial discharge capacity is 712 mA h g−1 at 0.05 A g−1and the initial Coulombic efficiency is 89.2%. Moreover, the introduction of bi-alloys not only facilitates the reaction kinetics, but also effectively mitigates the volume expansion and consequently promotes the cyclability. As a result, the half-cell sodium-ion battery delivers a capacity of more than 419 mA h g−1 at a high current of 10 A g−1, and after 200 cycles at a current density of 1 A g−1, its capacity degradation is only 0.2% per cycle with a Coulombic efficiency of about 100%. This high-performance materials with a low-cost preparation method could be great potential for commercialized applications.

CoS2@C nanospheres encapsulated in N-doped graphene oxide as high-performance anode for sodium-ion battery

CoS2@C nanospheres encapsulated in N-doped graphene oxide as high-performance anode for sodium-ion battery

Hollow spheres constructed by ZnS-CoS2 @N-doped carbon@N-doped carbon as anodes for high-performance sodium-ion batteries

Hollow spheres constructed by ZnS-CoS2 @N-doped Carbon@N-doped carbon (ZnS-CoS2 @NC@NC) are successfully synthesized using template method combined with NC coating procedure. For SIBs anode, ZnS-CoS2 @NC@NC electrode exhibits excellent rate property and sustainable capacity of 164 mAh g−1 at 5 A g−1 after 1000 cycles. The superior sodium storage performance for ZnS-CoS2 @NC@NC composites is benefited from its distinctive structure, in which the hollow architecture for ZnS/CoS2 @NC@NC composites can buffer the volume change of ZnS/CoS2 and enhance electronic/ionic conductivity within charge/discharge processes. Furthermore, the NC shell layer can further alleviate structural degradation of ZnS/CoS2 @NC@NC hollow spheres, and supply more effective active sites.

Highly Stable ZnS Anodes for Sodium-Ion Batteries Enabled by Structure and Electrolyte Engineering.

Zinc sulfide is a promising high-capacity anode for practical sodium-ion batteries, considering its high capacity and the low cost of zinc and sulfur sources. However, the pulverization of particulate zinc sulfide causes active mass collapse and penetration-induced short circuits of batteries. Herein, a zinc sulfide encapsulated in a nitrogen-doped carbon shell (ZnS@NC) was developed for high-performance anodes. The confinement effect of nitrogen-doped carbon stabilizes the active mass structure during cycling thanks to the robust chemically and electronically bonded connections between nitrogen-doped carbon and zinc sulfide nanoparticles. Furthermore, the cycling stability of the ZnS@NC anode is boosted by the robust inorganic-rich solid electrolyte interphase (SEI) formed in cyclic and linear ether-based electrolytes. The ZnS@NC anode displayed a reversible specific capacity of 584 mAh g-1, an excellent rate capability of 327 mAh g-1 at 70 A g-1, and a highly stable cycling performance over 10000 cycles. This work provides a practical and promising approach to designing stable conversion anodes for high-performance sodium-ion batteries.

Hierarchically porous closed-pore hard carbon as a plateau-dominated high-performance anode for sodium-ion batteries.

Micro-spherical hard carbons (MSHCs) with distinct porosity features have been synthesized from an easy microwave-assisted solvothermal pre-treatment of sucrose, followed by carbonization, as anodes for sodium-ion batteries. The MSHC exhibits large interlayer spacing of turbostratic graphene nanosheets with more defective graphene planes, hierarchical pore structures, and closed pores. The MSHC anode delivered a high reversible capacity of 422 mA h g-1 at 0.1C rate with a low-potential battery-like plateau contribution of 57%, which is the best reported reversible sodium storage performance to date for an unmodified HC for SIBs. The MSHC shows 251 and 140 mA h g-1 high-rate capacities at 1C and 5C, respectively, with excellent capacity retention of 84% after 500 cycles at 1C. GITT and EPR measurements confirm the storage mechanism shift from intercalation to the quasi-metallic sodium clusters in the closed pores at low potentials. The full cell with the MSHC anode and a P2-Na0.67Ni0.33Mn0.67O2 (NNMO) cathode delivered a high energy density of 292 W h kg-1 at a working potential of 3.2 V.

Electrochemical evaluation of Sn/C composites as high-performance anodes for sodium-ion batteries

Electrochemical evaluation of Sn/C composites as high-performance anodes for sodium-ion batteries

BeN4 nanoribbon-based 3D porous metallic and ductile monolith for high-performance sodium-ion battery anode

3D BeN4-nanoribbon-based porous and metallic structure is promising for sodium-ion battery anode.

Nanoconfinement of ultra-small Bi2Te3 nanocrystals on reduced graphene oxide: a pathway to high-performance sodium-ion battery anodes.

Bismuth telluride (Bi2Te3) nanomaterials have attracted considerable attention owing to their intriguing physicochemical properties and wide-ranging potential applications arising from their distinctive layered structure and nanoscale size effects. However, synthesizing sub-100 nm ultra-small Bi2Te3 nanocrystals remains a formidable challenge. To date, there has been little investigation on the performance of these ultra-small Bi2Te3 nanocrystals in sodium-ion batteries (SIBs). This study presents a general strategy for synthesizing ultra-small Bi2Te3 nanocrystals on reduced graphene oxide (Bi2Te3/rGO) through a nanoconfinement approach. First-principles calculations and electrochemical kinetic studies confirm that the ultra-small Bi2Te3/rGO composite material can effectively mitigate volumetric expansion, preserve electrode integrity, and enhance electron transfer, Na-ion adsorption, and diffusion capacity. As a result, the Bi2Te3/rGO electrode demonstrates a remarkable initial specific capacity of 521 mA h g-1 at 0.1 A g-1, showcasing outstanding rate behaviour and long-lasting cycle life exceeding 800 cycles at 1 A g-1 while preserving exceptional rate properties. The function of the battery is indicated by ex situ TEM and XPS findings, which propose a conventional dual mechanism involving conversion and alloying. This work paves the way for rapid advancements in Bi2Te3-based SIB anodes while contributing to our understanding of sodium ion storage mechanisms.

Fabrication of Hollow and Hierarchical CuO Micro-Nano Cubes Wrapped by Reduced Graphene Oxide as a Prospective Anode for SIBs.

In this study, hollow and hierarchical CuO micro-nano cubes wrapped by reduced graphene oxide (H-CuO MNCs@rGO) were designed and successfully fabricated via a novel three-step wet-chemical method. Benefiting from its unique hollow and hierarchical micro-nano structures, H-CuO MNCs@rGO exhibited significantly enhanced electrochemical Na+ storage performance when utilized as anode material for sodium-ion batteries (SIBs). Specifically, H-CuO MNCs@rGO demonstrated a specific capacity of 380.9 mAh g-1 in the initial reversible cycle and a capacity retention of 218.9 mAh g-1 after 150 cycles at a current density of 300 mA g-1. Furthermore, through the dominant pseudocapacitive behavior, an optimized rate capability of 221.2 mAh g-1 at 800 mA g-1 can be obtained for H-CuO MNCs@rGO. The comprehensive Na+ storage properties of H-CuO MNCs@rGO obviously exceeded those of hollow CuO cubes (H-CuO MNCs) and bulk CuO anodes. Such enhanced Na+ storage performances of H-CuO MNCs@rGO can be attributed to its reasonable hollow and hierarchical micro-nano structures, which provide abundant redox active sites, shorten Na+ migration pathway, buffer volume expansion, and improve electronic/ionic conductivity during sodiation/desodiation process. Our strategy provides a facile and innovative approach for the design of CuO with rational micro-nano structure as a high-performance anode for SIBs, which would also be a guiding way for tailoring transition metal oxides in other scalable and functional applications.

Dual carbon confined MoS2 hierarchical microspheres as high-performance anode for sodium-ion batteries with superior cycling stability

Due to the growing demand in the energy market, sodium-ion batteries (SIBs) have garnered significant attention as potential energy storage devices for large-scale applications. However, the sluggish kinetics and significant volume expansion during cycling bring about the poor electrochemical behavior of SIBs. In this work, a dual carbon including internal hard carbon core and external N-doped carbon shell confined MoS2 hierarchical microspheres (HC@MoS2@NC) nanocomposites are prepared as anode for SIBs with superior cycling stability and good rate capability. The dual carbon confinement can improve the structural stability of MoS2. The dual carbon with good electronic conductivity ensures well battery rate capability of MoS2 anode. Meanwhile, the larger interlayer spacing of 10.09 Å caused by NC insertion make MoS2 store more Na+. As a consequence, the HC@MoS2@NC nanocomposite delivers a high capacity of 321 mAh g−1 at 0.1 A g−1 after 100 cycles. At large current density of 2 A g−1, a high capacity of 180 mAh g−1 can still be achieved after 1000 cycles. Even at larger current density of 5 A g−1, the capacity can still be kept at 162 mAh g−1 after 100 cycles.

Electrochemical evaluation of Sn/C composites as high-performance anodes for sodium-ion batteries

Electrochemical evaluation of Sn/C composites as high-performance anodes for sodium-ion batteries

Flash-pyrolyzed coal char as a high-performance anode for sodium-ion batteries

This work explores a novel approach for improving the sodium-ion battery performance of coal char using flash pyrolysis and an ether-based electrolyte. Coal char is an ultra-low cost hard carbon with promising application as an anode material in sodium-ion batteries. During flash pyrolysis, char is heated at 1000 °C/s in a drop-tube furnace to create a highly-irregular structure. The larger d-spacing and smaller closed micropore diameter of flash-pyrolyzed char increases anode capacity compared to traditional slow-pyrolyzed char electrodes. The sodium-ion battery anode performance of flash-pyrolyzed char is further improved using an ether-based electrolyte in place of the traditional ester-based electrolyte. Performance improvements include greater initial Coulombic efficiency (58% in ester- vs. 64% in ether-based electrolyte) and improved specific capacity in an ether-based electrolyte. Overall, the combination of flash pyrolysis and ether-based electrolyte increases the sodium-ion battery discharge capacity of coal char by over 50%, from 72.5 mAh g−1 (slow-pyrolyzed char in ester-based electrolyte) to 109.4 mAh g−1 (flash-pyrolyzed char in ether-based electrolyte) (50 mA g−1 discharge rate). The results highlight improvements that can be realized through flash pyrolysis of coal char for battery applications and the numerous processing advantages of flash vs. slow pyrolysis.

Electrochemical properties of bismuth chalcogenide/MXene/CNT heterostructures for application in Na-ion batteries

The development of high-performance anodes for sodium-ion batteries (SIBs) has recently attracted great attention. Most of the proposed anode materials for SIB systems suffer from insufficient electrical and mechanical contact of the active material with the current collector causing low reversible capacity and short lifespan. To solve this issue, an innovative approach could be the direct synthesis of the active material around and on the top of an electrically conductive network. The nanostructuring with SWCNTs and MXenes increases the active surface area, improves expansion/contraction properties, and establishes a direct mechanical and electrical contact. In this work the performance of binder-free Bi2Se3/SWCNT and Bi2Se3/MXene/SWCNT anode materials, which were synthesized by the direct physical vapor deposition of Bi2Se3 nanostructures on SWCNT and MXene/SWCNT network systems, was investigated. The results showed that the Bi2Se3/SWCNT electrode with the mass ratio of (1:1) exhibits excellent rate performance and high discharge capacity in the short-term (0.1 A g−1) and long-term (5.0 A g−1) cycling by delivering 247 and 120 mAh g−1 respectively demonstrating its perspectives for the application as an anode in SIBs.

ZnS/CoS@C Derived from ZIF-8/67 Rhombohedral Dodecahedron Dispersed on Graphene as High-Performance Anode for Sodium-Ion Batteries.

Metal sulfides are highly promising anode materials for sodium-ion batteries due to their high theoretical capacity and ease of designing morphology and structure. In this study, a metal-organic framework (ZIF-8/67 dodecahedron) was used as a precursor due to its large specific surface area, adjustable pore structure, morphology, composition, and multiple active sites in electrochemical reactions. The ZIF-8/67/GO was synthesized using a water bath method by introducing graphene; the dispersibility of ZIF-8/67 was improved, the conductivity increased, and the volume expansion phenomenon that occurs during the electrochemical deintercalation of sodium was prevented. Furthermore, vulcanization was carried out to obtain ZnS/CoS@C/rGO composite materials, which were tested for their electrochemical properties. The results showed that the ZnS/CoS@C/rGO composite was successfully synthesized, with dodecahedrons dispersed in large graphene layers. It maintained a capacity of 414.8 mAh g-1 after cycling at a current density of 200 mA g-1 for 70 times, exhibiting stable rate performance with a reversible capacity of 308.0 mAh g-1 at a high current of 2 A g-1. The excellent rate performance of the composite is attributed to its partial pseudocapacitive contribution. The calculation of the diffusion coefficient of Na+ indicates that the rapid sodium ion migration rate of this composite material is also one of the reasons for its excellent performance. This study highlights the broad application prospects of metal-organic framework-derived metal sulfides as anode materials for sodium-ion batteries.

Carbon encapsulated FeS nanosheet-nanoribbon interwoven sandwich structure as efficient sodium-ion battery anodes

Carbon encapsulation and optimization of nanoparticle structure are key strategies in the development of battery electrode materials. Herein, we report a simple, one step chemical vapor deposition-like method to synthesize carbon encapsulated sandwich structured nanosheets/nanoribbons of ferrous sulphide (FeS@C NSRs) as a high performance sodium-ion battery anode material. The structurally advantageous FeS@C NSRs arises from heating Fe foam in the presence of a sulphur-containing resin, which supplies both the sulphur and carbon for the reaction. FeS@C NSRs maintains a high capacity of 582.8 mAh g−1 at 0.1 A g−1 for 120 cycles and a high rate capability of 270 mAh g−1 at 10 A g−1 for 2500 cycles. The impressive cycling performance results from fast electron and ion transfer with low structural strain on the bulk material. Furthermore, in situ Raman spectroscopy and XRD also reveal evidence that FeS@C NSRs cycles via a fully reversible conversion reaction pathway facilitated by the C–S–Fe bond. The efficient synthesis method could also be explored to produce other carbon coated transition metal sulphides for electrochemical applications.