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Recharge in seconds and efficiently store power for weeks between charges. Added bonus is the cheap and abundant components needed. One of the applications they foresee is to attach such a super-capacitor to the back of solar panels to store the power and discharge this during the night

very nice indeed - is this already at a stage where we should have a closer look at it? what you think? With experience in growing carbon nanostructures, Pint's group decided to try to coat the porous silicon surface with carbon. "We had no idea what would happen," said Pint. "Typically, researchers grow graphene from silicon-carbide materials at temperatures in excess of 1400 degrees Celsius. But at lower temperatures - 600 to 700 degrees Celsius - we certainly didn't expect graphene-like material growth." When the researchers pulled the porous silicon out of the furnace, they found that it had turned from orange to purple or black. When they inspected it under a powerful scanning electron microscope they found that it looked nearly identical to the original material but it was coated by a layer of graphene a few nanometers thick. When the researchers tested the coated material they found that it had chemically stabilized the silicon surface. When they used it to make supercapacitors, they found that the graphene coating improved energy densities by over two orders of magnitude compared to those made from uncoated porous silicon and significantly better than commercial supercapacitors. Transmission electron microscope image of the surface of porous silicon coated with graphene. The coating consists of a thin layer of 5-10 layers of graphene which filled pores with diameters less than 2-3 nanometers and so did not alter the nanoscale architecture of the underlying silicon. (Cary Pint / Vanderbilt) The graphene layer acts as an atomically thin protective coating. Pint and his group argue that this approach isn't limited to graphene. "The ability to engineer surfaces with atomically thin layers of materials combined with the control achieved in designing porous materials opens opportunities for a number of different applications beyond energy storage," he said.

any idea how this works - who wants to have a closer look at it?

Wouldn't it be worth having a closer look?

it's still not clear to me how to get electricity in and out of this thing?

winners of the Future and Emerging Technologies (FET) Flagship competition (informally) announced

Hopefully the money wasted on the brain project will be offset by the gains on graphene... When I heard the proposals presentations on fet11 conference back in 2011, the graphene project was my bet.. Although its motivations were mostly political ("everyone else is working on graphene so if Europe won't do something, we'll soon be far behind"), in contrast to other projects it appeared to have well defined tangible objectives and gave hope of actually delivering something.

We show that the occurrence of superconductivity depends on the adatom in analogy with graphite intercalated compounds (GICs). However, most surprisingly, and contrary to the GIC case, Li covered graphene is superconducting at much higher temperature with respect to Ca covered graphene.

Known technically as a surface plasmon polariton (SPP) wave, the effect will allow the nano-antennas to operate at the low end of the terahertz frequency range, between 0.1 and 10 terahertz - instead of at 150 terahertz With this antenna, we can cut the frequency by two orders of magnitude and cut the power needs by four orders of magnitude," said Jornet. "Using this antenna, we believe the energy-harvesting techniques developed by Dr. Wang would give us enough power to create a communications link between nanomachines." As always, graphene seems to be the answer to anything, but steady progress is being made although one needs to find out first an easy method of generating high quality graphene layers (btw that is also one of the reasons to do the supercapacitor study...)

Well plasmonics is also the solution to everything it seems...

Graphene miracles

Actually since this graphene hype started, being more or less a physics laic, I keep wondering how much of these promised miracles will in fact be delivered? Any chance for an expert's opinion?

Researchers in the US have created the first artificial samples of graphene with electronic properties that can be controlled in a way not possible in the natural form of the material.

Test cell reaches 500Wh/kg and about a 1000 cycles. Graphene is excellent to use as it can handle the thermal expansion during charge cycles which normally destroy the cathodes and thereby degrade performance over time.

study on the environmental effects of graphene. related article http://gizmodo.com/graphene-might-be-way-worse-for-the-environment-than-we-1568823876

The unique structure and properties of graphene and the morphology of the bulk graphene material make it capable of not only absorbing light at various wavelengths but also emitting energetic electrons efficiently enough to drive the bulk material following Newtonian mechanics.

Hard to believe this should actually work, but would be quite a breakthrough indeed. I wonder, since the material should build up a significant electric potential over time, thus, pulling back the ejected electrons. Well, the paper apparently is not peer-reviewed, and I found some rather critical comments in some forums. Let's see if the experiment will be verified by another research team in due course.

isabelle: an option for space baed laser?

The fact that the graphene can emit laser pulses at different wavelengths might be interesting for spectroscopy and laser communications. The tiny dimensions might also help in miniaturization of devices (although apparently a conventional laser is necessary for pumping...). Maybe it would be possible to make very efficient displays with such a technology..?

"Physicists have built a graphene battery that harvests energy from the thermal movement of ions in solution." Can it actually work?

Grown nanoribbons exhibit better conductivity than theory predicts.

Need some Graphene? Use your blender!

Devices made from resonating graphene "drums" could be used as microwave amplifiers and memory chips in quantum computers. So say researchers at the Kavli Institute of Nanoscience at the Delft University of Technology in the Netherlands, who are the first to demonstrate optomechanical coupling between a mechanical resonator and a superconducting microwave cavity.

Both graphene and 3d printing has been around for quite a while, but combined they could provide unique properties of materials, eg in the use of high performance 3d batteries. This paper gives a nice overview of what has been done in the field up to now.

graphene for solar cells ... who wants to have a closer look at it?

Why not but I'm not sure I have the competences/background to do much...

Google Glass 2.0 aka Google Contacts