长寿命、高倍率超级电容器电极材料的研究——三明治型MoO_3/C插层复合物的原位合成

In Situ Preparation of Sandwich MoO_3/C Hybrid Nanostructures for High-Rate and Ultralong-Life Supercapacitors

利用典型的二维材料α-MoO_3为前驱物,设计并合成了一种特殊的α-MoO_3层和石墨烯插层复合材料.三明治型的MoO_3/C杂化电极材料具有宽的离子扩散通道,低的电荷迁移电阻和稳定的结构,因此具有优异的储能特性.在1 A·g^(-1)的电流密度下,MoO_3/C复合物的比容量为331 F·g^(-1);10 A·g^(-1)时,比容量保持率达到71%.除此,该材料还具有良好的循环稳定性,在1 000~10 000圈的循环过程中比容量基本无衰减.优异的倍率性能使该电极材料具有高功率密度(12.0 k W·kg^(-1))和能量密度(41.2 Wh·kg^(-1)).

This paper presents a design of sandwich MoO_3/C hybrid nanostructure using typical layered α-MoO_3 as a precursor. The sandwich hybrid nanostructure of MoO_3/C has an excellent electrochemical performance, ow-ing to its broad ion diffusion pathway, low charge-transfer resistance, and robust structure at high current densi-ty for long-time cycling. The obtained material is capable of delivering a high specific capacitance of 331 F·g^（-1）at a current density of 1 A·g^（-1）and retained 71%capacitance at 10 A·g^（-1）. In addition, nearly no discharge capac-ity decay between 1 000 and 10 000 continuous charge–discharge cycles is observed at a high current densityof 10 A·g^（-1）. The exceptional rate capability endows the electrode with a high energy density of 41.2 W h·kg^（-1）and a high power density of 12.0 k W·kg^（-1）simultaneously.