Synthesis of LiMnPO4 microspheres assembled by plates, wedges and prisms with different crystallographic orientations and their electrochemical performance
Synthesis of LiMnPO4 microspheres assembled by plates, wedges and prisms with different crystallographic orientations and their electrochemical performance
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DOI：
10.1039/c2ce25593f
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发表时间：
2012-09
期刊：
影响因子：
3.1
通讯作者：
Xiao-Liang Pan;Xiao-Liang Pan;Chengyan Xu;L. Zhen
中科院分区：
文献类型：
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作者：
Xiao-Liang Pan;Xiao-Liang Pan;Chengyan Xu;L. Zhen
采用水热法，在200 °C下反应10 h，合成了由不同晶向的板状、楔状和棱柱状组装而成的橄榄石型LiMnPO4微球。以Na2S·9H2O为唯一添加剂，控制了LiMnPO4微球的物相、形貌和晶体取向。采用X射线衍射（XRD）、扫描电镜（SEM）和透射电镜（TEM）对产物进行了表征。基于时间依赖性实验，提出了可能的形成机理。研究了不同组装单元的碳包覆LiMnPO4样品的电化学性能。结果表明，所合成的LiMnPO4微球具有更高的放电容量、更稳定的循环稳定性和更好的倍率性能，这归因于（010）晶面的暴露以及沿[010]方向沿着较小的厚度，使得Li+离子扩散速率快、扩散长度短。
Olivine-structured LiMnPO4 microspheres assembled by plates, wedges and prisms with different crystallographic orientations were synthesized via a facile hydrothermal route at 200 °C for 10 h. Na2S·9H2O was employed as a sole additive for controlling the phase, shape and crystallographic orientation of LiMnPO4 microspheres. The obtained product was characterized by X-ray diffraction (XRD), scanning electron microscope (SEM) and transmission electron microscope (TEM). The possible formation mechanism was proposed based on time-dependent experiments. The electrochemical properties of carbon-coated LiMnPO4 samples with different assembly units were investigated. The synthesized LiMnPO4 microspheres assembled with plates exhibited higher discharge capacity, more stable cycling stability and better rate capability, which were attributed to the exposed (010) facets as well as small thickness along the [010] direction allowing for a fast Li+ ion diffusion rate and short diffusion length.