They could be used to manufacture RFID chips

Aug 6, 2009 07:25 GMT  ·  By
This atomic-force microscope image is colorized to show the topography of a piece of graphene of the type used in the inks; red areas are higher and blue are lower
   This atomic-force microscope image is colorized to show the topography of a piece of graphene of the type used in the inks; red areas are higher and blue are lower

Jessup, MD-based start-up Vorbeck Materials is planning to begin producing the first graphene-based conductive inks later this year to be used for imprinting RFID antennas on substrates. The new material could also play an important part in pushing forward efforts of creating flexible displays, by favoring the production of electrical contacts at the nanoscale. Graphene has sine 2004 been known for its exquisite electrical conductibility, and has been advertised as the best material to start with in constructing a wide array of new electronics, especially at the nanoscale, Technology Review reports.

Vorbeck Materials is off to a good start in the industry, having already received a $5.1-million financing from Stoneham Partners, a private investor, and having signed an agreement with German chemical giant BASF. The company is relying on the low cost associated with producing these inks in its calculations, and hope that further advancements in the technology will bring the costs even further down soon. This would have the direct effect of making the technology more affordable to a wider range of potential customers.

Because pure graphene of the highest quality – to be used for manufacturing transistors – is still extremely difficult to obtain, and cannot be produced at an industrial scale right now, the start-up turned its efforts on producing what it terms “crumpled grapheme,” a less pure form of the bi-dimensional material but still conductive enough to compete with the silver and carbon links currently used in RFID antenna technology.

The process through which graphene is obtained is relatively similar to established ones, but with a twist. The experts start by oxidizing graphite with acid, and then separate the carbon compound into atom-thick layers, which are promptly heated, so as to create carbon dioxide gas. CO2 eventually builds up pressure and forces individual sheets of graphene apart from each other. Afterwards, the sheets are again heated, so as to remove all oxygen groups from their structures. The company also developed an efficient monitoring technique, which allows them to always get the best yield possible.

“The conductivity nears that of pristine graphene, but the sheets are crumpled so they don't stack together again,” explains Princeton university professor of chemical engineering Ilhan Aksay, who is also the main scientific advisor at Vorbeck Materials.