CHEMICAL ENGINEERING JOURNAL
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2025
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IF 13.2
Peng-Xing Xie,Qing-Yuan Zhao,Haojie Dong,Tao Long,Meng-Sha Ding,Bin Xie,Xiao-Feng Wang,Wei Ling,Mengting Liu,Xiong-Wei Wu,Peng-Fei Wang,Xian-Xiang Zeng
Delivery of high energy density in polyanion compound-Na 3 V 2 (PO 4 ) 3 based on three-electron redox is still challenging because of their controversial multi-electron reaction mechanism and unsatisfactory electrochemical reversibility. Herein, the reversible V 4+ /V 5+ redox ( ca. 4.0 V) could be successfully activated in Na 4 VFe(PO 4 ) 3 cathode material through a Na-rich strategy, demonstrating a reversible specific capacity of 154.7mAh g −1 at 0.1C and 90.3mAh g −1 after 800 cycles at 20C, with 80 % of the initial capacity retained. The entire electrochemical reaction undergoes a highly recoverable phase transition by in-situ X-ray diffraction. Impressively, the Na-rich strategy could not only allow Na2 site to be occupied to activate the V 4+ /V 5+ redox pair confirmed by X-ray absorption near-edge structure spectroscopy, but also enable Na + transportation across the generated vacancies rather than synergistic Na + diffusion. This work provides rational design strategy of multi-electron transfer reaction in high-energy sodium-ion batteries.
研究领域:
材料科学
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电化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2023
·
IF 9.9
Yuxiang Chen,Xiangyue Liao,Peng Wang,Ji Chen,Xiaoqin Zhang,Xingqiao Wu,Sean C. Smith,Dunmin Lin,Xin Tan,Qiaoji Zheng
The stable three-dimensional framework and high operating voltage of sodium superionic conductor (NASICON)-type Na 3 V 2 (PO 4 ) 3 has the potential to work with long cycle life and high-rate performance; however, it suffers from the poor intrinsic electronic conductivity and low energy density . Herein, Ga 3+ is introduced into Na 3 V 2 (PO 4 ) 3 to activate the V 4+ /V 5+ redox couple at a high potential of 4.0 V for enhancing energy density of the materials (Na 3 V 2-x Ga x (PO 4 ) 3 ). After the partial substitution of Ga 3+ for V 3+ , three redox couples (V 2+ /V 3+ , V 3+ /V 4+ and V 4+ /V 5+ ) of V are reversibly converted in the voltage range of 1.4–4.2 V, suggesting multi-electrons (>2e − ) involved in the reversible reaction, and simultaneously the electronic conductivity of the materials is effectively enhanced. As a result, the cathode with x = 0.75 exhibits excellent electrochemical properties: in the voltage range of 2.2–4.2 V, delivering an initial capacity of 105 mAh/g at 1C with a capacity retention rate of 92.3% after 400 cycles, and providing a stable reversible capacity of 88.3 mAh/g at 40C; and in the voltage range of 1.4–4.2 V, presenting the reversible capacity 152.3 mAh/g at 1C (497.6 Wh kg −1 ), and cycling stably for 1000 cycles at 20C with a capacity decay of 0.02375% per cycle. It is found that the Na 3 V 2-x Ga x (PO 4 ) 3 cathodes possess the sodium storage mechanism of single-phase and bi-phase reactions. This investigation presents a useful strategy to enhance the energy density and cycling life of NASICON-structured polyanionic phosphates by activating high-potential V 4+ /V 5+ redox couple.
研究领域:
材料科学
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电化学
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能源存储
✓ 已验证
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2025
·
IF 9.7
Binghao Lin,Xu Wu,Xuejie He,Jiaxin Ye,Yuqin Song,Ping Jiang,Linxuan Bai,Xiangyue Liao,Yangjie Li,Yu Huo,Qiaoji Zheng,Heng Zhang,Dunmin Lin
Na 3 V 2 (PO 4 ) 3 (NVP) with typical NASICON structure is highly regarded as one of the most appealing cathodes for sodium-ion batteries (SIBs) for their excellent structural stability; however, the poor electronic conductivity and irreversible phase transition at high voltage (∼4 V) for the material result in poor rate capabilities and significant capacity degradation during electrochemical reactions. Herein, the high-entropy doping strategy of introducing six types of metal ions into the V-sites in Na 3 V 2 (PO 4 ) 3 is used to design a high-performance cathode of Na 3 V 1.73 (Mn, Ca, Mg, Al, Zr) 0.05 Nb 0.02 (PO 4 ) 3 (HE-NVP) for SIBs. After the high-entropy doping, a reversible V 4+ /V 5+ redox pair is activated at high voltage of ∼4 V, which significantly contributes to the enhancement of energy density and operating voltage. Moreover, after high entropy doping, the single solid solution phase transition in high voltage range is induced, effectively improving the material’s structural stability and exhibiting very small volume change of 1.1 % during the Na + extraction/insertion. Based on the unique advantages mentioned above, the high-entropy HE-NVP exhibits a superior discharge capacity of 122.1 mAh g −1 at a current rate of 0.5C and maintains a remarkable capacity retention of 90.1 % after 500 cycles at a rate of 5C. This work provides a useful reference for designing advanced cathodes for SIBs by regulating high entropy doping.
研究领域:
材料科学
·
电化学
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储能技术
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电池技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子