(1. 中南大學 材料科學與工程學院，長沙 410083；
2. 中南大學 有色金屬材料科學與工程教育部重點實驗室，長沙 410083)
摘 要: 為了研究具有α-NaFeO2結(jié)構(gòu)的復雜鈷氧化物原子排列規(guī)律，采用固相反應合成了Li0.5Na0.5CoO2多晶粉末，并利用X射線衍射(XRD)、掃描電子顯微分析(SEM)和透射電子顯微分析(TEM)等檢測手段對其形貌、晶體結(jié)構(gòu)等進行了表征。結(jié)果表明：一般處理狀態(tài)下，Li0.5Na0.5CoO2為片狀，其晶體結(jié)構(gòu)與層狀LiCoO2相似，但在某些處理狀態(tài)下通過TEM觀察到沿[0001]帶軸衍射花樣中出現(xiàn)菱面體晶系中應該消光{10 0}的晶面族。這說明Li0.5Na0.5CoO2的晶體結(jié)構(gòu)已經(jīng)由菱面體結(jié)構(gòu)轉(zhuǎn)變成六方結(jié)構(gòu)。
關(guān)鍵字: Li0.5Na0.5CoO2；電子衍射；晶體結(jié)構(gòu)；合成
（1. School of Materials Science and Engineering, Central South University, Changsha 410083, China？
2. Key Laboratory of Nonferrous Materials Science and Engineering, Ministry of Education,
Central South University, Changsha 410083, China）
Abstract:In order to research the structure of complex cobalt oxide compounds with the similar crystallographic features of α-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 Li0.5Na0.5CoO2 and layered LiCoO2(R M) have similar crystal structures. However, the extinction spots of crystal-plane {10 0} of rhombohedral R m space group in [0001] zone axis is detected in TEM patterns, which indicates that the crystal structure of Li0.5Na0.5CoO2 has transformed from rhombohedra system to hexagonal system.
Key words: Li0.5Na0.5CoO2; electron diffraction; crystal structure; synthesis
