Article Title

Soluble graphene through edge-selective functionalization

Authors

Zhengzong Sun, Department of Chemistry and Mechanical Engineering and Materials Science and the Smalley Institute for Nanoscale Science and Technology, Rice University, MS 222, 6100 Main Street, Houston, Texas 77005, USA
Shin-ichiro Kohama, Department of Chemistry and Mechanical Engineering and Materials Science and the Smalley Institute for Nanoscale Science and Technology, Rice University, MS 222, 6100 Main Street, Houston, Texas 77005, USA
Zengxing Zhang, Department of Chemistry and Mechanical Engineering and Materials Science and the Smalley Institute for Nanoscale Science and Technology, Rice University, MS 222, 6100 Main Street, Houston, Texas 77005, USA
Jay R. Lomeda, Department of Chemistry and Mechanical Engineering and Materials Science and the Smalley Institute for Nanoscale Science and Technology, Rice University, MS 222, 6100 Main Street, Houston, Texas 77005, USA
James M. Tour, Department of Chemistry and Mechanical Engineering and Materials Science and the Smalley Institute for Nanoscale Science and Technology, Rice University, MS 222, 6100 Main Street, Houston, Texas 77005, USA

Keywords

Edge-selective functionalization, graphene, energy filtered transmission electron microscopy (EFTEM), chemically- assisted exfoliation

Abstract

Thermally expanded graphite was functionalized with 4-bromophenyl addends using the in situ diazonium formation procedure, and after mild sonication treatment in N,N’-dimethylformamide, thin graphene layers were exfoliated from the bulk graphite. These chemically-assisted exfoliated graphene (CEG) sheets had higher solubility than pristine graphene without any stabilizer additive. More than 70% of these soluble flakes had less than 5 layers. Energy filtered transmission electron microscopy (EFTEM) elemental mapping provided evidence of the edge-selective diazonium functionalization with graphene. A majority of the Br signals came from the edges of the CEG indicating that the basal planes were not highly functionalized. The CEG was also characterized by X-ray photoelectron spectroscopy, atomic force microscopy, Raman spectroscopy, and transmission electron microscopy.

Graphical Abstract

DOI

https://doi.org/10.1007/s12274-010-1016-2

Publisher

Tsinghua University Press

Recommended Citation

Zhengzong Sun,Shin-ichiro Kohama,Zengxing Zhang,Jay R. Lomeda,James M. Tour, Soluble graphene through edge-selective functionalization. NanoRes.2010, 3: 117–125