Electrostatic shape control
Surface tension is useful
for producing round graphite shells. Shells of more general shape can be
formed through the application of electrostatic force. This principle
can be proven most conveniently by increasing the bias of the melt during the
usual procedure for synthesizing spherical shells.
This has been tried, producing oblong origami
shells. The schematic, below, shows how melt-grown graphite might be
patterned with arbitrarily distributed asperities.
The technique for electrostatically forming nanoscale
asperities in liquid metal surfaces has already been implemented in the
liquid metal ion sources used in commercial
focused ion milling machines. It may be
possible to pattern graphene films with arrays of
electron field emitters through application of electrostatic force.
Other applications for electric field patterning will be in the formation
of perforated structures like filters, or even