Enhanced electrochemical performance of MnO nanowire/graphene composite during cycling as the anode material for lithium-ion batteries
Enhanced electrochemical performance of MnO nanowire/graphene composite during cycling as the anode material for lithium-ion batteries
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DOI：
10.1016/j.nanoen.2014.09.012
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发表时间：
2014-11
期刊：
影响因子：
17.6
通讯作者：
Su Zhang;Lingxiang Zhu;Huaihe Song;Xiaohong Chen;Jisheng Zhou
中科院分区：
文献类型：
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作者：
Su Zhang;Lingxiang Zhu;Huaihe Song;Xiaohong Chen;Jisheng Zhou
一般来说，由于电极材料的结构崩溃，锂离子电池（LIB）的容量会在循环过程中逐渐衰减，特别是在大电流密度下。在此，当用作锂离子电池阳极材料时，在长期循环过程中，简单实现的 MnO 纳米线/石墨烯复合材料观察到显着且有利的电化学性能增强。通过高分辨率透射电子显微镜、X射线衍射和傅里叶转移红外光谱表征，MnO纳米线逐渐塌陷为纳米纺锤体和进一步的纳米颗粒，但这些新形成的纳米颗粒仍然稳定地锚定在石墨烯片层上。相应地，MnO纳米线/石墨烯电极的比容量在前几个循环略有下降后表现出显着的增强和耐用寿命。自我增强的原因可归因于 MnO 和石墨烯片之间强烈的相间相互作用。我们的工作为锂离子电池中复合电极的电化学行为提供了新的理解和见解，有助于高性能负极材料的制造。
Generally, the capacity of lithium-ion batteries (LIBs) will fade gradually during cycling especially under large current densities because of the structural collapse of electrode materials. Herein, dramatic and favorable electrochemical performance enhancement was observed in a simply achieved MnO nanowire/graphene composite during long-term cycling when utilized as the anode material for LIBs. Characterized by high-resolution transmission electron microscopy, X-ray diffraction and Fourier-transfer infrared spectroscopy, the MnO nanowires were gradually collapsed to nano-spindles and further nanoparticles but these newly formed nanoparticles are still stably anchored on the graphene lamellas. Correspondingly, the specific capacity of the MnO nanowire/graphene electrode exhibited a significant enhancement with a durable life after a slight decrease in the first several cycles. The reason for the self-enhancement could be ascribed to the strong interphase interaction between MnO and graphene flakes. Our work provides a new understanding and insight for the electrochemical behavior of composite electrodes in LIBs and is helpful for the fabrication of high-performance anode materials.