Lu Shiyao, Wu Hu, Xu Siyuan, Wang Yuankun, Zhao Jianyun, Li Yuhan, Abdelkader Amr M, Li Jiao, Wang Wei Alex, Xi Kai, Guo Yuzheng, Ding Shujiang, Gao Guoxin, Kumar Ramachandran Vasant
Xi'an Key Laboratory of Sustainable Energy Materials Chemistry, School of Chemistry, Xi'an Jiaotong University & Shaanxi Quantong Joint Research Institute of New Energy Vehicles Power, Xi'an Jiaotong University, Xi'an, 710049, China.
Department of Chemistry, City University of Hong Kong, Hong Kong, 999077, China.
Small. 2021 Feb;17(8):e2005745. doi: 10.1002/smll.202005745. Epub 2021 Jan 31.
Rechargeable alkali metal-ion batteries (AMIBs) are receiving significant attention owing to their high energy density and low weight. The performance of AMIBs is highly dependent on the electrode materials. It is, therefore, quite crucial to explore suitable electrode materials that can fulfil the future requirements of AMIBs. Herein, a hierarchical hybrid yolk-shell structure of carbon-coated iron selenide microcapsules (FeSe @C-3 MCs) is prepared via facile hydrothermal reaction, carbon-coating, HCl solution etching, and then selenization treatment. When used as the conversion-typed anode materials (CTAMs) for AMIBs, the yolk-shell FeSe @C-3 MCs show advantages. First, the interconnected external carbon shell improves the mechanical strength of electrodes and accelerates ionic migration and electron transmission. Second, the internal electroactive FeSe nanoparticles effectively decrease the extent of volume expansion and avoid pulverization when compared with micro-sized solid FeSe . Third, the yolk-shell structure provides sufficient inner void to ensure electrolyte infiltration and mobilize the surface and near-surface reactions of electroactive FeSe with alkali metal ions. Consequently, the designed yolk-shell FeSe @C-3 MCs demonstrate enhanced electrochemical performance in lithium-ion batteries, sodium-ion batteries, and potassium-ion batteries with high specific capacities, long cyclic stability, and outstanding rate capability, presenting potential application as universal anodes for AMIBs.
可充电碱金属离子电池（AMIBs）因其高能量密度和低重量而备受关注。AMIBs的性能高度依赖于电极材料。因此，探索能够满足AMIBs未来需求的合适电极材料至关重要。在此，通过简便的水热反应、碳包覆、盐酸溶液蚀刻，然后进行硒化处理，制备了碳包覆硒化铁微胶囊（FeSe@C-3 MCs）的分级混合蛋黄壳结构。当用作AMIBs的转换型阳极材料（CTAMs）时，蛋黄壳结构的FeSe@C-3 MCs展现出优势。首先，相互连接的外部碳壳提高了电极的机械强度，并加速了离子迁移和电子传输。其次，与微米级固体FeSe相比，内部的电活性FeSe纳米颗粒有效地降低了体积膨胀程度，避免了粉化。第三，蛋黄壳结构提供了足够的内部空隙，以确保电解质渗透，并促进电活性FeSe与碱金属离子的表面和近表面反应。因此，所设计的蛋黄壳结构FeSe@C-3 MCs在锂离子电池、钠离子电池和钾离子电池中表现出增强的电化学性能，具有高比容量、长循环稳定性和出色的倍率性能，展现出作为AMIBs通用阳极的潜在应用价值。
