原位X射线衍射探究结构相变的研究性实验——以钴酸锂的脱嵌锂相变行为为例RESEARCH EXPERIMENT ON STUDYING THE STRUCTURAL PHASE TRANSITION BY USING IN-SITU X-RAY DIFFRACTION-IN DE-INTERCALATION INDUCED PHASE TRANSITION OF LiCoO2 CATHODE MATERIAL, FOR EXAMPLE
余卿,范昕玥,陈寅,陈越,庄彬,姚胡蓉,黄志高
摘要(Abstract)：
X射线衍射是近代物理学最经典实验之一,开发原位X射线衍射探究材料结构相变过程是一个研究性实验。LiCoO_2作为一种应用广泛的锂离子电池正极材料,其脱嵌锂过程伴随着晶体结构变化,因此钴酸锂是一个很好的应用范例。本文以LiCoO_2在脱锂过程中材料相变行为作为研究对象,利用原位的X射线衍射仪测量分析LiCoO_2作为锂离子电池正极材料在充电过程中两相区的晶粒尺寸变化规律、单胞晶格常数变化趋势以及两相转变过程中相成分比例变化。实验结果不仅证实了脱锂过程中的两相转变,而且表明了原位X射线衍射法可以实时表征锂离子正极材料充放电过程中晶体结构的演化。该研究性实验有助于学生了解X射线衍射应用的研究前沿,不仅可以激发学生的科研兴趣,同时提升了学生的实践能力和创新能力。
关键词(KeyWords)： 原位X射线衍射;研究性实验;锂离子电池;相变;晶体结构
基金项目(Foundation): 国家自然科学基金项目(61574037)
作者(Author): 余卿,范昕玥,陈寅,陈越,庄彬,姚胡蓉,黄志高
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