【摘要】 采用溶胶-凝胶法制备了氮掺杂的硅酸亚铁锂正极材料.通过X射线衍射（XRD）、扫描电子显微镜（SEM）、X射线光电子能谱（XPS）、充放电测试和交流阻抗测试（EIS）等对材料的结构及电化学性能进行了表征.结果表明,N元素已掺杂到Li₂FeSiO₄材料晶格中,样品具有较小的颗粒尺寸和优异的动力学性能,表现出较好的充放电比容量和倍率特性,首次放电比容量为130 mA·h/g,循环50次后比容量仍可达到124mA·h/g,容量保持率高达95%.更多还原

【Abstract】 N-doped lithium iron silicates（ N-doped Li₂FeSiO₄,N-LFs） was prepared with sol-gel method.X-Ray diffraction,field emission scanning electron microscopy,X-ray photoelectron spectroscopy,galvanostatic charge-discharge and electrochemical impedance spectra were used to investigate the effect of nitrogen doping on the characteristics of Li₂FeSiO₄. The results show that nitrogen does enter the cystal strucutre of Li₂FeSiO₄,resulting in smaller particle size and better kinetic properties,as well as higher specific capacity and rate capability. The doped sample could deliver a specific capacity of 130 mA·h/g in the first discharge and retain 124 mA·h/g after 50 cycles with the retention of 95%.更多还原