Phytic acid assisted synthesis of carbon-coated Na3V2(PO4)3 as a superior cathode material for sodium ion batteries
Phytic acid assisted synthesis of carbon-coated Na3V2(PO4)3 as a superior cathode material for sodium ion batteries
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植酸辅助合成碳包覆的Na3V2(PO4)(3)作为钠离子电池的优质正极材料
DOI：
10.1016/j.mtcomm.2019.100855
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发表时间：
2020-03-01
影响因子：
3.8
通讯作者：
Sun, Daofeng
中科院分区：
文献类型：
--
作者：
Ma, Ping;Kang, Wenpei;Sun, Daofeng
Na3V2(PO4)(3)具有NASICON（钠超离子导体）结构，被认为是一种潜在的钠离子电池正极材料。本文采用植酸可持续磷源合成碳包覆Na3V2(PO4)(3) (Na3V2（PO4)(3)/C-1）纳米颗粒。植酸可以与VO2+离子螯合，原位转化为紧密包覆的碳。因此，Na3V2(PO4)(3)/C-1颗粒的分散性和尺寸分布是理想的，作为sib的正极材料，它将提供增强的电导率和结构稳定性。对于倍率性能，当电流从0.05 A g（-1）增加到5.0 A g（-1）时，容量保持为70.7 mA h g(-)1，容量保持率为73.7%。对于5.0 A g（-1）电流的长期循环，每个循环只有0.0027 mA h g（-1）容量衰减，在5000次循环后容量保持率高达83.9%。恒流间歇滴定技术和电化学阻抗谱证明，钠离子具有较低的电荷转移电阻和较高的扩散系数，具有较高的倍率性能和循环稳定性。
Na3V2(PO4)(3) with NASICON (sodium superionic conductor) structure, has been considered as a potential cathode material for sodium ion batteries (SIBs). Herein, sustainable phosphorus sources of phytic acid is adopted to synthesize carbon coated Na3V2(PO4)(3) (Na3V2(PO4)(3)/C-1) nanoparticles. Phytic acid can chelate with VO2+ ions and in-situ transform into tightly coated carbon. As a result, the dispersivity and size-distribution of Na3V2(PO4)(3)/C-1 particles are ideal, which will provid an enhanced conductivity and structure stability as cathode material for SIBs. For the rate performance, when the current increases from 0.05 A g(-1) to 5.0 A g(-1), a capacity of 70.7 mA h g(-)1 is maintained, corresponding to a capacity retention of 73.7 %. For the long-term cycling at current of 5.0 A g(-1), there is only 0.0027 mA h g(-1) capacity decay per cycle, giving a high capacity retention of 83.9 % after 5000 cycles. The high rate capability and cycling stability is attributed to the lower charge transfer resistance and higher diffusion coefficient of sodium ion, proved by the galvanostatic intermittent titration technique and electrochemical impedance spectroscopy.