NiCo LDH/空心碳管3D复合材料的制备及超级电容器

Fabrication of NiCo LDH/hollow carbon tube 3D composites for supercapacitor application

通过热处理三聚氰胺棉制备得到空心碳管(MC),再通过一步水热法将镍/钴层状双金属氢氧化物(NiCo LDH)负载在MC基底上,成功制备出了高性能的NiCo LDH@MC 3D复合材料,MC基底能够有效分散NiCo LDH纳米片解决了LDH易堆叠的现象,其中空结构也为离子提供了便捷的运输通道,从而获得了高比容量、高倍率性以及具有长循环寿命的超级电容器电极材料。实验结果表明,NiCo LDH@MC在电流密度为0.5 A·g-1下进行恒流充放电测试计算得到的比电容量为1 326.8 F·g-1,在功率密度为2 500 W·kg-1时测得的能量密度为31.53 Wh·kg-1,在电流密度为5 A·g-1时循环1 000次后,电容保持率仍然有83.8%,比电容量仍有880.1 F·g-1。因此,本实验制备的NiCo LDH@MC 3D复合材料是一种非常有前景的超级电容器材料。

In this work,hollow carbon nanotube(MC)was formed by heat treatment of melamine cotton.The nickel/cobalt layered double hydroxide(NiCo LDH)was further grown on the MC via a facile hydrothermal method to fabricate the NiCo LDH@MC 3D composites.The MC substrate could efficiently disperse the NiCo LDH and prevent the aggregation.Meanwhile,the hollow structure also provided a convenient ions transport channel.Moreover,the obtained NiCo LDH@MC 3D composites exhibited a high specific capacitance,excellent rate retentions,and long durability as supercapacitor electrodes.The results show that the specific capacitance of NiCo LDH@MC is 1 326.8 F·g-1 at a current density of 0.5 A·g-1,and the energy density is 31.53 Wh·kg-1 at the power density of 2 500 W·kg-1.After 1 000 cycles at the current density of 5 A·g-1,the capacitance retention rate remains 83.8%,and the specific capacitance is 880.1 F·g-1.Therefore,the prepared NiCo LDH@MC could be used as an advanced supercapacitor electrodes.