New-type K0.7Fe0.5Mn0.5O2 cathode with an expanded and stabilized interlayer structure for high-capacity sodium-ion batteries
New-type K0.7Fe0.5Mn0.5O2 cathode with an expanded and stabilized interlayer structure for high-capacity sodium-ion batteries
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DOI：
10.1016/j.nanoen.2017.03.026
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发表时间：
2017-05
期刊：
影响因子：
17.6
通讯作者：
Xuanpeng Wang;P. Hu;Chaojiang Niu;Jiashen Meng;Xiaoming Xu;Xiujuan Wei;Chunjuan Tang;Wen Luo;Liang Zhou;Qinyou An;L. Mai
中科院分区：
文献类型：
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作者：
Xuanpeng Wang;P. Hu;Chaojiang Niu;Jiashen Meng;Xiaoming Xu;Xiujuan Wei;Chunjuan Tang;Wen Luo;Liang Zhou;Qinyou An;L. Mai
提供兼具高容量和优异循环稳定性的正极是开发用于储能系统的钠离子电池（SIB）的巨大挑战。在这里，我们开发了一种新型钾离子插层层状铁/锰基材料（K0.7Fe0.5Mn0.5O2）。基于先进的原位X射线衍射分析，我们证实K0.7Fe0.5Mn0.5O2在钠化/脱钠过程中可以提供高度可逆的层间距变化和超稳定的骨架结构。因此，K0.7Fe0.5Mn0.5O2 作为 SIB 正极表现出优异的性能，具有高容量和优异的循环稳定性。在 100 mA g−1 时可实现 181 mAh g−1 的高放电容量。值得注意的是，即使以 1000 mA g−1 的高倍率循环，1000 次循环后仍能保持 85% 的初始放电容量。这些结果表明 K0.7Fe0.5Mn0.5O2 是高容量和长寿命 SIB 的有前途的候选材料。此外，这项工作将为高性能储能阴极的开发提供独特的见解。
The delivery of cathodes with both high capacity and excellent cycling stability is a great challenge in the development of sodium-ion batteries (SIBs) for energy storage systems. Here, we exploited a novel potassium-ion-intercalated layered iron/manganese-based material (K0.7Fe0.5Mn0.5O2). On the basis of advancedin situandex situX-ray diffraction analysis, we confirm that K0.7Fe0.5Mn0.5O2can provide highly reversible layer spacing variations and an ultra-stable skeleton structure during the sodiation/desodiation processes. As a result, K0.7Fe0.5Mn0.5O2displays superior performance, with both high capacity and superior cycling stability, as a cathode for SIBs. A high discharge capacity of 181 mAh g−1is achieved at 100 mA g−1. Remarkably, even when cycled at high rate of 1000 mA g−1, 85% of the initial discharge capacity is maintained after 1000 cycles. These results indicate that K0.7Fe0.5Mn0.5O2is a promising candidate for high-capacity and long-life SIBs. Additionally, this work will provide a unique insight into the development of high-performance cathodes for energy storages.