为了研究具有α-NaFeO 2结构的复杂钴氧化物原子排列规律，采用固相反应合成了Li 0.5 Na 0.5 CoO 2多晶粉末，并利用X射线衍射(XRD)、扫描电子显微分析(SEM)和透射电子显微分析(TEM)等检测手段对其形貌、晶体结构等进行了表征。结果表明：一般处理状态下，Li 0.5 Na 0.5 CoO 2为片状，其晶体结构与层状LiCoO 2相似，但在某些处理状态下通过TEM观察到沿[0001]带轴衍射花样中出现菱面体晶系中应该消光{1010}的晶面族。这说明Li 0.5 Na 0.5 CoO 2的晶体结构已经由菱面体结构转变成六方结构。%In order to research the structure of complex cobalt oxide compounds with the similar crystallographic features ofα-NaFeO2, the solid state reaction was used to prepare the Li0.5Na0.5CoO2, whose crystal structure and morphology were characterized by X-ray diffractometry (XRD), scanning electron microscopy(SEM),transmission electron microscopy (TEM). The results show that, under normal conditions, the platelet-like Li0.5Na0.5CoO2and layered LiCoO2(R3M) have similar crystal structures. However, the extinction spots of crystal-plane {1010} of rhombohedral R3m space group in [0001] zone axis is detected in TEM patterns, which indicates that the crystal structure of Li0.5Na0.5CoO2has transformed from rhombohedra system to hexagonal system.
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