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Special semiconductor needed

  1. Oct 11, 2009 #1


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    Hi, I have a super capacitor that is charged at 100,000+V at 0.1uF. Naturally it wants to give of its energy instantaneously in a spark; but im trying to find a compound or semiconductor that can regulate the output of electricity from this capacitor without wasting the majority of the energy as heat.

    I've envisioned a semiconductor that only lets x current through with a source at 100,000+V, but once the cap voltage drops low enough, there wouldn't be enough voltage to flow across the semiconductor. This "wastes" the rest of the energy in the cap which defeats the purpose.

    I'm asking if there is an existing compound or semiconductor that can regulate its conductivity in a wide enough range to make the output voltage low enough at a near constant rate to be useful (~1-200V range).
    A transistor comes to mind, but to my understanding, its range of conductivity is not wide enough to be 'useful'.
  2. jcsd
  3. Oct 11, 2009 #2


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    So, can one take a non conductive polymer and impregnate it with x percent lengths of nano scale ballistic conductors (metallic single wall carbon nano tubes) and achieve partial conductivity but without the loss of a lot of heat? To my understanding, since the electrons can't travel through the polymer the only route to travel through is the carbon nano tubes which are near perfect conductors (hence the ballistic conduction).

    Or, would the electrons traveling through the SWCNT's "collide" with the molecules of the non conductive polymer and create friction thus heat? (although I still dont understand how electricity would be able to flow at all in those areas because it is an open circuit thus no current and no friction).
    I see it like a bolt of lightning where there are many many splits from the main discharge path, but they stop because they dont have a path to ground. Similar to the lengths of CNT's empregnated in the polymer woud act as the ionized air particles in a lightning bolt. The current would only flow through the sections of CNT's that are all touching one another creating a path for the electrons to flow.

    Where the electrons flow through there would be a direct path to the other side of the polymer, there would be incredibly little resistance creating a "single position valve for electrons" without the loss of energy through collisions (heat). the conductivity can vary with the concentration of CNT's as long as the polymer is a homogeneous mixture.
    Am I correct?

    Briefly explained here: http://www.entegris.com/Resources/Images/20257.pdf [Broken]
    Last edited by a moderator: May 4, 2017
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