ACS Energy Letters
·
2019
·
IF 16.331
Hongming Yi,Le Lin,Moxiang Ling,Zhiqiang Lv,Rui Li,Qiang Fu,Huamin Zhang,Qiong Zheng,Xianfeng Li
Na3V2(PO4)2F3 has been emerging as one of the most promising cathodes for sodium-ion batteries due to its stable NASICON structure and fast Na+ diffusion. However, present methods for preparation of Na3V2(PO4)2F3 suffer from either high energy consumption or generating poor rate performance. Herein, a cost-effective solvothermal–ball-milling method is proposed to solve the problem. In the solvothermal process, the morphology of Na3V2(PO4)2F3 varies from 0D to 3D with changing pH, in which 3D Na3V2(PO4)2F3 at pH = 3 shows optimal purity due to the fastest growth rate. With Ketjenblack (KB) coating by short-time ball-milling, the Na3V2(PO4)2F3 can be further nanosized with a highly graphited carbon coating layer. The purest Na3V2(PO4)2F3@KB from pH = 3 exhibited an initial capacity of 138 mAh g–1 @ 0.5 C and 122 mAh g–1 @ 40 C. Moreover, ultrahigh dosage over an 80 mmol of V source in one 100 mL Teflon-lined autoclave has been achieved for the first time.
研究领域:
材料科学
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储能
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电化学
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纳米材料
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电池技术
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DOI
高影响因子
Journal of Energy Storage
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2026
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IF 10.7
Jiaqi Pan,Shaokang Guo,Xingyu Ni,Xutong Sun,Wenhao Yue,Yongchen Kong,Yonghui Ma,Chunliang Zhou,Junnan Liu
Sodium-ion batteries (SIBs) are considered a promising alternative to lithium-ion batteries (LIBs) due to their abundant resources and low cost. However, the relatively large radius and mass of sodium ions can lead to structural degradation and volume changes in the electrode materials during charging and discharging processes, which limits their practical applications. In this paper, we successfully prepared carbon and MnO 2 co-coated Na 3 V 2 (PO 4 ) 2 F 3 (NVPF/C@ M-x, x = 0, 1, 3, 5 wt%) cathode materials using sol-gel method and suspension coating method. We systematically studied the physical and chemical effects of the MnO 2 coating, as well as the electrochemical performance of the materials. The results demonstrate that an optimal MnO₂ coating (1 wt%) forms a uniform interfacial layer, which not only suppresses Na + dissolution and side reactions but also enhances electronic conductivity and structural stability. NVPF/C@M-1 exhibits a reversible specific capacity of 129.09 mAh g −1 at 0.1C and maintains a capacity of 59.44 mAh g −1 at 10C. Furthermore, after 300 cycles at 1C and 500 cycles at 5C, the capacity retention rates are 85.96% and 89.34%, respectively. Kinetic analysis reveals that the MnO 2 coating significantly reduces the charge transfer resistance (R ct ) and increases the sodium ion diffusion coefficient (D Na+ ), thereby optimizing the rate performance and cycling stability of the materials. Additionally, the MnO 2 and C co-coating structure significantly improves the low-temperature performance, with the NVPF/C@M-1 electrode maintaining 90.43% capacity retention even at −30 °C, far superior to the uncoated sample's 64.13%. The NVPF/C@M-1 cathode demonstrates significantly enhanced overall performance in sodium-ion full-cell tests. It delivers an initial discharge capacity of 107.78 mAh g −1 at 1C, maintains a capacity retention rate of 95.07% after 100 cycles, and retains a discharge capacity of 81.63 mAh g −1 even at the high rate of 5C. This study provides an effective strategy for developing high-performance cathode materials for sodium-ion batteries.
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产品关联
DOI
高影响因子
RSC Advances
·
2019
·Vol. 9
·期 53
·30628-30636
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IF 3.049
Mingxue Wang,Xiaobing Huang,Haiyan Wang,Tao Zhou,Huasheng Xie,Yurong Ren
Na3V2(PO4)2F3 (NVPF) with NASCION (Na superionic conductor) is recognized as a potential cathode material owing to its high theoretical capacity. However, the electronic conductivity of NVPF is much lower than its ionic conductivity, which seriously affects the properties of this material. The carbon layer can be used as the conductive medium to enhance the conductivity of NVPF. In this study, we propose a single-step solid-state reaction method based on mechanical activation with pitch as the carbon source to synthesize NVPF/C composites. The crystallographic structure and morphology of all as-prepared samples were investigated by XRD, Raman spectroscopy, BET measurement, thermal analysis, SEM and TEM. Furthermore, the electrochemical performance and kinetic properties were analyzed by CV, galvanostatic charge–discharge and EIS tests. These tests outcomes demonstrated that the NVPF/C-2 composite with a carbon content of 12.14 wt% showed an excellent rate performance and cycle stability. It presented reversible capacities of 103 and 95 mA h g−1 at 0.2 and 10C, respectively, and an outstanding retention of 91.9% after 500 cycles at 5C. These excellent properties of the NVPF/C-2 composite are attributed to its high ion diffusion coefficient and small charge transfer impedance.
研究领域:
材料科学
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电化学
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能源存储
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无机固体化学
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纳米材料
✓ 已验证
DOI
高影响因子
ACS Applied Materials & Interfaces
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2022
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IF 10.383
Yue Zhang,Wenjun Song,Yakun Tang,Dianzeng Jia,Yudai Huang
Na3V2(PO4)2F3 is one of the most studied polyanion type cathode materials for sodium-ion batteries (SIBs) and offers great promises. However, the inferior rate capability induced by its sluggish diffusion of electrons and ions greatly limits the practical application of electrode materials in SIBs. Herein, we develop an efficient method to fabricate in situ carbon-coated Na3V2(PO4)2F3 nanosheets by using cost-effective amylopectin. The amylopectin not only could induce the nucleation of Na3V2(PO4)2F3 along its backbone to form a 2D nanostructure, but also act as a source of amorphous carbon for in situ coating on the active material surface. The composite exhibits extraordinary rate capability (104 mA h g–1 at 40 C, 51 mA h g–1 at 150 C) and desirable cycling stability. Such satisfactory achievements, especially the superior rate performance, should be ascribed to its unique 2D nanostructure which shortens the Na+ diffusion length, and the in situ carbon coating endows the composites with effective electron transport. Even applied to full cells, the obtained devices still display an exceptionally high energy density (94.8 W h kg–1), high power density (7295 W kg–1), and excellent cyclic stability.
研究领域:
材料科学
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储能
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电化学
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纳米材料
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2021
·Vol. 47
·期 12
·17192-17201
·
IF 4.527
Weikai Zhu,Kang Liang,Yurong Ren
NASICON-type Na 3 V 2 (PO 4 ) 2 F 3 (NVPF) is proposed to be a potential cathode material for sodium-ion battery because of its good structural stability , relatively high capacity and voltage platform. Nonetheless, the poor-rate performance, resulting from its low conductivity, has become a massive obstacle to its practical application. In this work, carbon coating together with morphology controlling were introduced to solve the issue of NVPF. This experiment used a hydrothermal method to prepare Na 3 V 2 (PO 4 ) 2 F 3 @C (NVPF@C) and explored the impact of surfactants (polyvinylpyrrolidone (PVP)) on the positive material performance of sodium-ion battery. Through various characterisation, NVPF@C compared its performance with that of untreated products, and verified that appropriate surfactant modification could enhance the performance of the electron conduction and sodium ion diffusion, thus effectively improved the performance of NVPF. Through comparison, it was found that appropriate surface modification with PVP can achieve the effects of specific crystal surface exposure and clusters of porous micron ball structure, and improve the electrochemical performance of NVPF best. Under the charge and discharge ratio of 0.2C, its initial reversible capacity was 127.8 mA h g −1 . After 100 cycles, its discharge capacity was 106.1 mA h g −1 , and the cycling retention rate reached 82.8%. Compared to the original NVPF, its performance has been dramatically improved.
研究领域:
材料科学
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电化学
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储能技术
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纳米材料
✓ 已验证
DOI
高影响因子
JOURNAL OF ELECTROANALYTICAL CHEMISTRY
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2026
·
IF 4.6
Qing Xu,Guojie Wu,Jiamin Deng,Xi Ke,Zhicong Shi,Liying Liu
Large K + ions act as structural pillars to enhance crystal stability. • Mg doping introduces additional vacancies to accelerate Na + diffusion. • K Mg co-doping significantly enhances rate performance and cycling stability at 4.5 V. The polyanionic compound Na 3 V 2 (PO 4 ) 2 F 3 (NVPF) cathode material has attracted extensive attention due to its high theoretical specific capacity (128 mAh g −1 ) and energy density (500 Wh kg −1 ). The primary bottleneck for NVPF is the low intrinsic electronic conductivity, which results in poor long cycling and rate performance. A K Mg co-doped Na 2.92 K 0.08 V 1.95 Mg 0.05 (PO 4 ) 2 F 3 (NKVMPF) cathode material is designed in this work to address the above problem. K Mg co-doping improves the Na + diffusion kinetics and crystal structure stability of NVPF due to the increased lattice volume, introduced additional vacancies, and the pillar supporting role of K + with larger radius. At a potential window of 2.0 V–4.5 V, the NKVMPF delivers superior rate performance and long-term cycle ability compared to NVPF, with a specific discharge capacity of 66.9 mAh g −1 at the high current rate of 20C and a capacity retention of 81.1% after 250 cycles at 0.2C. This work provides a binary doping strategy suitable for polyanion cathode materials and offers a new perspective for the development of high-performance cathode materials for sodium-ion batteries (SIBs).
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DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
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2025
·
IF 6.3
Nianxue Dong,Yongguang Zhang,Xianyue Zhang,Jiawei Fan,Haipeng Li,Baoe Li
Na 3 V 2 (PO 4 ) 2 F 3 (NVPF) is a promising cathode material for sodium-ion batteries owing to its impressive theoretical capacity, elevated operating voltage, and stable structure. However, its practical utilization remains limited owing to its poor electronic conductivity. To overcome this issue, an Sn-doped and reduced graphene oxide (rGO)–coated NVPF cathode is successfully prepared using the sol–gel method. Sn substitution moderately widens the lattice spacing, facilitating intrinsic electronic conductivity, while rGO coating provides continuous conductive pathways along the particle surfaces, suppressing polarization and enhancing external electron transport. Herein, the optimized Na 3 V 1.93 Sn 0.07 (PO 4 ) 2 F 3 @rGO (NVSnPF-0.07@rGO) cathode reached a specific capacity of 123.0 mAh g −1 at 1 C, with a rate capability of 74.4 mAh g −1 at 30 C, which is superior to those of the unmodified NVPF cathode. The capacity retention remains at 80.7 % after 2500 cycles at 30 C. Density functional theory analysis reveals that Sn doping is beneficial for improving the electrical conductivity of NVPF. Finally, the NVSnPF-0.07@rGO//HC (hard carbon) full cell reaches a discharge output of 92.2 mAh g −1 at 1 C after long-term cycling and a Coulombic efficiency of ∼100 %. The evidence presented in this study provides a framework for advancing the functional properties of cathode materials.
研究领域:
材料科学
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电化学
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储能技术
·
纳米材料
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产品关联
DOI
高影响因子
ELECTROCHIMICA ACTA
·
2022
·
IF 7.336
Wenjie Zhao,Weigang Wang,Guorong Hu,Ke Du,Zhongdong Peng,Xudong Zhang,Huan Li,Zijun Fang,Yanbing Cao
Porous Na 3 V 2 (PO 4 ) 2 F 3 (NVPF) with micro-nano structure was prepared by a simple deep-eutectic solvent method with good crystallinity and uniformity. Surface modification was used to produce carbon-coated NVPF (NVPF/C). The unique morphologic architecture and surface modification improve the structural stability and interfacial chemical stability of NVPF, ensuring the excellent rate performance and cycle stability of NVPF/C. At 120 °C, secondary microspheres NVPF composed of nanoparticles are successfully synthesized. By liquid phase reaction in a deep-eutectic solvent X-ray diffraction analysis reveals that these microspheres have good crystallinity . The NVPF/C with an amorphous fluorocarbon coating layer is constructed by pyrolysis of polytetrafluoroethylene (PTFE). The mesoporous structure and the existence of the coating layer are clearly obvious under the high-definition transmission electron microscope. The amorphous fluorocarbon layer enhances the reversibility and transmission ability of Na + , improving the electrochemical kinetics. And the obtained NVPF/C cathode material displays high-rate performance. The as-prepared NVPF/C-F composites with 6 %wt coating of PTFE have a specific capacity of 110.6 mAh g −1 at 10 C, 106.4 mAh g −1 at 20 C and 94.6 mAh g −1 at 50 C. The capacity retention rate is 90.4 % after 700 cycles at 20 C. This research provides a facile and inexpensive approach for getting high-rate performance sodium-ion battery cathode materials.
研究领域:
材料科学
·
电化学
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DOI
高影响因子
CERAMICS INTERNATIONAL
·
2020
·
IF 3.83
Mingxue Wang,Kun Wang,Xiaobing Huang,Tao Zhou,Huasheng Xie,Yurong Ren
To improve the intrinsic electronic conductivity of Na 3 V 2 (PO 4 ) 2 F 3 (NVPF), zirconium (Zr) was introduced into the NVPF/C compound through a carbothermal reduction reaction with citric acid as the carbon source. The effects of Zr 4+ doping on the crystal structure and morphology of the as-prepared materials were analyzed. Electrochemical and kinetic properties of the samples were investigated by galvanostatic charge-discharge, CV and EIS test. It is confirmed that moderate Zr 4+ doping can improve the electrochemical performance of NVPF. Among all Na 3 V 2-x Zr x (PO 4 ) 2 F 3 /C (x = 0, 0.01, 0.05, 0.1) samples, Na 3 V 1·95 Zr 0·05 (PO 4 ) 2 F 3 /C shows the best rate and cycle performance. It exhibits the highest specific capacity of 121.8 and 110.3 mAh/g at 0.2 and 10 C, respectively, and maintains a capacity retention of approximately 83.6% after 1000 cycles at 5 C. The kinetic properties results show that the excellent electrochemical performance of Na 3 V 1·95 Zr 0·05 (PO 4 ) 2 F 3 /C can be attributed to the increase in electronic conductivity and ion diffusion coefficient .
研究领域:
材料科学
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电化学
·
储能
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DOI
高影响因子
ACS Applied Energy Materials
·
2022
·
IF 6.959
Xiaofei Sun,Zikang Wang,Qiongdan Hu,Xuesong Mei,Yue Zhao,Anastase Ndahimana,Tao Geng,Jianlei Cui
The abundant reserves of sodium resources and its low price make the desire to build energy storage systems on room-temperature rechargeable sodium batteries. The current challenge exists in exploring high-performance key materials, especially cathode materials. Vanadium-based phosphates have attracted extensive attention as a class of promising cathode materials for sodium batteries due to their stable structure, large capacity, and high voltage advantages. In this paper, sodium vanadium oxyfluorophosphate, Na3V2(PO4)2F3–2yO2y (0 ≤ y < 1), is exploited to improve its electrochemical performance through oxygen tuning. The effect of oxygen amount on the structure, morphology, and performance is comprehensively and comparatively investigated. It is found that the optimal electrochemical performance is achieved in Na3V2(PO4)2F2O when y = 0.5. Its specific discharge capacity at 0.1, 0.5, 1, 8, and 20 C is 125, 111, 101, 71, and 58 mA h g–1, respectively. The superior rate performance and good cyclability are ascribed to the low impurity, mixed V3+/V4+ valence state, small particle size, suitable residual carbon coating, low charge transfer resistance, fast Na+ diffusion, and particularly the regulation of charge/discharge potentials as well as polarizations due to proper oxygen tuning.
研究领域:
储能
·
电化学
·
材料科学
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电池技术
✓ 已验证
DOI
高影响因子
Journal of Materials Chemistry A
·
2025
·
IF 9.5
Chen Wu,Yuxing Xu,Jiechen Song,Chunshan Wang,Qiangqiang Tan
Sodium vanadium fluorophosphate (Na3V2(PO4)2F3, NVPF) as a polyanionic cathode material has attracted considerable interest due to its high operating voltage and robust structural framework. However, its practical application at high rates is severely hindered by intrinsically low electronic conductivity and sluggish ionic diffusion kinetics. This work proposes a stepwise engineering strategy that addresses charge transport limitations from the electrode architecture to the bulk material. Specifically, construct a three-dimensional conductive network of vertically aligned carbon nanotubes (VA-CNTs) within the NVPF cathode via a magnetic-field-assisted technique, combined with K/Sc dual-element bulk doping. It is demonstrated that the VA-CNTs significantly reduce interfacial resistance and provide direct pathways for electronic diffusion, outperforming conventional randomly dispersed CNTs. Furthermore, the co-doping of K and Sc synergistically expands sodium-ion migration channels and optimizes the electronic structure of the material, thereby enhancing intrinsic conductivity. This strategy endows the modified KS-3VA-CNTs-NVPF cathode with remarkable high-rate performance and impressive cycling stability: a capacity retention of 90.33% after 500 cycles at 5 C, significantly surpassing the 67.28% of the unmodified NVPF, and a capacity retention of 75.94% after 1000 cycles at a high rate of 30 C. This work not only offers an effective route for developing high-performance NVPF cathodes, but also presents a universal stepwise engineering strategy that opens a new paradigm for designing other high-rate electrode materials.
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产品关联
DOI
高影响因子
Frontiers in Chemistry
·
2019
·
IF 3.782
Hao Guo,Yong Hu,Xiaoping Zhang,Rongliang Zhang,Dong Hou,Yulei Sui,Ling Wu
In this paper, we report a facile one-step hydrothermal method to synthesize tetragonal Na3V2(PO4)2F3@C particles which are connected by carbon nanotubes (CNTs) networks, using water as hydrothermal solvents. In this strategy, the reduction and crystallization of materials are carried out in the hydrothermal process (180°C, 12 h), no additional heat treatment is required. The well-crystallized Na3V2(PO4)2F3 tetragonal grains (5–10 μm) are coated with amorphous nano-carbon and connected by highly conductive CNTs. The addition of CNTs can not only improve the conductivity of materials but also effectively inhibit the Na3V2(PO4)2F3 grains over growth. The Na3V2(PO4)2F3@C/CNTs composite possesses very flat charge/discharge platforms of 3.6 and 4.1 V. The sample exhibits an initial discharge specific capacity of 120.2 and 74.3 mAh g−1 at 0.1 and 10 C rate, respectively, and shows excellent cyclical stability. The composite owns excellent electrochemical performances owing to the three-dimensional highly conductive network which is co-constructed by the CNTs and nano-carbon coating layer.
研究领域:
材料科学
·
电化学
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纳米科技
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能源存储
·
无机化学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）