功率型锂离子电池负极材料TiO_2/石墨烯的制备及其电化学性能研究

Preparation and Electrochemical Performance of TiO_2/GNs Nanocomposite as Anode Materials for Lithium-Ion Batteries

采用无表面活性剂回流法制备了蜂窝状TiO2/石墨烯(GNs)复合材料.扫描电子显微镜(SEM)及透射电子显微镜(TEM)表征结果表明,TiO2颗粒约5～10 nm,均匀地分散在石墨烯的表面.锂电池测试显示,1C充电容量稳定在240.1 mAh.g-1;30C充电容量为169.5 mAh.g-1;当电流调回1C时,其充电容量仍可完全恢复(241.7 mAh.g-1);10C 300周期循环电极容量保持率为89.8%.

The honeycomb-like porous TiOJgraphenes （TiOJGNs） nanocomposite was prepared by a reflux method. SEM and TEM results showed that nanosized anatase TiO2 （about 5 - 10 nm） were dispersed uniformly on the surface of the GNs. The TiO2/GNs composite showed excellent rate and cycling performance. A stable charge capacity of 169.5 mAh g-1 was obtained at 30C, and can restore to 241.7 mAh g-1 while current went back to 1C. The stable charge capacity of TiOJGNs nanocomposite electrode up to 201.9 mAh g-1 was achieved at 10C in the first cycle,and could be maintained at 181.4 mAh g-1 after 300 cycles.