Anode For Sodium-ion Batteries Research Articles

An Oriented Diffusion Strategy to Configure All-Region Ultrahigh-Density Metal Single Atoms for High-Capacity Sodium Storage.

Single-atom metals (SAMs), despite being promising for high-utilization catalysis, biomedicine, and energy storage, usually suffer from limited catalytic performance caused by low metal loading. Herein, via an oriented diffusion strategy, all-region ultrahigh-loading (18.9wt.%) Sn-SAMs over carbon nanorings matrix (Sn-SAMs@CNR) are initially achieved based on the transformation of a g-C3N4@SnO2@polydopamine ring-like nested structure. The formation process of Sn-SAMs involves a critical conversion from oxygen-coordination (SnO2) to nitrogen-coordination (Sn-N4) and simultaneous anti-Osterwalder ripening promoted under spatial confinement. Notably, the g-C3N4-derived N-containing gaseous intermediates dynamically drive the oriented diffusion (inside-out diffusion) of Sn-SAMs across the carbon nanorings, realizing an all-region ultrahigh loading of SAMs throughout the carbon matrix. This strategy is also applied to other metal materials (Fe, Co, Ni, Cu, and Sb), and features excellent universality. When applied as the anode for sodium-ion batteries, experimental analyses and theoretical calculations demonstrate that high-loading Sn-N4 active sites significantly optimize electron density distribution and improve reaction kinetics. Consequently, Sn-SAMs@CNR exhibits outstanding durability of 364mAhg-1 even after 5000 cycles with an impressively low (0.00068%) capacity decay per cycle. This work opens up a universally new avenue for all-region ultrahigh loading of SAMs to carbon matrix for high-performance energy storage.

Towards More Sustainable Schiff Base Carboxylate Anodes for Sodium-Ion Batteries

Bismine sodium salt (BSNa), a Schiff base with two sodium carboxylates, has shown promising electrochemical performance as an anode material. However, its synthesis involves toxic reagents and generates impurities, requiring significant solvent use for purification. This study introduces a novel synthetic method using sodium hydroxide as the sole reagent, which acts as both a base and Na source in the ion exchange step. With this procedure, we reduce the amounts of chemicals, diminish toxicity, improve the purity of the target compound, and use less solvent while maintaining comparable electrochemical performance. Additionally, the procedure is carried out under anhydrous conditions that avoid the undesirable hydrolysis of the imine linkages. In a previous report, the processing of the composite electrode was not established. In this article, we address this issue; the electrochemical performance, specifically the rate capability, is enhanced by processing the electrodes in laminate form rather than powder. As alternative to N-methyl-2-pyrrolidone (NMP), a common but disadvantageous solvent in laminate processing, other solvents were explored by testing acetone (DMK), methylisopropylketone (MIPK), and a DMK-NMP mixture. The remarkable electrochemical performance (specific capacity of 260–280 mAh/g, and capacity retentions higher than 84% at 1C (260 mA/g) remained consistent across these solvents. Furthermore, we investigated replacing copper with aluminum as the current collector to reduce costs and increase the energy density of the battery. While aluminum performed comparably to copper at low specific currents C/10 (26 mA/g), it showed a significant shift in the redox process potentials at higher specific currents.

High-Capacity Anode for Sodium-Ion Batteries Using Hard Carbons Derived from Polyurea-Cross-Linked Silica Xerogel Powders

High-Capacity Anode for Sodium-Ion Batteries Using Hard Carbons Derived from Polyurea-Cross-Linked Silica Xerogel Powders

Three-Dimensional Flexible SnO2@Hard Carbon@MoS2@Soft Carbon Fiber Film Anode toward Ultrafast and Stable Sodium Storage.

Developing flexible electrodes for the application in sodium-ion batteries (SIBs) has received great attention and has been still challenging due to their merits of additive-free, lightweight, and high energy density. In this work, a free-standing 3D flexible SIB anode with the composition of SnO2@hard carbon@MoS2@soft carbon is designed and successfully synthesized. This electrode combines the energy storage advantages and hybrid sodium storage mechanisms of each material, manifested in the enhanced flexibility, specific capacity, conductivity, rate, cycling performances, etc. Based on the synergistic effects, it exhibits much higher specific capacity than SnO2 carbon nanofibers, as well as more excellent cycling performance (250 mA h g-1 after 500 cycles at 1 A g-1) than MoS2 nanospheres (32 mA h g-1). In addition, relevant kinetic mechanisms are also expounded with the aid of theoretical calculation. This work provides a feasible and advantageous strategy for constructing high-performance and flexible energy storage electrodes based on hybrid mechanisms and synergistic effects.

Synergistic effect of holey graphene and CoSe2-NiSe2 heterostructure to enhance fast Na-ion transport

Inspired by the “Barrel principle” and based on the working principle of the “rocking chair”. We propose two shortboards that “bulk diffusion rate” and “ion reaction rate”, which affect the fast charging of sodium ion batteries (SIBs). The holey reduced graphene oxide (HrGO) with abundant nanopores provides longitudinal diffusion channels, enabling rapid Na+ diffusion along this direction, which solves the shortboard of bulk diffusion rate. Additionally, heterojunctions are considered a viable approach for enhancing fast Na+ storage performance by providing more storage sites and accelerating the kinetics of Na+ reaction, which solve the shortboard of ion reaction rate. Herein, we construct HrGO combined with CoSe2-NiSe2 heterojunctions has been rationally fabricated to synergistically enhance the ionic and electronic diffusion kinetics. As expected, the CoSe2-NiSe2/HrGO anode in SIBs shows an excellent fast-charging performance (392.4mAh/g at 15 A/g), surpassing most Co/Ni-based selenide anodes. Additionally, the assembled CoSe2-NiSe2/HrGO||NVP full cell delivers a high specific capacity of 116.1 and 95.4mAh/g at 0.1 and 20C, respectively, coupled with 97.8 % capacity retention rate for 100 cycles. Furthermore, we elucidate the mechanism of Na+ storage and fast transport through electrochemical kinetic analysis, in situ and ex situ characterizations, density functional theory (DFT) calculations, and distribution of relaxation times (DRT). Importantly, this study provides theoretical insights into accelerating rapid Na+ transfer.

Interface engineering-induced enhancements in sodium-ion batteries: A nexus of ZnS nanoparticles and reduced graphene oxide for augmented storage and conductivity

Due to the inherent sluggish kinetics and the pronounced volumetric expansion of zinc sulfide (ZnS), it has become a prevalent modification strategy to regulate its morphology and composite with graphene for using ZnS as anodes in sodium-ion batteries (SIBs). Nevertheless, the elucidation of mechanisms underpinning the electrochemical performance facilitated by graphene incorporation remains scant. To further describe the synergistic mechanism, the ultrafine ZnS nanoparticles anchored on reduced graphene oxide (rGO) were synthesized through a simple solvothermal method. Research shows that the ZSG (ZnS nanoparticles-reduced graphene oxide composite) electrode suggests superior rate capability, maintaining a reversible specific capacity of 228.6 mAh·g−1 upon returning from a high current density of 5 A·g−1. Furthermore, the nanoscale integration of ZnS particles with rGO synergistically mitigates the structural expansion of the ZSG electrode encountered during cycling, thereby decelerating the degradation of cyclic performance. Insights gleaned from first-principles calculations and comprehensive electrochemical evaluations reveal that the built-in electric field, engendered within the composite architecture, substantially augments charge transfer ability and mitigates the energy barriers impeding sodium ion (Na+) diffusion accordingly. Consequently, the methodology adopted for synthesis and the synergistic modification mechanism can proffer a reference for the design of advanced anode materials in SIBs.

N/P/O co-doped porous carbon derived from agroindustry waste of peanut shell for sodium-ion storage

Porous bio‑carbon from agroindustry waste behaves one of the most promising anode materials for sodium-ion batteries (SIBs) because of its high sodium storage capacity, low cost, sustainability, and low charge/discharge voltage platform. Herein, we have developed a new N/P/O co-doped porous hard carbon derived from peanut shell (PSCNP) synthesized via KOH activation, hydrothermal doping combined with carbonization method, using chitosan as nitrogen source, phytic acid as phosphorus source, and peanut shell as carbon and oxygen source. Through seriously regulating the calcination temperature, the optimal PSCNP-800 carbonization at 800 °C can well combine the advantages of the natural rich porous microstructure of peanut shells, large graphite interlayer spacing (0.379 nm), and short diffusion distance for sodium-ion. As an advanced anode for SIBs, the PSCNP-800 delivered a reversible capacity of 248.8 mAh g−1 after 100 cycles at 25 mA g−1. This work could provide a possible idea for the preparation of N/P/O co-doped porous hard carbon from low-cost agroindustry waste as anodes for SIBs.

Cu2-xSe@MXene (Ti3C2Tx) 2D layered heterostructure as an anode for high-performance sodium-ion batteries

With a notable focus on developing efficient sodium storage electrode materials, sodium-ion batteries (SIBs) have been identified as a promising contender in the pursuit of high-performing substitutes for lithium-ion batteries. Among varying sodium storage anode materials for SIBs, nonstoichiometric Cu2-xSe exhibits significant promise. This material stands out due to its ultrahigh electrical conductivity and theoretical sodium storage capacity. However, the practical implementation of Cu2-xSe-based anodes in SIBs is significantly impeded by their sluggish electrochemical reaction kinetics and severe pulverization during the repeated charge–discharge cycles. In the current research, we introduce a novel and straightforward methodology for the synthesis of a heterostructured SIBs anode material (Cu2-xSe@Ti3C2Tx), by coupling Cu2-xSe nanoparticles with two-dimensional (2D) layered MXene (Ti3C2Tx). The 2D layered Ti3C2Tx can provide abundant fast Na+ transport pathways, which effectively promote the ion transport kinetics in the composite anode. Moreover, the pulverization of Cu2-xSe can be effectively mitigated due to the interlamellar spatial confinement of the 2D layered MXene matrix. Consequently, the electrochemical performances of the Cu2-xSe-based anode are significantly improved. Concretely, the Cu2-xSe@Ti3C2Tx anodes demonstrate remarkable rate performance (248mAh g−1 at 10.0 A/g), along with commendable cycling stability, exhibiting a capacity retention of 92 % at 5.0 A/g after 750 cycles. A comprehensive assessment of the Cu2-xSe@Ti3C2Tx anode has been conducted by assembling a full SIB alongside a Na3V2(PO4)3 cathode. This comprehensive study underscores the significant potential of Cu2-xSe-based composite materials, positioning it as a promising candidate for future advancements in SIB technology.

High temperature induced abundant closed nanopores for hard carbon as high-performance sodium-ion batteries anodes

Hard carbon (HC) stands out as the preeminent anode material for sodium-ion batteries (SIBs) which are deployed in expansive energy storage infrastructures. Herein, the large enough graphene nanosheets interlayer and abundant nanopores with a diameter of ∼2.1 nm induced by adjusting the pyrolysis temperature in the thermosetting phenolic resin-derived hard carbon matrix to augment the performance of the sodium ion storage. The presence of sufficiently large carbon interlayers has been proven to provide active sites for reversible adsorption, enabling effective storage of sodium ions in the high-voltage slope region, while also promoting rapid Na+ transport. Meanwhile, forming abundant closed nanopores with larger sizes helps sodium ion storage in the low-voltage plateau region. In the optimized samples, the formation of sufficient long graphene nanosheets with a perfect crystal lattice, which further shrinks to form enclosed nanopores, effectively reduces defective sites and specific surface area. Additionally, the appropriate content of C-O and C=O functional groups contributes to an exceptional initial Coulombic efficiency (ICE) of up to 93%. Simultaneously, the optimized sample HC-1500 contributes to a remarkable plateau capacity of 294 mAh g-1 during the charging process (high reversible capacity of 403 mAh g-1 at 0.1 C). Moreover, based on the microstructure evolution and Na storage behavior of hard carbon, an “adsorption (27%) – filling (73%)” sodium storage mechanism that the sodium storage as a quasi-metallic sodium state is demonstrated. Consequently, this study will offer valuable insights for the development of hard carbon anodes tailored for high-energy practical SIBs, while also advancing the understanding of sodium storage mechanisms.

Unraveling the enhanced sodium-storage mechanism in a strongly bonded 2D honeycomb borophene/boron phosphide heterostructure

The growing modern demand for battery capacity is driving the development of high-capacity metal-ion battery anodes for future energy storage. Two-dimensional (2D) material-based heterostructures have shown advantages as alternative anodes due to their enhanced adsorption capacity. The lightweight nature of honeycomb borophene (HB) is beneficial for serving as a high-capacity anode but is constrained by structural instability arising from electron deficiency. In this study, using first-principles calculations, we propose a HB/boron phosphide (BP) heterostructure as an anode for both lithium-ion batteries and sodium-ion batteries (SIBs). The heterostructure engineering not only stabilizes the HB structure but also leads to a bonding heterostructure instead of common van der Walls type. The HB/BP demonstrates robust structural stability and reversibility when multiple ions are stored. In addition, the HB/BP offers stable storage sites and low diffusion barriers for lithium (0.31 eV) and sodium (0.28 eV), indicating rapid charging–discharging performance. Notably, the predicted maximum sodium storage capacity reaches 2402 mAh/g, surpassing that of the constituent monolayers and most 2D heterostructures. The underlying mechanism for high storage capacity is elucidated through detailed charge image model analysis, offering atomistic-scale insights for constructing high-capacity anodes. All results suggest that the presented HB/BP is a promising anode candidate for SIBs and opens an avenue for stabilizing HB in energy storage.

Realizing Ultrahigh Cycle Life Anode for Sodium-Ion Batteries through Heterostructure Design and Introducing Electro Active Polymer Coating.

Bi2S3 has attracted increasing attention in sodium-ion batteries (SIBs) for its high theoretical capacity and low discharge platform. However, the sodium storage performance of Bi2S3 is limited by poor electrical conductivity and volume expansion during cycling. Herein, we report a special polypyrrole (PPy)-coated MoS2/Bi2S3 (MBS@PPy) heterostructure composite obtained by hydrothermal reaction as an anode material for SIB. As a result, the MBS@PPy composites demonstrate exceptional electrochemical performance in SIB, exhibiting a high capacity of 361.1 mA h g-1 at 10 A g-1 and showcasing remarkable rate performance. Even under a high current density of 35 A g-1, the specific capacity remains stable at 280 mA h g-1 after 2,000 cycles. Furthermore, a successfully assembled Na3V2(PO4)3//MBS@PPy sodium-ion full cell can achieve an impressive specific capacity of approximately 400 mA h g-1 after 300 cycles at 0.5 A g-1. In MBS@PPy composites, the polypyridine coating not only improves the interfacial conductivity of nanorods but also effectively inhibits the agglomeration between nanorods due to large volume changes. The MoS2 heterostructure further inhibits the coarsening of the internal structure, improves electron transport and reaction kinetics, and increases the rate capability of the material. This work provides an effective strategy to develop energy storage materials with superior electrochemical properties.

Nanoarchitectured Fe3C@N-Doped C/FeVO4 as High-Performance Anode for Sodium-Ion Batteries.

Ferric vanadate exhibits potential as an attractive anode material for sodium-ion batteries (SIBs) due to the multiple oxidation states of vanadium and natural abundances of iron. However, the design and fabrication of high-performance ferric vanadate-based SIB anode materials with unique composite nanostructures are still challenging. Herein, a facile self-template method is reported to synthesize 1D nanostructured Fe3C@N-doped C/FeVO4 (Fe3C@NC/FeVO4) anode materials by the combination of morphology regulation with hybrid composite construction, for the first time. To this end, a 1D Fe, N-doped carbon nanotube (FeNC) is used as a template, followed by etching and re-growth to obtain the 1D Fe3C@N-doped C/FeVO4 nanostructure. The introduction of Fe3C can improve its electronic conductivity and enhance capacitive behavior. Additionally, the 1D nanostructure can effectively shorten the ions transport path and alleviate volume expansion during the charge-discharge processes. With these advantages, the SIBs using such anodes show a remarkable rate performance with a capacity of 325.4mAhg-1 at 0.1Ag-1, 150.6mAhg-1 at 5Ag-1, and excellent cycling stability with a reversible capacity of 139.6mAhg-1 at 1Ag-1 after 1500 cycles. This work offers a new strategy for the future development of SIBs with ferric vanadate-based anode.

Pomegranate Peel-Derived Hard Carbons as Anode Materials for Sodium-Ion Batteries

Exploring high-performance carbon anodes that are low-cost and easily accessible is the key to the commercialization of sodium-ion batteries. Producing carbon materials from bio by-products is an intriguing strategy for sodium-ion battery anode manufacture and for high-value utilization of biomass. Herein, a novel hard carbon (PPHC) was prepared via a facile pyrolysis process followed by acid treatment using biowaste pomegranate peel as the precursor. The morphology and structure of the PPHC were influenced by the carbonization temperature, as evidenced by physicochemical characterization. The PPHC pyrolyzed at 1100 °C showed expanded interlayer spacing and appropriate oxygen group content. When used as a sodium ion battery anode, the PPHC-1100 demonstrated a reversible capacity of up to 330 mAh g−1, maintaining 174 mAh g−1 at an increased current rate of 1 C. After 200 cycles at 0.5 C, the capacity delivered by PPHC-1100 was 175 mAh g−1. The electrochemical behavior of PPHC electrodes was investigated, revealing that the PPHC-1100 possessed increased capacitive-controlled energy storage and improved ion transport properties, which explained its excellent electrochemical performance. This work underscores the feasibility of high-performance sodium-ion battery anodes derived from biowaste and provides insights into the sodium storage process in biomass-derived hard carbon.

Design of cross-linked hard carbon with high initial coulombic efficiency for sodium-ion batteries anode

Cross-linked hard carbon materials (SFCzGLC1) were prepared from Shenfu bituminous coal (SFC) and glucose (GLC) via a one-step carbonization method. The relationship between the microstructure and Na+ storage behavior was explored. The initial coulombic efficiency (ICE) was related to surface defects. Owing to abundant porous structure and low defects, SFC3GLC1 delivered the highest reversible capacity of 413.1 mAh/g at 0.02 A/g with ICE ∼84 % and excellent cycling stability (89.4 % capacity retention over 200 cycles). This work provides a facile route to develop high-performance, low-cost carbon-based anodes for next-generation sodium-ion batteries (SIBs).

Bulk Alloy Anodes for Sodium‐ion Batteries

Sodium‐ion batteries (SIBs) are considered a promising candidate for next‐generation energy storage systems due to the abundance of available sodium resources. The practical application of SIBs critically depends on developing durable electrode materials with high capacity and long lifespan, particularly when it comes to finding suitable anode materials. Alloy‐type anodes are appealing for their high capacities owing to the multiple electron transfer alloying reaction mechanism, making them ideal for high‐energy‐density SIBs. However, the huge volume change during charge/discharge process can cause the active material pulverization to detach from the current collector, leading to poor cycling performance, especially for bulk alloy anodes. Despite this challenge, recent progress in bulk or micro‐sized alloy anodes for SIBs have shown promise. This review highlights the up‐to‐date advancements and research on bulk alloy‐based anode materials for SIBs, including synthetic strategies and electrochemical performance. The crucial role of bulk alloy anodes in advancing SIB technology is discussed, along with a summary of research on bulk alloy‐type anodes and their compounds for sodium storage. Strategies to improve the electrochemical performance of bulk alloy‐based anode materials are also explored. Additionally, the potential of multi‐component alloys and high‐entropy alloys as future research directions for alloy‐based anodes is proposed.

Steric Hindrance Engineering to Modulate the Closed Pores Formation of Polymer-Derived Hard Carbon for High-Performance Sodium-Ion Batteries.

The closed pores play a critical role in improving the sodium storage capacity of hard carbon (HC) anode, however, their formation mechanism as well as the efficient modulation strategy at molecular level in the polymer-derived HCs is still lacking. In this work, the steric hindrance effect has been proposed to create closed pores in the polymer-derived HCs for the first time through grafting the aromatic rings within and between the main chains in the precursor. The experimental data and theoretical calculation demonstrate that steric-hindrance effect from the aromatic ring side group can increase backbone rigidity and the internal free volumes in the polymer precursor, which can prevent the over graphitization and facilitate the formation of closed pores during the carbonization process. As a result, the as-prepared HC anode exhibits a remarkably enhanced discharge capacity of 340.3 mAh/g at 0.1 C, improved rate performance (210.7 mAh/g at 5 C) as well as boosted cycling stability (86.4 % over 1000 cycles at 2 C). This work provides a new insight into the formation mechanisms of closed pores via steric hindrance engineering, which can shed light on the development of high-performance polymer-derived HC anode for sodium-ion batteries.

Heterogeneous Interface Design with Oxygen Vacancy-Rich Assistance High-Capacity Titanium-Based Oxide Anode Materials for Sodium-Ion Batteries.

Researchers are paying more attention to sodium-ion batteries (SIBs) because of their abundant supply of sodium resources and affordable price. TiO2 offers excellent safety and a long lifespan as an anode material for SIBs. However, the process kinetics is slow due to its limited Na+ storage efficiency, weak conductivity, and irreversible Na+ capture. In order to address these issues, this review uses a mix of the template approach and the double-hydrolysis method to manage the structure and diffusion of TiO2-based anode materials by synthesizing FeTiO3/TiO2 heterostructured double-shell microspheres (FTO). Through the built-in electric field effect caused by their heterostructures, FTO materials improve reaction kinetics, boost electronic conductivity, and lower the diffusion energy barrier of Na+. Their distinctive double-shell structure can increase electrolyte infiltration, shorten the diffusion distance between ions and electrons, and accommodate volume expansion during cycling. Furthermore, the irreversible capture of Na+ and the unfavorable interactions between the surface active site and electrolyte can be successfully inhibited by FTO heterostructures. FTO has an exceptionally high capacity (reaching 362.7 mA h g-1 after 60 cycles at 20 mA g-1) and excellent cycle stability (with a decay rate of 0.0061% after 1000 cycles at 2 A g-1). The strategy of constructing heterogeneous interfaces assists with high-performance SIB anode design.

Integrating Multiple Redox‐Active Units into Conductive Covalent Organic Frameworks for High‐Performance Sodium‐Ion Batteries

The rational design of porous covalent organic frameworks (COFs) with high conductivity and reversible redox activity is the key to improving their performance in sodium‐ion batteries (SIBs). Herein, we report a series of COFs (FPDC‐TPA‐COF, FPDC‐TPB‐COF, and FPDC‐TPT‐COF) based on an organosulfur linker, (trioxocyclohexane‐triylidene)tris(dithiole‐diylylidene))hexabenzaldehyde (FPDC). These COFs feature two‐dimensional crystalline structures, high porosity, good conductivity, and densely packed redox‐active sites, making them suitable for energy storage devices. Among them, FPDC‐TPT‐COF demonstrates a remarkably high specific capacity of 420 mAh g−1 (0.2 A g−1), excellent cycling stability (~87% capacity retention after 3000 cycles, 1.0 A g−1) and high rate performance (339 mAh g−1 at 2.0 A g−1) as an anode for SIBs, surpassing most reported COF‐based electrodes. The superior performance is attributed to the dithiole moieties enhancing the conductivity and the presence of redox‐active carbonyl, imine, and triazine sites facilitating Na storage. Furthermore, the sodiation mechanism was elucidated through in‐situ experiments and density functional theory (DFT) calculations. This work highlights the advantages of integrating multiple functional groups into redox‐active COFs for the rational design of efficient and stable SIBs.

Integrating Multiple Redox-Active Units into Conductive Covalent Organic Frameworks for High-Performance Sodium-Ion Batteries.

The rational design of porous covalent organic frameworks (COFs) with high conductivity and reversible redox activity is the key to improving their performance in sodium-ion batteries (SIBs). Herein, we report a series of COFs (FPDC-TPA-COF, FPDC-TPB-COF, and FPDC-TPT-COF) based on an organosulfur linker, (trioxocyclohexane-triylidene)tris(dithiole-diylylidene))hexabenzaldehyde (FPDC). These COFs feature two-dimensional crystalline structures, high porosity, good conductivity, and densely packed redox-active sites, making them suitable for energy storage devices. Among them, FPDC-TPT-COF demonstrates a remarkably high specific capacity of 420 mAh g-1 (0.2 A g-1), excellent cycling stability (~87% capacity retention after 3000 cycles, 1.0 A g-1) and high rate performance (339 mAh g-1 at 2.0 A g-1) as an anode for SIBs, surpassing most reported COF-based electrodes. The superior performance is attributed to the dithiole moieties enhancing the conductivity and the presence of redox-active carbonyl, imine, and triazine sites facilitating Na storage. Furthermore, the sodiation mechanism was elucidated through in-situ experiments and density functional theory (DFT) calculations. This work highlights the advantages of integrating multiple functional groups into redox-active COFs for the rational design of efficient and stable SIBs.

Dual carbon confining SnO2 nanocrystals as high-performance anode for sodium-ion batteries

The increasing global demand for sustainable energy sources has driven research into sodium-ion batteries (SIBs) for large-scale energy storage. However, their electrochemical performance is hindered by poor reaction kinetics and significant volume expansion in electrode materials. In this work, we developed a dual-carbon-confined SnO2 nanocrystal anode (CNTs@SnO2@NC) designed for high-performance SIBs. This innovative structure uses carbon nanotubes (CNTs) and a nitrogen-doped carbon (NC) coating to stabilize SnO2, ensuring structural integrity during charge/discharge cycles. The CNTs network in CNTs@SnO2@NC can alleviate the agglomeration of SnO2 nanocrystals to a certain extent; With its superior electronic conductivity, CNTs can enhance the anode's conductivity and function as an electronic highway; The sodiophilic properties and good electrical conductivity of CNTs enable sodium ions to migrate rapidly on the surface of the nanotubes. Moreover, numerous external defects and active sites generated by nitrogen doping enhance the sodium ion absorption capabilities; The existence of nitrogen-doped carbon coating can effectively accommodate the volume changes of SnO2 and enhance the structural stability of CNTs@SnO2@NC composites during the repeated charge and discharge cycles. As a result, the CNTs@SnO2@NC composite demonstrates excellent electrochemical performance, achieving capacity of 235 mAh g−1 at 0.1 A g−1 over 100 cycles and 102 mAh g−1 at 1.0 A g−1 over 300 cycles. In a full-cell configuration with a Na3V2(PO4)3 cathode, it delivers 38 mAh g−1 at 100th cycle at 0.1 A g−1. This study underscores the substantial improvements achieved by dual-carbon confinement for high-performance SIB anodes, offering a promising direction for future anode material design.