【作者】 李振； 张露露； 杨学林； 丁晓凯； 周英贤； 孙华斌；

【Author】 Z.Li;L.L.Zhang;X.L.Yang;X.K.Ding;Y.X.Zhou;H.B.Sun;College of Materials and Chemical Engineering,China Three Gorges University;

【机构】 三峡大学材料与化工学院；

【摘要】 通过溶胶凝胶法成功制备出还原氧化石墨烯（rGO）改性铁掺杂磷酸钒锂复合正极材料Li₃V_1.94Fe_0.06（PO₄）₃/C@rGO。与Li₃V₂（PO₄）₃/C及Li₃V₂（PO₄）₃/C@rGO相比,该复合材料表现出最高的放电容量和最优的循环稳定性:2C下其初始放电容量高达159.9 mAh g^-1,100次循环以后容量保持率为84.4%。该电极材料经小倍率循环后,再在5C下循环1000次后,仍能释放出129.3 mAh g^-1的容量,容量保持率高达91.5%,平均每次循环容量衰减仅0.0085%。Li₃V_1.94Fe_0.06（PO₄）₃/C@rGO复合材料优越的电化学性能可归因于铁掺杂和rGO改性的共同作用,这种双重改性更利于减小材料颗粒尺寸、提高电子电导率和增加锂离子扩散系数。我们相信,rGO改性掺杂材料的方法,对于Li₃V₂（PO₄）₃及其它任何聚阴离子型正极材料来说,都是推动并实现它们在动力锂离子电池中应用的一种有效途径。更多还原

【Abstract】 Reduced graphene oxide（rGO） modified Fe-doped Li₃V₂（PO₄）₃/C cathode materials were successfully prepared by sol-gel method.Compared with Li₃V₂（PO₄）₃/C and rGO-incorporated Li₃V₂（PO₄）₃/C,the rGO-incorporated Li₃V_1.94Fe_0.06（PO₄）₃/C electrode behaves the highest initial capacity of 159.9 mAh g^-1 with a capacity retention ratio of 84.4%after 100 cycles at 2 C.When cycled 1000 times at 5 C,it exhibits a prominent capacity of 129.3 mAh g^-1 with a capacity retention ratio of 91.5%.The superior electrochemical performance of Fe-doped and rGO-incorporated Li₃V₂（PO₄）₃ can be contributed to the reduced particle size,the improved electronic conductivity,and the increased Li-ion diffusion coefficient.We believe that this novel co-modification with doping and rGO-incorporating is an efficient way for Li₃V₂（PO₄）₃ and other polyanion cathode materials to promote and realize their application in lithium ion battery.更多还原