Graphene/single-walled carbon nanotube hybrids: one-step catalytic growth and applications for high-rate Li-S batteries.
Graphene/single-walled carbon nanotube hybrids: one-step catalytic growth and applications for high-rate Li-S batteries.
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DOI：
10.1021/nn304037d
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发表时间：
2012-11
期刊：
影响因子：
17.1
通讯作者：
Mengqiang Zhao;Xiaofei Liu;Qiang Zhang;Gui‐Li Tian;Jiaqi Huang;Wancheng Zhu;F. Wei
中科院分区：
文献类型：
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作者：
Mengqiang Zhao;Xiaofei Liu;Qiang Zhang;Gui‐Li Tian;Jiaqi Huang;Wancheng Zhu;F. Wei
理论上提出的石墨烯/单壁碳纳米管（G/SWCNT）混合材料通过共价C-C键将SWCNTs置于石墨烯平面上，有望具有非凡的物理性能和有前景的工程应用。然而，已经制备的G/CNT杂化物与提出的G/ SWCNTs杂化物有很大不同，因为共价C-C键构建得不好，或者杂化物中只有多壁CNTs/碳纳米纤维而不是SWCNTs。在950℃以上的高温下，通过层状双氢氧化物（LDH）催化生长，成功制备了一种新型的G/SWCNT杂化材料。热稳定的铁纳米颗粒和煅烧LDH片的均匀结构是同时催化沉积SWCNTs和石墨烯的必要条件。SWCNTs和cvd生长的石墨烯，以及SWCNTs和石墨烯之间的牢固连接，促进了高导电性通路的构建。两个堆叠的石墨烯层之间和SWCNTs之间的内部空间为硫储存提供了空间。因此,作为获得G / SWCNT-S阴极表现出优良的性能在Li-S电池容量高达650 mAh G(1) 100年以后周期甚至在高电流的5 c这样的小说G / SWCNT混合不仅可以作为原型来揭示G / CNT合成的化学原理也作为一个平台的进一步应用在纳米复合材料领域,多相催化、药物输送、电化学储能,等等。
The theoretically proposed graphene/single-walled carbon nanotube (G/SWCNT) hybrids by placing SWCNTs among graphene planes through covalent C-C bonding are expected to have extraordinary physical properties and promising engineering applications. However, the G/CNT hybrids that have been fabricated differ greatly from the proposed G/SWCNT hybrids because either the covalent C-C bonding is not well constructed or only multiwalled CNTs/carbon nanofibers rather than SWCNTs are available in the hybrids. Herein, a novel G/SWCNT hybrid was successfully fabricated by a facile catalytic growth on layered double hydroxide (LDH) at a high temperature over 950 °C. The thermally stable Fe nanoparticles and the uniform structure of the calcined LDH flakes are essential for the simultaneously catalytic deposition of SWCNTs and graphene. The SWCNTs and the CVD-grown graphene, as well as the robust connection between the SWCNTs and graphene, facilitated the construction of a high electrical conductive pathway. The internal spaces between the two stacked graphene layers and among SWCNTs offer room for sulfur storage. Therefore, the as obtained G/SWCNT-S cathode exhibited excellent performance in Li-S batteries with a capacity as high as 650 mAh g(-1) after 100 cycles even at a high current rate of 5 C. Such a novel G/SWCNT hybrid can serve not only as a prototype to shed light on the chemical principle of G/CNT synthesis but also as a platform for their further applications in the area of nanocomposites, heterogeneous catalysis, drug delivery, electrochemical energy storage, and so on.