TiO_2-GNs复合材料溶剂热法合成及其电化学性能研究

One-step solvothermal preparation and electrochemical performance of TiO_2/GNs nanocomposites as anode materials for lithium-ion batteries

采用溶剂热法一步合成了TiO2-GNs纳米复合材料。利用XRD、SEM、TEM和BET等测试手段对材料的结构和形貌进行了表征,结果表明,复合材料中TiO2以锐钛矿型纳米颗粒均匀地负载在石墨烯的表面;恒流充放电循环,伏安循环和电化学阻抗等测试结果显示,TiO2-GNs复合材料具有较高的比容量、较好的倍率性能和优异的循环稳定性。在1 C倍率下,复合材料电极循环100圈后其比容量可达到239 m Ah/g;在10 C倍率下,循环100圈后其比容量仍可达150 m Ah/g左右。

The TiO2/GNs Nanocomposites were prepared by a simple one-step solvothermal method. XRD, SEM, TEM and BET analysis were performed to characterize the structures and morphologies of the TiO2/GNs composites. The results show that nanosized anatase TiO2 （about 8-10 nm） is dispersed uniformly on the surface of the GNs, The test results of galvanostatic charge/discharge measurements; CV and EIS reveal the composites exhibit high capacity; better cycle performance and excellent cycle stability. The reversible specific capacity of the nanocomposites electrode is up to 239 mAh/g at 1 C after 100 cycles. The stable discharge specific capacity of TiO2/GNs nanocomposites electrode up to 150 mAh/g was achieved at 10 C and could be maintained after 100 cycles.