常压水解-离子交换法制备TiO2负极材料及其电化学性能研究

Preparation of TiO2 Anode Material by Normal Pressure Hydrolysis-Ion Exchange Method and Its Electrochemical Properties

使用Na盐和K盐通过常压水解-离子交换法合成了“海藻球”状锐钛矿型TiO2。材料表面包裹着超细的纳米TiO2晶须,交错形成三维、相互连接的纳米孔锐钛矿结构。用X射线衍射和扫描电镜对其晶体结构和形貌进行了表征,并对其进行储锂电化学性能测试。材料表现出优异的电化学性能,在100 mA·g-1的电流密度下,首次放电比容量达347 mAh·g-1和242 mAh·g-1,Na盐法制备的TiO2具有较好的倍率性能,在2000 mA·g-1的电流密度下,首次放电比容量分别达168 mAh·g-1,且循环性能良好,循环20圈后仍然保持在153 mAh·g-1。

Anatase TiO2 spheres with algae spherical shape were synthesized using Na salt and K salt by normal pressure hydrolysis-ion exchange method.The surface of the material is covered with ultra-fine nano-TiO2 whiskers,forming three-dimensional,interconnected,nanopore anatase structure.The crystal structure and morphology were characterized by X-ray diffraction(XRD)and scanning electron microscopy(SEM),and the electrochemical performance of lithium storage was tested.The material exhibits excellent electrochemical performance.At a current density of 100 mA·g-1,the first specific discharge capacities of samples synthesized from Na salt and K salt methods are 347 mAh·g-1 and 242 mAh·g-1,respectively.The TiO2 sample prepared by Na salt has better rate performance,it has a high specific capacity of 168 mAh·g-1 at a current density of 2000 mA·g-1,and shows good cycling performance,it still remains at 153 mAh·g-1 after 20 cycles.