不同载硅量对Li_2FeSiO_4/C材料电性能的影响  

Effects of different silicon loading on electrochemical properties of Li_2FeSiO_4/C materials

作　　者：伍雪梅 马晓玲[1] 吴小珍 张友祥[2] 

机构地区：[1]湖北第二师范学院化学与生命科学学院,武汉430205 [2]武汉大学化学与分子科学学院,武汉430073

出　　处：《华中师范大学学报（自然科学版）》2017年第5期632-637,共6页Journal of Central China Normal University：Natural Sciences

基　　金：湖北省自然科学基金项目(2016CFB693);武汉市青年科技晨光计划项目(2017050304010274)

摘　　要：以多壁纳米碳管和Si(OC_2H_5)_4为原料,采用液相法合成包覆了SiO2的多壁碳纳米管(MWCNTs@SiO_2),通过调节Si(OC_2H_5)_4的加入量,制备出不同载硅量的前驱体MWCNTs@SiO_2,并以此种前驱物合成硅酸铁锂Li_2FeSiO_4/C材料.采用X射线衍射(XRD)、扫描电镜(SEM)、透射电镜(TEM)、恒流充放电对Li_2FeSiO_4/C材料进行了表征及电化学性能测试,实验结果表明载硅量为35.72%的MWCNTs@SiO_2前驱体合成的Li_2FeSiO_4/C材料颗粒大小一致,在0.1C电流密度下循环50圈后获得180mAh·g^(-1)的稳定放电比容量,具有优良的电化学性能.Multi-walled carbon nanotubes coated with SiO2 （MWCNTs@SiO2） were prepared by liquid phase method with carbon nanotubes and Si（OC2H5）4 as raw materials. By adjusting the amount of Si（OC2H5）4, MWCNTs@SiO2 precursors with different a-mount of silica were prepared, from which precursors of lithium iron silicate materials Li2FeSiO4/C were synthesized. By using X ray diffraction （XRD）, scanning electron microscopy （SEM）, transmission electron microscopy （TEM） and constant current charge discharge Li2FeSiO4/C materials were characterized with their electrochemical performance examined. Results showed that particle size of Li2FeSiO4/C materials synthesized from MWCNTs@SiO2 precursor with the silicon loading capacity of 35. 720./00 were consistent, and stable discharge capacity of 180 mAh ·g^-1 was generated by these materials after 50 cycles in the current density of 0. 1 C, which suggesting that these materials possess excellent electrochemical performance.

关 键 词：锂离子电池 LI2FESIO4 电化学性能 

分 类 号：O614.81[理学—无机化学] TM912.9[理学—化学]