Nanowire Templated Semihollow Bicontinuous Graphene Scrolls: Designed Construction, Mechanism, and Enhanced Energy Storage Performance

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• 作者：Mengyu Yan ; Fengchao Wang ; Chunhua Han ; Xinyu Ma ; Xu Xu ; Qinyou An ; Lin Xu ; Chaojiang Niu ; Yunlong Zhao ; Xiaocong Tian ; Ping Hu ; Hengan Wu ; Liqiang Mai
• 刊名：Journal of the American Chemical Society
• 出版年：2013
• 出版时间：December 4, 2013
• 年：2013
• 卷：135
• 期：48
• 页码：18176-18182
• 全文大小：459K
• 年卷期：v.135,no.48(December 4, 2013)
• ISSN：1520-5126

文摘

Graphene scrolls have been widely investigated for applications in electronics, sensors, energy storage, etc. However, graphene scrolls with tens of micrometers in length and with other materials in their cavities have not been obtained. Here nanowire templated semihollow bicontinuous graphene scroll architecture is designed and constructed through 鈥渙riented assembly鈥?and 鈥渟elf-scroll鈥?strategy. These obtained nanowire templated graphene scrolls can achieve over 30 渭m in length with interior cavities between the nanowire and scroll. It is demonstrated through experiments and molecular dynamic simulations that the semihollow bicontinuous structure construction processes depend on the systemic energy, the curvature of nanowires, and the reaction time. Lithium batteries based on V₃O₇ nanowire templated graphene scrolls (VGSs) exhibit an optimal performance with specific capacity of 321 mAh/g at 100 mA/g and 87.3% capacity retention after 400 cycles at 2000 mA/g. The VGS also shows a high conductivity of 1056 S/m and high capacity of 162 mAh/g at a large density of 3000 mA/g with only 5 wt % graphene added which are 27 and 4.5 times as high as those of V₃O₇ nanowires, respectively. A supercapacitor made of MnO₂ nanowire templated graphene scrolls (MGSs) also shows a high capacity of 317 F/g at 1A/g, which is over 1.5 times than that of MnO₂ nanowires without graphene scrolls. These excellent energy storage capacities and cycling performance are attributed to the unique structure of the nanowire templated graphene scroll, which provides continuous electron and ion transfer channels and space for free volume expansion of nanowires during cycling. This strategy and understanding can be used to synthesize other nanowire templated graphene scroll architectures, which can be extended to other fabrication processes and fields.