INORGANIC CHEMISTRY
·
2025
·
IF 4.7
Weishun Jian,Xinyu Hu,Jinqiang Gao,Jingyao Zeng,Yu Mei,Haoji Wang,Ningyun Hong,Jiangnan Huang,Kai Wang,Wentao Deng,Guoqiang Zou,Hongshuai Hou,Hongyi Chen,Xiaobo Ji
Na4Fe3(PO4)2(P2O7) (NFPP) is a promising cathode material for sodium-ion batteries with cost-effectiveness and structural stability. However, its electrochemical behaviors are seriously hindered by its [P2O7] distortion at high voltage. To address this challenge, we introduce a distortion criterion and optimize the local crystal field environment by incorporating Cr3+ into Fe3 sites adjacent to [P2O7]. This substitution elongates Fe1–O bonds, enhances Fe1 activity, and suppresses [P2O7] distortion, facilitating fast Na+ diffusion and structural reversibility, as validated by X-ray absorption fine structure (XAFS) and density functional theory (DFT) calculations. Based on c-axis changes during high-voltage operation, a quantitative method for assessing [P2O7] distortion is proposed and confirmed by operando X-ray diffraction (XRD). The optimized NFPP-0.15Cr exhibits exceptional rate performance (91.74 mAh g–1 at 50C), long-term cycling stability (88.81% capacity retention after 10,000 cycles at 50C), and wide temperature tolerance (−40 to 60 °C). This study provides a strategic approach for designing high-performance iron-based mixed phosphate cathodes, advancing their practical application in sodium-ion batteries.
研究领域:
材料科学
·
能源存储
✓ 已验证
DOI
PubMed
高影响因子
Energy Storage Materials
·
2022
·
IF 20.831
Wen Ren,Mulan Qin,Yifan Zhou,Huang Zhou,Jue Zhu,Junan Pan,Jiang Zhou,Xinxin Cao,Shuquan Liang
The development of low-cost and long-lifespan cathode materials for sodium-ion batteries has been one of the key issues for the success of grid-scale energy storage. Na 4 Fe 3 (PO 4 ) 2 P 2 O 7 has received a great deal of attention due to its high theoretical capacity, good structural stability, and high abundance of resources. Herein, hierarchical carbon decorated Na 4 Fe 3 (PO 4 ) 2 P 2 O 7 nanofibers are designed and fabricated through a feasible electrospinning technique and subsequent pyrolysis. The free-standing Na 4 Fe 3 (PO 4 ) 2 P 2 O 7 /C electrode exhibits good mechanical flexibility, together with high electronic conductivity and ultrafast Na + migration in sodium-ion batteries, leading to high reversible capacity (118 mA h g −1 at 0.2 C), superior cycling stability (79.6% of capacity retention over 10,000 cycles at 10 C) and excellent rate performance (64 mA h g −1 at 20 C). The full cell assembled with Na 4 Fe 3 (PO 4 ) 2 P 2 O 7 /C cathode and hard carbon anode, shows reversible capacity of 126.4 mA h g −1 with high working voltage of 2.9 V at 20 mA g −1 . Such an effective concept of fabricating hierarchical carbon-decorated electrodes for SIBs is expected to accelerate the practical applications of high-rate flexible energy storage devices.
研究领域:
材料科学
·
储能技术
·
纳米技术
·
电池技术
✓ 已验证
DOI
高影响因子
Batteries-Basel
·
2024
·Vol. 10
·期 4
·121
·
IF 4.6
Ao Xiang,Deyou Shi,Peng Chen,Zhongjun Li,Quan Tu,Dahui Liu,Xiangguang Zhang,Jun Lu,Yan Jiang,Ze Yang,Pei Hu
Developing cost-effective cathode materials is conducive to accelerating the commercialization of sodium-ion batteries. Na4Fe3(PO4)2P2O7(NFPP) has attracted extensive attention owning to its high theoretical capacity, stable structure, and low cost of raw materials. However, its inherent low conductivity hinders its further application. Herein, carbon-coated NFPP nanospheres are anchored to crumpled MXene nanosheets by an electrostatic self-assembly; this cross-linked structure induced by CTAB not only significantly expands the contact area between particles and improves the electronic conductivity, but also effectively reduces the aggregation of NFPP nanoparticles. The as-designed Na4Fe3(PO4)2(P2O7)@C/Ti3C2Tx(NFPP@MX) cathode exhibits a high discharge capacity (106.1 mAh g−1g at 0.2 C), good rate capability (60.4 mAh g−1at 10 C), and a long-life cyclic stability (85.2% capacity retention after 1000 cycles at 1 C). This study provides an effective strategy for the massive production of high-performance NFPP cathodes and broadens the application of MXene in the modification of other cathode materials.
研究领域:
材料科学
·
电化学
·
能源存储
✓ 已验证
DOI
高影响因子
Small
·
2025
·
IF 12.1
Xin Chen,Jiahui Wu,Jingyao Zeng,Caiyan Shen,Yuejun Wang,Yangyang Xie,Guorong Hu,Ke Du,Zhongdong Peng,Yanbing Cao
Due to the strong electronegativity of P in the anion group and the strong P─O covalent bond, NFPP exhibits low electronic and ionic conductivity, hindering its rate capability. A doping modification strategy of selecting La 3+ with a large ion radius at Na site has been designed, and the nano-micro architectural Na 4-3x La x □ 2x Fe 3 (PO 4 ) 2 (P 2 O 7 )/C (0≤x≤0.04) cathode material with Na vacancies is successfully synthesized via a scalable preparation route. Introducing positively charged substitutional point defects and charged vacancies through doping La 3+ not only broadens the Na + transport channels but also reduces lattice stress and stabilizes the crystal bulk structure during long-term cycling for La 3+ as pillars. Additionally, high valence La 3+ doping enhances the effective charge carrier concentration and improves material conductivity. Consequently, the kinetic performance of Na + migration is significantly enhanced. The optimal Na 3.91 La 0.03 □ 0.06 Fe 3 (PO 4 ) 2 (P 2 O 7 )/C (NFPP/C-La3) exhibits the best electrochemical performance. The synthesized NFPP/C-La3 exhibits excellent rate performance (99.45 mAh g −1 at 20 C) and long-term cycle stability (92.36% of capacity retention over 1000 cycles at 10 C). These results provide the importance and prospect of the high valence ion doping for NFPP/C with high rate stability.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Materials Chemistry A
·
2026
·
IF 9.2
shu zhao,浩 李,shuo shi,Chao Wang,Xiu Song Zhao
Sodium iron pyrophosphate (NFPP) is a cost-effective and safe cathode material for sodium-ion batteries (NIBs). However, NFPP suffers from low electron conductivity and sluggish Na+ diffusion kinetics, resulting in a poor rate capability. Here, we show that partial co-substitution of V3+ and Al3+ for Fe2+ synergistically enhances the rate capability of NFPP with improved Na+ storage capacity. The V3+/Al3+ co-substitution narrows the band gap energy of NFPP from 2.99 to 1.53 eV to increase electron conductivity, reduces Na+ diffusion energy barrier from 0.529 eV to 0.398 eV to enhance Na+ diffusivity, leads to the formation of Na vacancies to further facilitate Na+ transport, and improves Na+ storage capacity is because of enhanced electroactivity of the Fe2+/Fe3+ couple. At 0.1, 5 and 10C, the Na+ storage capabilities of the V3+/Al3+ co-substituted NFPP cathode are 120, 85 and 72 mAh g−1, respectively. At 5C, this electrode maintains 81% capacity after 1000 cycles. A full cell fabricated with the co-substituted NFPP as the cathode and a commercial hard carbon (HC) as the anode delivers a Na+ storage capacity of 87 mAh g−1 with 77% capacity retention after 100 cycles at 1C, outperforming a counterpart full cell fabricated with NFPP as the cathode and the anode and electrolyte.
✓ 已验证
产品关联
DOI
高影响因子
NEW JOURNAL OF CHEMISTRY
·
2023
·Vol. 47
·期 21
·10153-10161
·
IF 3.3
Kangsheng Shi,Wensheng Yang,Qiaodan Wu,Xingke Yang,Ruiya Zhao,Ziqiang She,Quan Xie,Yunjun Ruan
The structural deformation during the embedding/de-embedding of K+ with a large ionic size is an important factor limiting the development of potassium-ion batteries (PIBs). The iron-based mixed polyanionic material Na4Fe3(PO4)2(P2O7) (NFPP) makes an excellent cathode material for PIBs due to its low cost, non-toxicity, suitable theoretical capacity, and stable structure. Here, a 3D reduced graphene oxide network wrapped NFPP (NFPP@rGO) was synthesized using a freeze-drying and subsequent annealing treatment. The NFPP@rGO material as a PIB cathode achieves a high discharge specific capacity of 119.1 mA h g−1 at 0.1C and 80.3 mA h g−1 even at 2C current density, and retains 82.1% of its initial capacity after 500 cycles. Ex situ XPS and XRD are utilized to understand the K+ storage mechanism of NFPP@rGO in PIBs. The superior electrochemical properties are due to the 3D reduced graphene oxide network, which improves the material's electrical conductivity and K+ diffusion rate, and stabilizes structural deformation during charge and discharge. These results indicate the feasibility of the NFPP@rGO cathode material for PIBs.
研究领域:
材料科学
·
能源存储与转换
✓ 已验证
DOI
高影响因子
JOURNAL OF POWER SOURCES
·
2021
·
IF 9.127
Jianhua Zhang,Linbin Tang,Yu Zhang,Xiaoqiang Li,Qunjie Xu,Haimei Liu,Zi-Feng Ma
Na 4 Fe 3 (PO 4 ) 2 P 2 O 7 is considered to be a practical cathode material due to the wide source and low price of raw materials. However, the inherent isolation properties of the PO 4 3− group result in low electronic conductivity and, subsequently, a low discharge capacity and poor cycling stability. Herein, polyvinylpyrrolidone assisted electrospinning method is used to synthesize Na 4 Fe 3 (PO 4 ) 2 P 2 O 7 nanoparticles embedded in carbon nanoribbons . The network structure of active materials wrapped in crosslinked carbon nanoribbons not only enables the ultra-fast transfer of electrons on the three-dimensional “highway” between the nanoparticles but also inhibits the aggregation of nanoparticles. These nanoribbons exhibit remarkable electrochemical performance, resulting from their exceptional electronic and ionic conductivity : high capacity of 128.6 mAh g −1 at 0.1C (1 C = 128.9 mAh g −1 ), extra-high rate capability (61.2 mAh g −1 at 50 C), and ultra-long cycle (72% capacity retention after 5000 cycles at 50 C). Meanwhile, Na 4 Fe 3 (PO 4 ) 2 P 2 O 7 nanoribbon also shows excellent low temperature properties. At −15 °C, the nanoribbon delivers 84.5 mAh g −1 of discharge capacity at 0.05C and displays long-term cycle performance (80.8% capacity retention after 700 cycles at 0.5C). Therefore, the Na 4 Fe 3 (PO 4 ) 2 P 2 O 7 nanoribbon with excellent electrochemical performance can be considered an attractive cathode electrode for the commercialization of sodium-ion battery.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）