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Joined: 3/24/2012
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Science 335, 1326 (2012);
Maher F. El-Kady, et al. Electrochemical Capacitors
Laser Scribing of High-Performance and Flexible Graphene-Based Electrochemical Capacitors
DOI: 10.1126/science.1216744Although electrochemical capacitors (ECs), also known as supercapacitors or ultracapacitors, charge and discharge faster than batteries, they are still limited by low energy densities and slow rate capabilities. We used a standard LightScribe DVD optical drive to do the direct laser reduction of graphite oxide films to graphene. The produced films are mechanically robust, show high electrical conductivity (1738 siemens per meter) and specific surface area (1520 square meters per gram), and can thus be used directly as EC electrodes without the need for binders or current collectors, as is the case for conventional ECs. Devices made with these electrodes exhibit ultrahigh energy density values in different electrolytes while maintaining the high power density and excellent cycle stability of ECs. Moreover, these ECs maintain excellent electrochemical attributes under high mechanical stress and thus hold promise for high-power, flexible electronics.
Levels equal to power densities of lithium batteries . . . .
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User Rank: Newbie
Joined: 3/24/2012
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Graphene is the electronic material of the future, an atomic monolayer (or few layers) of pure carbon that has amazing electronic abilities, no polllution, very cheap, etc.
I know this application is not YET supported by HP, but in the least it makes an AWESOME science project - - - and in the most hobbyists could create their own massive ultracapacitors for electric cars, etc.
Waiting now for HP to take the lead here and create templates for the most effective capacitor template designs (need mirror image/matching image templates since one graphene layer faces the other layer in assembled product with easily available cell membrane and electrolyte in between).
Obviously HP has whole divisions of electronic engineers that could step in and recommend template designs for hobby lightscribing . . . .
I believe in the full publication I read that the team used some sort of films applied to DVD's and scribed out the graphene on those films, then peeled off the films just like labels.
Graphite oxide is readily converted to graphene through photothermal reduction (high intensity light will cause the oxygen atoms to disassociate). You can see on YouTube videos by this guys professor and also a camera flash method where you would use lithography template.
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