Vertically Aligned Carbon Nanotubes on Carbon Nanofibers: A Hierarchical Three-Dimensional Carbon Nanostructure for High-Energy Flexible Supercapacitors

详细信息    查看全文

• 作者：Yongcai Qiu ; Guizhu Li ; Yuan Hou ; Zhenghui Pan ; Hongfei Li ; Wanfei Li ; Meinan Liu ; Fangmin Ye ; Xiaowei Yang ; Yuegang Zhang
• 刊名：Chemistry of Materials
• 出版年：2015
• 出版时间：February 24, 2015
• 年：2015
• 卷：27
• 期：4
• 页码：1194-1200
• 全文大小：473K
• ISSN：1520-5002

文摘

Hierarchical structures enable high-performance power sources. We report here the preparation of vertically aligned carbon nanotubes directly grown on carbon nanofibers (VACNTs/CNFs) by combining electrospinning with pyrolysis technologies. The structure and morphology of VACNTs/CNFs could be precisely tuned and controlled by adjusting the percentage of reactants. The desired VACNTs/CNFs could not only possess high electric conductivity for efficient charge transport but could also increase surface area for accessing more electrolyte ions. When using an ionic liquid electrolyte, VACNTs/CNFs-based electric double layer (EDL) flexible supercapacitors can deliver a high specific energy of 70.7 Wh/kg at a current density of 0.5 A/g and at 30 掳C, and an ultrahigh-energy density of 98.8 Wh/kg at a current density of 1.0 A/g and at 60 掳C. Even after 20鈥?00 charging/discharging cycles, the EDL capacitor still retains 97.0% of the initial capacitance. The excellent performance highlights the important role of the branched VACNTs in storing and accumulating charge and the CNF backbone in transporting charge, thereby boosting both power density and energy density.