Wu Xiaoyu, Wu Huayu, Xie Bin, Wang Rui, Wang Jiaming, Wang Denggui, Shi Qiaofang, Diao Guowang, Chen Ming
School of Chemistry and Chemical Engineering, Yangzhou University, Yangzhou 225002, People's Republic of China.
ACS Nano. 2021 Sep 28;15(9):14125-14136. doi: 10.1021/acsnano.1c04913. Epub 2021 Jul 30.
The rational design of hierarchical hollow nanomaterials is of critical significance in energy storage materials. Herein, dual-wall hollow nanospheres (DWHNS) Sn/MoS@C are constructed by confined growth and interface engineering. The inner hollow spheres of Sn/MoS are formed by atomic soldering MoS nanosheets with liquid Sn at high temperature. The formation mechanism of the hierarchical structure is explored by the morphology evolutions at different temperatures. The DWHNS Sn/MoS@C manifest abundant inner space and high specific surface area, which provides more support sites for Li/Na/K storage and alleviates the volume effect of tin-based electrode materials to a certain extent. The composite material manifests an outstanding specific capacity and satisfactory reversibility of lithium ion batteries (∼931 mAh g at 1 A g after 500 cycles), sodium ion batteries (∼432 mAh g at 1 A g after 400 cycles), and potassium ion batteries (∼226 mAh g at 1 A g after 300 cycles). Additionally, the morphology evolution and mechanism analysis of DWHNS Sn/MoS@C in alkali metal ion batteries are verified by measurement, which confirms the three-in-one hybrid storage mechanism, ., intercalation reaction of carbon shells, conversion reaction of MoS, and alloying reaction of tin.
分级空心纳米材料的合理设计在储能材料中具有至关重要的意义。在此，通过受限生长和界面工程构建了双壁空心纳米球（DWHNS）Sn/MoS@C。Sn/MoS的内部空心球是由MoS纳米片与液态Sn在高温下原子焊接形成的。通过不同温度下的形貌演变探索了分级结构的形成机制。DWHNS Sn/MoS@C具有丰富的内部空间和高比表面积，为锂/钠/钾存储提供了更多的支撑位点，并在一定程度上缓解了锡基电极材料的体积效应。该复合材料在锂离子电池（500次循环后在1 A g下约为931 mAh g）、钠离子电池（400次循环后在1 A g下约为432 mAh g）和钾离子电池（300次循环后在1 A g下约为226 mAh g）中表现出出色的比容量和令人满意的可逆性。此外，通过测量验证了DWHNS Sn/MoS@C在碱金属离子电池中的形貌演变和机理分析，证实了三合一混合存储机制，即碳壳的嵌入反应、MoS的转化反应和锡的合金化反应。
