In what may prove to be a breakthrough in graphene technology, researchers from the University of California, Riverside developed a graphene based transistor based on negative resistance rather then trying to open up a band gap. Those transistors may enable 400Ghz circuits in the future

Negative resistance is the counterintuitive phenomenon in which a current entering a material causes the voltage across it to drop. It was shown before that graphene demonstrates negative resistance in certain circumstances. The new breakthrough is that you can take a regular graphene field-effect transistor (FET) and find the circumstances in which it demonstrates negative resistance. This dip in voltage is used as a kind of switch - to perform logic.

The researchers showed how several graphene FETs combined can be manipulated to produce conventional logic gates. They even designed some circuits (for example a XOR gate that can be made from only 3 GFETs - smaller than silicon based XORs that require at least 8 FETs). They haven't actually produced those circuits yet, though. Read more here.

Researchers from the University of Texas developed high performance (25-Ghz) printed graphene field-effect-transistors (G-FETs) on flexible plastic substrates. They say these are the world's fastest such transistors to date.

The researchers are now working in collaboration with Corning and 3M to demonstrated printed graphene circuits on a larger scale. But don't get too excited yet - they expect that this technology will only be commercialized in 5 or even 10 years. Read more here.

Researchers from Michigan Technological University developed a new 3D Graphene material that can be used to replace platinum used in dye-sensitized solar cells (DSSC). The new material is cheap and easy to make, and using it as an electrode the researcher fabricated a DSSC cell that has an energy efficiency of 7.8% (conventional platinum-electrode based solar cell achieve 8%). Read more here.

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Biogenic Reagents announced that it begun commercial production of graphene-carbon compound based Ultra-Adsorptive Carbon ("UAC") products made from renewable biomass to replace traditional activated carbon products for air and water purification.

Typical Activated Carbon is usually made from coal, but Biogenic's new commercial is made from a wood feedstock - and it has approximately 50% greater adsorption capacity. It will also cost less than coal-based products.

Carbyne is a chain of carbon atoms linked either by alternate triple and single bonds or by consecutive double bonds. This material does not exist in nature (although astronomers believe they have detected its signature in interstellar space) but it can be synthesized.

Researchers have now calculated that this material is about twice as stiff as the stiffest materials known today and is significantly stronger than diamond, carbon nanotubes and graphene. It is also more stable than thought before.