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arXiv · 0908.1778

Hierarchy of Electronic Properties of Chemically Derived and Pristine Graphene Probed by Microwave Imaging

Worasom Kundhikanjana·Keji Lai·Hailiang Wang·Hongjie Dai·Michael A. Kelly·Zhi-xun Shen
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Abstract

Local electrical imaging using microwave impedance microscope is performed on graphene in different modalities, yielding a rich hierarchy of the local conductivity. The low-conductivity graphite oxide and its derivatives show significant electronic inhomogeneity. For the conductive chemical graphene, the residual defects lead to a systematic reduction of the microwave signals. In contrast, the signals on pristine graphene agree well with a lumped-element circuit model. The local impedance information can also be used to verify the electrical contact between overlapped graphene pieces.

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Worasom Kundhikanjana, Keji Lai, Hailiang Wang, Hongjie Dai, Michael A. Kelly, Zhi-xun Shen. 2009-08-12. Hierarchy of Electronic Properties of Chemically Derived and Pristine Graphene Probed by Microwave Imaging. https://doi.org/10.1021/nl901949z

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