Nature of Bimetallic Oxide Sb2MoO6/rGO Anode for High‐Performance Potassium‐Ion Batteries
Nature of Bimetallic Oxide Sb2MoO6/rGO Anode for High‐Performance Potassium‐Ion Batteries
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DOI：
10.1002/advs.201900904
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发表时间：
2019-06
期刊：
影响因子：
15.1
通讯作者：
Jue Wang;Bin Wang;Zhaomeng Liu;Ling Fan;Qingfeng Zhang;H. Ding;Longlu Wang;Hongguan Yang;
中科院分区：
文献类型：
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作者：
Jue Wang;Bin Wang;Zhaomeng Liu;Ling Fan;Qingfeng Zhang;H. Ding;Longlu Wang;Hongguan Yang;
钾离子电池（KIB）是锂离子电池最有吸引力的替代品之一，考虑到与锂相比，钾资源供应更充足、成本更低，在大型储能设备中尤其有吸引力。为了获得更具竞争力的KIB，有必要寻找高性能的负极材料。在此研究中，存在还原氧化石墨烯的双金属氧化物Sb2MoO6被报道为KIB的高性能负极材料，在100 mA g−1下实现高达402 mAh g−1的放电容量，在200 mA g−1下实现高达381 mAh g−1的放电容量，并在500 mA电流密度下循环100次后保留247 mAh g−1的容量g−1。同时，通过电化学表征、原位X射线衍射、透射电子显微镜和密度泛函理论计算，对该材料的钾化/脱钾机理进行了深入探讨，成功揭示了高性能阳极的本质以及Sb2MoO6中Sb和Mo的功能。更重要的是，成功识别了Sb2MoO6的相发展和键断裂序列，这对于KIBs金属氧化物基电极材料的基础研究具有重要意义。
Potassium‐ion batteries (KIBs) are one of the most appealing alternatives to lithium‐ion batteries, particularly attractive in large‐scale energy storage devices considering the more sufficient and lower cost supply of potassium resources in comparison with lithium. To achieve more competitive KIBs, it is necessary to search for anode materials with a high performance. Herein, the bimetallic oxide Sb2MoO6, with the presence of reduced graphene oxide, is reported as a high‐performance anode material for KIBs in this study, achieving discharge capacities as high as 402 mAh g−1 at 100 mA g−1 and 381 mAh g−1 at 200 mA g−1, and reserving a capacity of 247 mAh g−1 after 100 cycles at a current density of 500 mA g−1. Meanwhile, the potassiation/depotassiation mechanism of this material is probed in‐depth through the electrochemical characterization, operando X‐ray diffraction, transmission electron microscope, and density functional theory calculation, successfully unraveling the nature of the high‐performance anode and the functions of Sb and Mo in Sb2MoO6. More importantly, the phase development and bond breaking sequence of Sb2MoO6 are successfully identified, which is meaningful for the fundamental study of metal‐oxide based electrode materials for KIBs.