Graphene Conductivity: Testing the Resistance

In summary, graphene appears to exhibit negative resistance, which may be useful in creating faster transistors.
  • #1
Matthew Travers
10
0
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?
 
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  • #2
Negative resistance? You're discharging static charge on the polyethylene.
 
  • #3
Thanks for that. So if I connected the sample to Earth first, that would eliminate the faulty reading?
 
  • #4
Sample and meter leads (and probably your hands) to the same ground should take care of it.
 
  • #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
 
  • #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
 

1. What is graphene conductivity?

Graphene conductivity refers to the ability of graphene, a single layer of graphite, to conduct electricity. It is considered the most conductive material known, with a conductivity of over 100,000 times greater than copper.

2. How is graphene conductivity tested?

Graphene conductivity can be tested using various methods, such as four-point probe measurements, scanning tunneling microscopy, and Raman spectroscopy. These techniques involve passing an electrical current through graphene and measuring its resistance.

3. What factors affect graphene conductivity?

The conductivity of graphene is affected by several factors, including its number of layers, defects, and the quality of its crystalline structure. It is also influenced by environmental factors such as temperature and humidity.

4. What are the potential applications of high graphene conductivity?

The high conductivity of graphene makes it a promising material for various applications, such as in electronics, energy storage, and sensors. It could also potentially be used in developing faster and more efficient computer chips and other electronic devices.

5. Can graphene conductivity be improved?

Although graphene has high conductivity, scientists are constantly researching ways to improve it. This includes developing methods to reduce defects and improve the uniformity of graphene layers, ultimately increasing its conductivity. Additionally, combining graphene with other materials can also enhance its conductivity for specific applications.

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