cm401922e_si_001.pdf (2.25 MB)
Deoxygenation of Graphene Oxide: Reduction or Cleaning?
journal contribution
posted on 2015-12-16, 23:35 authored by Helen
R. Thomas, Stephen P. Day, William E. Woodruff, Cristina Vallés, Robert J. Young, Ian A. Kinloch, Gavin W. Morley, John V. Hanna, Neil R. Wilson, Jonathan P. RourkeWe show that the two-component model
of graphene oxide (GO), that
is, composed of highly oxidized carbonaceous debris complexed to oxygen
functionalized graphene sheets, is a generic feature of the synthesis
of GO, independent of oxidant or protocol used. The debris present,
roughly one-third by mass, can be removed by a base wash. A number
of techniques, including solid state NMR, demonstrate that the properties
of the base-washed material are independent of the base used and that
it contains similar functional groups to those present in the debris
but at a lower concentration. Removal of the oxidation debris cleans
the GO, revealing its true monolayer nature and in the process increases
the C/O ratio (i.e., a deoxygenation). By contrast, treating GO with
hydrazine both removes the debris and reduces (both deoxygenations)
the graphene sheets.