wiredinUSA January 2013

INDEX

3D material for energy storage

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.”

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 2,000m 2 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.

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wiredInUSA - January 2013 wire In - Ja ary 2013

wiredInUSA - January 2013

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