
For this metal, electricity flows, but not the heat - upen
http://sciencebulletin.org/archives/9788.html
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lend000
Because of the material's uniquely diametric state transitions and properties,
it gives itself naturally to negative feedback (self-regulating systems) --
for example, as a coating in space windows that reflects more radiation as the
temperature increases. Not to mention the regulation of heat/electrical
conductivity which is the primary subject of the article, in which the
material behaves like an exotic semiconductor:

“This material could be used to help stabilize temperature,” said study co-
lead author Fan Yang, a postdoctoral researcher at Berkeley Lab’s Molecular
Foundry, a DOE Office of Science User Facility where some of the research was
done. “By tuning its thermal conductivity, the material can efficiently and
automatically dissipate heat in the hot summer because it will have high
thermal conductivity, but prevent heat loss in the cold winter because of its
low thermal conductivity at lower temperatures.”

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raziel2701
I don't think this would work for coatings. The dimension and geometry of the
material matter a lot and this is evidenced by the fact that they know that
VO2 has normal behavior in polycrystalline thin-films. The VO2 they studied is
single crystal and shaped into a nanobeam, meaning that already by geometry
there's a huge shape anisotropy that I'm sure influences the properties. The
beam is essentially suspended as well so it's relatively free of strain.
Honestly I don't think this is going to leave the lab, you're not gonna find
this behavior in bulk, only in nanoscale constructions.

Also the title of this submission is wrong, heat does flow, just at a lesser
magnitude than expected from the Wiedemann-Franz law.

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Iv
That... is the great breakthrough that many people were waiting for in
thermoelectric generation.

Tell me it can be easily manufactured and we have a winner. This has the
potential of making solid state thermal plants, where no moving parts would be
required to transform heat into electricity.

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2sk21
Would it be possible to use such a thermo-electric generator as a heat sink
for a chip?

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Iv
Depends what you mean. If you want to use it for power generation then you can
but it is probably a bad idea: it gives resistance to the heat flow.

However, the thermoelectric effect is used by overclockers but on reverse :
they consume energy to move heat from the CPU to a radiator. It is called a
Peltier cell.

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srean
It might interesting to note that diamonds work the other way round, fantastic
insulators of electricity but good conductors of heat.

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Geee
Ceramics too.

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planteen
I used to have to work with transistors backed with BeO (beryllium oxide)
ceramic. A very scary material, inhaling the dust once can cause a lung
condition for life. It is second behind diamond in terms of electrical
insulator, thermal conductor.

[https://en.wikipedia.org/wiki/Beryllium_oxide](https://en.wikipedia.org/wiki/Beryllium_oxide)

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jakeogh
link: [http://newscenter.lbl.gov/2017/01/26/electricity-not-heat-
fl...](http://newscenter.lbl.gov/2017/01/26/electricity-not-heat-flows-in-
vanadium-dioxide/)

I wish they included some more numbers. The paper is paywalled:
[http://newscenter.lbl.gov/2017/01/26/electricity-not-heat-
fl...](http://newscenter.lbl.gov/2017/01/26/electricity-not-heat-flows-in-
vanadium-dioxide/)

I think Fig 1 on page 3 applies:
[https://arxiv.org/pdf/1601.06246.pdf](https://arxiv.org/pdf/1601.06246.pdf)
so it's 100ohms/cm vs 0.0001ohms/cm for the best example. Still looking for
thermal conductivity.

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XorNot
Those electrical properties sure stood out as being superconductorish.

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elorant
Could this be used in CPUs? And would the cost be affordable?

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poizan42
Why would you want a CPU that can't get rid of its heat?

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scawf
Maybe I misunderstand.. but isn't it allowing electricity to flow without
heating ?

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ranger207
No, the electricity flowing will still generate heat. Flipping bits may not
take a lot of power, but it does take power, and some of that power is
converted into heat regardless of what material you use. Except maybe
superconductors, but I'm not sure.

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msimpson
Given some of the comments here I think it's important to note that the
thermal properties of Vanadium are well known and the metal has been used for
years in high-speed steel and alloys, such as Chrome Moly Vanadium, where heat
is the enemy.

This discovery in regard to conductivity could be game changing, but it's not
really a surprise.

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xfactor973
The way they describe the properties of it make it sound like a
superconductor. Am I missing something?

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tempodox
This is great, I wish I had it on my windows now.

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mpatobin
If this could be applied to greenhouses in cold climates that would he
amazing. A glass/polycarbonate coating that lets in the Sun's radiation but
restricts heat from leaving.

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marcosdumay
Current greenhouse insulators already do that, and very well. I don't think
this material would be worth it.

But for electricity generation things are very different.

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suprgeek
This is basically unobtanium [1]

[1][https://www.youtube.com/watch?v=b_HhiU1mOwU](https://www.youtube.com/watch?v=b_HhiU1mOwU)

