wiredinUSA January 2013

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wiredInUSA - January 2013
Researchers from Rice University
have developed a graphene and
nanotube hybrid that they believe
could prove to be the best electrode
interface material possible for energy
storage uses.
In appearance, the material is
described as, “forests of carbon
nanotubes that rise quickly from
sheets of graphene to astounding
lengths of up to 120 microns. A house
on an average plot with the same as-
pect ratio would rise into space.” The
vast surface area that this provides
(over 2,000m2 per gram of material) is
the primary factor in creating energy-
storing supercapacitors.
The hybrid is a combination of a
two-dimensional sheet of graphene
with nanotubes, into a seamless
three-dimensional structure.
The seamless bond is created by the
sharing of the electrons of the
adjacent carbon atoms in the two
materials. This essentially fuses them
into one material.
“Many people have tried to attach
nanotubes to a metal electrode and
it’s never gone very well because
they get a little electronic barrier right
at the interface,” explained James
Tour, Rice University chemist, and lead
researcher on the study.
“By growing graphene on metal (in
this case copper) and then growing
nanotubes from the graphene, the
electrical contact between the
nanotubes and the metal electrode
is ohmic. That means electrons see
no difference, because it’s all one
seamless material.”
3D material for
energy storage
18 wire In - Ja ary 2013