不同载硅量对Li2FeSiO4/C材料电性能的影响

以多壁纳米碳管和Si(OC2H5)4为原料，采用液相法合成包覆了SiO2的多壁碳纳米管(MWCNTs@SiO2)，通过调节Si(OC2H5)4的加入量，制备出不同载硅量的前驱体MWCNTs@SiO2，并以此种前驱物合成硅酸铁锂Li2FeSiO4/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Li2FeSiO4/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@SiO2前驱体合成的Li2FeSiO4/C材料颗粒大小一致，在0.1C电流密度下循环50圈后获得180 mAh·g－1的稳定放电比容量，具有优良的电化学性能.

Effects of different silicon loading on electrochemical properties of Li2FeSiO4/C materials

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 amount 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 35.72% 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.