Carbon precipitated onto a curved molten metal surface
routinely resembles origami.
The term "graphite origami" has appeared in the literature, referring to the
large universe of conceivable graphitic materials[4].
The term can be applied more literally to the most common form of curved kish
graphite. Except for the creases and kinks, this appears to be highly
oriented graphite. Thinner deposits are dendritic.
My trademark origami wrinkle was precipitated from iron.
This origami sample has an unusual pale, sinuous rift.
The rift is pale, because thinly covered iron yields secondary
electrons more efficiently than the surrounding pure carbon shell. The
rift probably formed on this sample because the melt was rapidly deforming when it was
suddenly cooled.
Upon closer inspection, several distinct layers
of neatly creased graphite are evident. The discontinuous stacking may
result from the rapid deformation of the melt during the formation of the
creases, or during the precipitation of the graphite itself.
The highest resolution images available so far do not permit us
to confidently identify the creases as twin boundaries, but these graphene
origami images bear a strong resemblance to twin boundary-riddled graphite
samples depicted in older literature[1,5].
EDS of this origami shell confirms it is pure carbon,
Raman spectroscopy identifies graphene of micron-scale
breadth (or better), and XRD confirms the crystallinity
that is evident in the SEM micrograph.
