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Graphene conductivity

  1. Nov 20, 2014 #1
    Hi
    I've made what I think is graphene. I first put the solution on cardboard and then I put some on polyethylene.
    When they had dried, I tested conductivity with a digital multimeter with the scale set on megaohms.
    The cardboard was nonconducting, but the sample on poly to my astonishment showed a negative resistance.
    I touched the 2 probes together and they read zero, touched them back to the poly sample and again got anegative resistance. Since I am confident that thermodynamic laws are fully universal on all scales governing all energy interactions from solar concentrators to theoretical maxwell demons involving measuring quantum states, there has to be a conservative explanation. Is it some sort of capacitive effect?
     
  2. jcsd
  3. Nov 20, 2014 #2

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    Negative resistance? You're discharging static charge on the polyethylene.
     
  4. Nov 20, 2014 #3
    Thanks for that. So if I connected the sample to earth first, that would eliminate the faulty reading?
     
  5. Nov 20, 2014 #4

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    Sample and meter leads (and probably your hands) to the same ground should take care of it.
     
  6. Nov 21, 2014 #5
    Hang on, just caught up to you...earth everything to discharge and then measure after disconnecting earth.
    Will try that and a couple of other ideas like putting foil on the other side of the polyethylene and connecting that to the sample so it acts like a shorted cap. Cheers mate
     
  7. Nov 23, 2014 #6
    What I found was perhaps not electrostatic discharge. Apparently graphene demonstrates negative resistance or negative differential resistance where an increase of current through the material counter intuitively leads to a drop in voltage. Researchers intographene transistors are seeking to exploit the effect as they predict switching speeds over 400Ghz. It certainly explains why I was unable to detect any significqnt electrstatic charge with the hypersensitive e-field meter I have( its not a DMM). Going to look into this effect more and see if I can come up with anymore uses for it.
    I'll keep you posted. Many thanks for the feedback
     
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