4.2 Production of Graphene in Molten LiCl
45
Fig. 4.8 Upper panels show SEM micrographs of the graphene nanosheets produced by the molten
salt exfoliation of graphite under a flow of Ar–H 2 . The down-left panels exhibit the XRD diffraction
patterns of a the graphene nanosheets, b powdered graphite material, and c natural graphite flakes.
The inset in the down-left panel reveals the higher magnification of XRD patterns at the two theta
values of 24–29°, around the most intense (002) peak. The down-right panel shows the Raman 2D
peaks of the same materials, reproduced from Ref. [5], copyright 2019, with permission from RSC
Publishing
is around 20 times more than that of the graphite electrode material. This says that
the latter is made up of a much lower-dimensional graphite crystal. Moreover, this
observation can confirm that the graphite flakes in the synthetic graphite material
were haphazardly orientated in the bulk material, as shown in Fig. 4.3. Additionally,
it can be seen that the intensity of the (002) peak in graphene nanosheets is very
much lower than that of the powdered graphite raw material. This result shows that
the graphite cathode was exfoliated to individual/few-layer graphene nanosheets to
a high degree. Nevertheless, a small fraction of less-exfoliated flakes could still exist
in the sample [5].
The down-right panel in Fig. 4.8 compares the 2D Raman band of various carbon
materials: the powdered graphite electrode, graphene nanosheets and natural graphite
45
Fig. 4.8 Upper panels show SEM micrographs of the graphene nanosheets produced by the molten
salt exfoliation of graphite under a flow of Ar–H 2 . The down-left panels exhibit the XRD diffraction
patterns of a the graphene nanosheets, b powdered graphite material, and c natural graphite flakes.
The inset in the down-left panel reveals the higher magnification of XRD patterns at the two theta
values of 24–29°, around the most intense (002) peak. The down-right panel shows the Raman 2D
peaks of the same materials, reproduced from Ref. [5], copyright 2019, with permission from RSC
Publishing
is around 20 times more than that of the graphite electrode material. This says that
the latter is made up of a much lower-dimensional graphite crystal. Moreover, this
observation can confirm that the graphite flakes in the synthetic graphite material
were haphazardly orientated in the bulk material, as shown in Fig. 4.3. Additionally,
it can be seen that the intensity of the (002) peak in graphene nanosheets is very
much lower than that of the powdered graphite raw material. This result shows that
the graphite cathode was exfoliated to individual/few-layer graphene nanosheets to
a high degree. Nevertheless, a small fraction of less-exfoliated flakes could still exist
in the sample [5].
The down-right panel in Fig. 4.8 compares the 2D Raman band of various carbon
materials: the powdered graphite electrode, graphene nanosheets and natural graphite