Growing highly oriented graphite with intrinsic arbitrary curvature will be
the first step in some convenient processes for patterning graphite. While continuous curved crystals of pure graphite will be useful
for cookware and insulation,
applications like filtration and electronics require perforated material.
At least two methods can be suggested for selectively
dendritic, or other curved variants of graphite. The obvious method is to oxidize
(or burn) the material, relying on the
sharp bends to be more reactive than flat graphite.
One possible complication with this method is that oxidative etching can
produce etch pits at defects within seemingly ideal graphite,
as well as at visible kinks.
Etching or dissolving the catalytic or oxidizing particles leaves a pure, perforated
graphite sample. Perforated graphite can be used for filtration or
If the discontinuous film is a suitable oxidation catalyst, like
or some oxidizing species like KNO3, heating the graphite will
cause localized oxidation[1,11].
Metal or other non-volatile substance evaporated onto the sample will accumulate at sites of
high curvature, when the sample is heated. This trick has been used to
locate graphene edges on more conventional graphite samples.
The catalyst is easily removed by acid etching. Hollow
semispherical shells have already been
produced this way.
Initially, a typical curved graphite sample will be attached to
the metal used to catalyze its synthesis. In the case of
free-standing membranes, skip the next step.
Another procedure for selective oxidation of curved graphite is