无水层状钠锰氧正极材料的合成及其锂离子嵌入性能  

Preparation and electrochemical Li intercalation performances of anhydrous layered sodium manganese oxides cathode materials

作　　者：杨顺毅[1] 王先友[1] 刘子玲[1] 杨秀康[1] 刘黎[1] 王雁生[1] 王国宝[1] 

机构地区：[1]湘潭大学化学学院,环境友好化学与应用教育部重点实验室,湖南湘潭411105

出　　处：《中南大学学报（自然科学版）》2011年第8期2245-2251,共7页Journal of Central South University:Science and Technology

基　　金：湖南省研究生科研创新项目(CX2009B132);科技部科技计划项目(2009GJD20021);湖南省科技厅重点项目(2009WK2007);湖南省自然科学市州联合基金重点项目(09JJ8001)

摘　　要：分别用醋酸盐溶胶凝胶法和乙醇酸溶胶凝胶法合成无水层状钠锰氧。用热重(TG)、等离子发射光谱(ICP)、X线衍射(XRD)、扫描电镜(SEM)、恒电流充放电测试和循环伏安(CV)等对材料的结构和性能进行研究。研究结果表明:乙醇酸溶胶凝胶法制备的样品α-Na0.65MnO2.13比醋酸盐溶胶凝胶法制备的样品α-Na0.67MnO2.26具有更好的电化学性能。在充放电电流密度为25 mA/g和电压为2.0～4.3 V时,乙醇酸溶胶凝胶法制备的材料α-Na0.65MnO2.13的第2次放电比容量达182 mA.h/g,40次循环后容量保持率达90.6%。Anhydrous layered sodium manganese oxides were synthesized by acetate sol-gel method and glycolic acid sol-gel method,respectively.The structure and performance of as-prepared materials were characterized by thermogravimetric analysis（TG）,inductively coupled plasma（ICP）,X-ray diffractometer（XRD）,scanning electron microscope（SEM）,galvanostatic charge/discharge and cyclic voltammetry（CV）.The results show that the sample α-Na0.65MnO2.13 synthesized by glycolic acid sol-gel method has much better electrochemical performances than that of α-Na0.67MnO2.26 prepared by acetate sol-gel method.Besides,α-Na0.65MnO2.13 exhibits the second discharge capacity of 182 mA·h/g at a current density of 25 mA/g in the cutoff voltage of 2.0-4.3 V,and the capacity retention after 40th cycle is close to 90.6%.

关 键 词：锂离子电池 层状正极材料 钠锰氧化物 比容量 

分 类 号：O646[理学—物理化学]