多级结构MoS_(2)/C复合材料的储锂性能

Lithium Storage Properties of Hierarchical MoS_(2)/C Composite Materials

利用二硫化钼和葡萄糖为原料,采用一锅乙醇/水复合溶剂热-后热处理法制备了绣球花状结构MoS_(2)/C复合材料。考查了乙醇/水复合溶剂的合理组成和MoS_(2)/C复合材料中碳的合理含量,分别采用SEM和TEM表征了MoS_(2)/C材料的形貌结构,通过TGA测试和计算了材料中的碳含量。采用循环伏安、恒流充放电和交流阻抗等测试了MoS_(2)/C复合电极的电化学性能。结果表明,MoS_(2)/C复合材料拥有多级花球状结构,缓解了MoS_(2)的团聚,使电极材料的利用率和电化学稳定性显著提高。当V(乙醇)∶V(水)为1∶2,碳含量为50%时,MoS_(2)/C复合电极在200 mA·g^(-1)的电流密度下,充放电循环100次后,可逆容量达到762 mA·h·g^(-1)。

Flower-like MoS_(2)/C composite materials were prepared by one-pot ethanol/water composite solvothermal and postsintering method using MoS_(2) and glucose as raw materials. The reasonable composition of the ethanol/water composite solvent and the reasonable carbon content in the MoS_(2)/C composite material were investigated. The morphology of MoS_(2)/C samples were characterized using SEM and TEM. The carbon content of MoS_(2)/C materials was tested and calculated using TGA. The electrochemical properties of the MoS_(2)/C electrodes were investigated by cyclic voltammetry,galvanostatic charge-discharge measurements and electrochemical impedance spectroscopy. The result indicated that MoS_(2)/C composite materials exhibits hierarchical flower-like structure,which eases the agglomeration of MoS_(2) and increases the utilization and electrochemical stability of the electrode active materials. When Vethanol∶ Vwater= 1 ∶ 2 and the carbon content is 50%,the MoS_(2)/C electrode delivers a reversible capacity of 762 mA·h·g^(-1) at a current density of 200 mA·g^(-1) after 100 cycles.