  Electrochemical exfoliation is one of the most promising methods for scalable
production of graphene. However, limited understanding of its Raman spectrum as
well as lack of measurement standards for graphene strongly limit its
industrial applications. In this work we show a systematic study of the Raman
spectrum of electrochemically exfoliated graphene, produced using different
electrolytes and different types of solvents in varying amounts. We demonstrate
that no information on the thickness can be extracted from the shape of the 2D
peak as this type of graphene is defective. Furthermore, the number of defects
and the uniformity of the samples strongly depend on the experimental
conditions, including post-processing. Under specific conditions, formation of
short conductive trans-polyacetylene chains has been observed. Our Raman
analysis provides guidance for the community on how to get information on
defects coming from electrolyte, temperature and other experimental conditions,
by making Raman spectroscopy a powerful metrology tool.
