Bromination of Graphene and Graphite
Abstract
We present a density functional theory study of low density bromination of graphene and graphite, finding significantly different behaviour in these two materials. On graphene we find a new Br2 form where the molecule sits perpendicular to the graphene sheet with an extremely strong molecular dipole. The resultant Br+-Br- has an empty pz-orbital located in the graphene electronic pi-cloud. Bromination opens a small (86meV) band gap and strongly dopes the graphene. In contrast, in graphite we find Br2 is most stable parallel to the carbon layers with a slightly weaker associated charge transfer and no molecular dipole. We identify a minimum stable Br2 concentration in graphite, finding low density bromination to be endothermic. Graphene may be a useful substrate for stabilising normally unstable transient molecular states.
Keywords
Cite
@article{arxiv.1103.3449,
title = {Bromination of Graphene and Graphite},
author = {A. Yaya and C. P. Ewels and I. Suarez-Martinez and Ph. Wagner and S. Lefrant and A. Okotrub and L. Bulusheva and P. R. Briddon},
journal= {arXiv preprint arXiv:1103.3449},
year = {2011}
}