Li/Fe摩尔比和表面活性剂浓度对水热合成α-LiFeO_2的影响  

Effects of Li/Fe Molar Ratio and the Concentration of Surface Active Agent on Hydrothermal Synthesis of α-LiFeO_2

作　　者：步明升[1,2] 毕彩丰[1,2] 侯进[1,2] 范玉华[1,2] 王丽[1,2] 

机构地区：[1]中国海洋大学海洋化学理论与工程技术教育部重点实验室,山东青岛266100 [2]中国海洋大学化学化工学院,山东青岛266100

出　　处：《中国海洋大学学报（自然科学版）》2010年第12期121-125,共5页Periodical of Ocean University of China

摘　　要：以α-FeOOH、Li OH.H2O、十六烷基三甲基溴化铵(CTAB)和十二烷基苯磺酸钠(SDBS)为原料,采用水热法合成了α-LiFeO2粉体,利用X射线衍射仪(XRD)、冷场发射扫描电子显微镜(SEM)对粉体的物相和微观形貌进行了表征,研究了不同Li/Fe摩尔比及CTAB浓度对α-LiFeO2物相形成和微观形貌的影响。结果表明:当Li/Fe摩尔比为30∶1,反应温度为210℃,反应时间为6 h时,可得到纯相α-LiFeO2,随着Li/Fe摩尔比的减少,有杂相α-Fe2O3和Li0.5Fe2.5O4生成;表面活性剂CTAB和SDBS对水热合成α-LiFeO2的物相组成没有影响,但对其微观形貌的影响较大。其中,CTAB主要起到了控制粉体粒径大小的作用,而SDBS除了降低粉体粒径外,还影响到了粉体的微观形貌。随着体系SDBS浓度的增大,粉体经历了多面体、层状和类球形3种形貌,并且平均尺寸降至0.3μm左右。α-LiFeO2 was obtained by hydrothermal synthesis involving the reaction between goethite,lithium hydroxide monohydrate,CTAB and SDBS.The structure and morphology of the materials were characterized by XRD and TEM for investigating the effects of different Li/Fe molar ratio,the concentration of CTAB and SDBS.It was shown that pure phase α-LiFeO2 could be successfully synthesized via hydrothermal processing with Li/Fe=30∶1 at 210 ℃ for 6 h.With the decrease of Li/Fe molar ratio,α-Fe2O3 and Li0.5Fe2.5O4 were generated.The CTAB played a major role in controlling the particle size of α-LiFeO2,while the SDBS not only had the ability to reducing the particle size,but also affected the microstructure of the powders.With the increase of SDBS,the samples showed three kinds of morphology,such as polyhedron,layered and spherical,and the average size dropped to about 0.3 μm.

关 键 词：α-LiFeO2 锂离子电池 水热合成 表面活性剂 

分 类 号：O647.2[理学—物理化学]