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arXiv · 1009.0059

Two-step splitting the expandable graphite for few-layer graphene

Kaiming Liao·Wangfeng Ding·Yuyuan Qin·Zhaoguo Li·Taishi Chen·Jianguo Wan·Fengqi Song·Min Han·Guanghou Wang·Jianfeng Zhou
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Abstract

Few-layer graphene sheets are prepared by splitting the expanded graphites using a high-power sonication. Atomic-level quantitative scanning transmission electron microscopy (Q-STEM) is employed to carry out the efficient layer statisticsm, enabling global optimization of the experimental conditions. A two-step splitting mechanism is thus revealed, in which the mean layer number was firstly reduced to less than 20 by heating to 1100°C and then tuned to the few-layer region by a 5-minute 104W/litre sonication. Raman spectroscopic analysis confirms the above mechanism and demonstrates that the sheets are largely free of defects and oxides.

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Kaiming Liao, Wangfeng Ding, Yuyuan Qin, Zhaoguo Li, Taishi Chen, Jianguo Wan, Fengqi Song, Min Han, Guanghou Wang, Jianfeng Zhou. 2010-09-01. Two-step splitting the expandable graphite for few-layer graphene. https://arxiv.org/abs/1009.0059

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