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A sheet of graphene is a mere atom thick and has low resistance and high mobility making it optimal for both semiconductor and capacitor applications.  (Source: University of Maryland)
Graphene ultracapacitors could double the storage of existing designs thanks to breakthrough

While the continual progress of efficiencies in solar and wind seem to make these technologies ideal candidates to eventually replace fossil fuels further into the future, one key element stands in the way of their adoption.  That element is variability of the power source.  While one solution would be to offset these power sources with continuous power sources such as tidal or geothermal, another option is storage.

Currently, two primary methods exist of storing power for later use -- rechargeable batteries and ultracapacitors (other exotic methods have also been proposed).  Ultracapacitors are a growing, but not widely known field.  Ultracapacitors can be mixed with fuel cells and batteries or used independently to provide power.  While expensive, ultracapacitors have numerous advantages over batteries, including higher power capability, longer life, a wider thermal operating range, lighter, more flexible packaging and lower maintenance.

Now a new breakthrough promises even better ultracapacitors.  A typical capacitor design features two sheets with an electrolyte between them.  Charge is developed and stored on the sheets.  The key to the new research is to use graphene as the capacitor sheet material. 

Graphene is a unique carbon molecule which is a one-atom-thick planar sheet of sp2-bonded carbon atoms densely packed in a honeycomb-like lattice.  The material has exceptional surface area, among other properties.  It also is a great conductor, and thus is being explored as a material for transistors

Rod Ruoff, a University of Texas at Austin mechanical engineering professor and a physical chemist who led the research describes, "Our interest derives from the exceptional properties of these atom-thick and electrically conductive graphene sheets, because in principle all of the surface of this new carbon material can be in contact with the electrolyte.  Graphene's surface area of 2630 m2/gram (almost the area of a football field in about 1/500th of a pound of material) means that a greater number of positive or negative ions in the electrolyte can form a layer on the graphene sheets resulting in exceptional levels of stored charge."

Professor Ruoff and his team used a chemically modified graphene sheet, and several widely used commercial electrolytes.  The resulting capacitor had a charge stored per weight (called "specific capacitance") rivalling the best available traditional ultracapacitors.  And Professor Ruoff is hopeful that the material's storage can be more than doubled with tweaking.  He states, "There are reasons to think that the ability to store electrical charge can be about double that of current commercially used materials. We are working to see if that prediction will be borne out in the laboratory."

His current team consists of graduate student Meryl Stoller and postdoctoral fellows Sungjin Park, Yanwu Zhu and Jinho An, all from the Mechanical Engineering Department and the Texas Materials Institute at the university.

Their impressive findings are reported in the forthcoming Oct. 8 edition of Nano Letters.

The U.S. Department of Energy has said advancing storage technologies is one of the most pressing needs of the renewable resource industry.  Other fields such as electric cars could also benefit from the research.  A graphene ultracapacitor equipped next-generation version of the Chevy Volt could get twice the range on a single charge or cut the battery weight in half.  It could even extend the life of laptop batteries.

Resources and funding for the project were provided by the Texas Nanotechnology Research Superiority Initiative, The University of Texas at Austin and a Korea Research Foundation Grant for fellowship support for Dr. Park.



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RE: Experiment
By Etsp on 9/17/2008 2:44:34 PM , Rating: 2
I'd actually also like a third article chosen by the DT master himself, Kristopher Kubicki Just to make sure there is at least one neutral party involved. :)


RE: Experiment
By Lord 666 on 9/17/2008 3:40:18 PM , Rating: 2
Ideally, Kris would be included as a writer in all three assignments.

Masher topic - all three write
Mick topic - all three write
Kris topic - all three write


RE: Experiment
By masher2 (blog) on 9/17/2008 4:07:26 PM , Rating: 2
That's 9 papers already. I think people would lose interest long before they reached the end.


RE: Experiment
By danrien on 9/17/2008 5:30:51 PM , Rating: 3
I would actually be interested in seeing this all the time. Sort of like Hannity and Colmes, but without the cherry-picked idiot Colmes that Fox picked to beat up (I honestly pictured a Fox executive finding a homeless bum off the street, and telling him to spew unintelligible shit for a job as long as he went by the name 'Colmes').


RE: Experiment
By TSS on 9/17/2008 6:25:18 PM , Rating: 2
on a regular basis, yes, but for once it would be fun to see the results.

which would probably be anything but non-biased objective journalism. however, that would fit perfectly with most if not all other media outlets.


RE: Experiment
By Lord 666 on 9/17/2008 6:32:32 PM , Rating: 3
Done on a limited basis (once a month, maybe just once) there might be some interest if positioned as a "contest."

To be fair, the author names should be ommitted, but due to the distinct writing styles, the author will be easily identifiable.

One open aspect would be how to grade feedback and author responses to such feedback. A factual piece should be able to stand on its own, but in a collaborative Web 2.0 world, author responses to feedback is always a good thing


RE: Experiment
By johnsonx on 9/17/2008 11:10:53 PM , Rating: 3
I would say Kris doesn't need to write for this purpose, but having him pick one topic is a good idea.

Also, spread it out over a few weeks; we don't need 3 pairs of articles all at once.


"Game reviewers fought each other to write the most glowing coverage possible for the powerhouse Sony, MS systems. Reviewers flipped coins to see who would review the Nintendo Wii. The losers got stuck with the job." -- Andy Marken














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