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Physicists Harness the Atomic Motion of Graphene to Generate Clean, Limitless Power
SciTechDaily.com ^ | sOctober 2, 2020 | By University of Arkansas

Posted on 10/02/2020 7:09:57 AM PDT by Red Badger

Researchers build circuit that harnessed the atomic motion of graphene to generate an electrical current that could lead to a chip to replace batteries.

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A team of University of Arkansas physicists has successfully developed a circuit capable of capturing graphene’s thermal motion and converting it into an electrical current.

“An energy-harvesting circuit based on graphene could be incorporated into a chip to provide clean, limitless, low-voltage power for small devices or sensors,” said Paul Thibado, professor of physics and lead researcher in the discovery.

The findings, published in the journal Physical Review E, are proof of a theory the physicists developed at the U of A three years ago that freestanding graphene — a single layer of carbon atoms — ripples and buckles in a way that holds promise for energy harvesting.

The idea of harvesting energy from graphene is controversial because it refutes physicist Richard Feynman’s well-known assertion that the thermal motion of atoms, known as Brownian motion, cannot do work. Thibado’s team found that at room temperature the thermal motion of graphene does in fact induce an alternating current (AC) in a circuit, an achievement thought to be impossible.

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Graphene chip testing — A sample energy-harvesting chip under development. Credit: University of Arkansas

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In the 1950s, physicist Léon Brillouin published a landmark paper refuting the idea that adding a single diode, a one-way electrical gate, to a circuit is the solution to harvesting energy from Brownian motion. Knowing this, Thibado’s group built their circuit with two diodes for converting AC into a direct current (DC). With the diodes in opposition allowing the current to flow both ways, they provide separate paths through the circuit, producing a pulsing DC current that performs work on a load resistor.

Additionally, they discovered that their design increased the amount of power delivered. “We also found that the on-off, switch-like behavior of the diodes actually amplifies the power delivered, rather than reducing it, as previously thought,” said Thibado. “The rate of change in resistance provided by the diodes adds an extra factor to the power.” The team used a relatively new field of physics to prove the diodes increased the circuit’s power. “In proving this power enhancement, we drew from the emergent field of stochastic thermodynamics and extended the nearly century-old, celebrated theory of Nyquist,” said coauthor Pradeep Kumar, associate professor of physics and coauthor.

According to Kumar, the graphene and circuit share a symbiotic relationship. Though the thermal environment is performing work on the load resistor, the graphene and circuit are at the same temperature and heat does not flow between the two.

VIDEO OF PROCESS AT LINK:

Thibado’s energy-harvesting circuit uses the atomic motion of graphene to generate an electrical current that can perform work. Credit: Illustration by Ashley Acord.

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That’s an important distinction, said Thibado, because a temperature difference between the graphene and circuit, in a circuit producing power, would contradict the second law of thermodynamics. “This means that the second law of thermodynamics is not violated, nor is there any need to argue that ‘Maxwell’s Demon’ is separating hot and cold electrons,” Thibado said.

The team also discovered that the relatively slow motion of graphene induces current in the circuit at low frequencies, which is important from a technological perspective because electronics function more efficiently at lower frequencies.

Paul Thibado, professor of physics, holds prototype energy-harvesting chips. Credit: Russell Cothren, University of Arkansas

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“People may think that current flowing in a resistor causes it to heat up, but the Brownian current does not. In fact, if no current was flowing, the resistor would cool down,” Thibado explained. “What we did was reroute the current in the circuit and transform it into something useful.”

The team’s next objective is to determine if the DC current can be stored in a capacitor for later use, a goal that requires miniaturizing the circuit and patterning it on a silicon wafer, or chip. If millions of these tiny circuits could be built on a 1-millimeter by 1-millimeter chip, they could serve as a low-power battery replacement.

Reference: 2 October 2020, Physical Review E. DOI: 10.1103/PhysRevE.102.042101

The University of Arkansas holds several patents pending in the U.S. and international markets on the technology and has licensed it for commercial applications through the university’s Technology Ventures division. Researchers Surendra Singh, University Professor of physics; ; Hugh Churchill, associate professor of physics; and Jeff Dix, assistant professor of engineering, contributed to the work, which was funded by the Chancellor’s Commercialization Fund supported by the Walton Family Charitable Support Foundation.


TOPICS: Business/Economy; History; Science; Society
KEYWORDS: ashleyacord; brownianmotion; carbon; graphene; grapheneoxide; graphyne; hughchurchill; jeffdix; leonbrillouin; maxwellsdemon; paulthibado; pradeepkumar; richardfeynman; robertbrown; russellcothren; science; stringtheory; surendrasingh; uofarkansas; waltonfamilyfndtn
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To: Red Badger

If this is in fact converting heat into electricity, it should also have a refrigerating effect or it would violate the conservation of energy law.


21 posted on 10/02/2020 7:34:27 AM PDT by Telepathic Intruder
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To: Telepathic Intruder

Small amount, I’m sure.................


22 posted on 10/02/2020 7:35:21 AM PDT by Red Badger (Sine Q-Anon.....................very............)
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To: Little Ray

That’s my gut reaction as well.


23 posted on 10/02/2020 7:35:23 AM PDT by Still Thinking (Freedom is NOT a loophole!)
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To: PGR88

Not to sound like a jerk—-but there are a LOT more low energy chips using electricity than there are 3000 pound cars.

Baby steps first.


24 posted on 10/02/2020 7:35:26 AM PDT by Vermont Lt
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To: Red Badger

If it’s Feynman against this guy, I’ll take Feynman.


25 posted on 10/02/2020 7:35:58 AM PDT by Still Thinking (Freedom is NOT a loophole!)
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To: CptnObvious
What is the Frequency?

Apparently Dan Rather knows but call him Kenneth if you do ask him.

26 posted on 10/02/2020 7:37:38 AM PDT by BipolarBob (Cisco Kid was a friend of mine.)
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To: PGR88

Graphene is one of the most expensive materials on the planet. Takes a lot of energy to make it.


27 posted on 10/02/2020 7:39:55 AM PDT by D Rider
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To: Telepathic Intruder
If this is in fact converting heat into electricity, it should also have a refrigerating effect or it would violate the conservation of energy law.

Thank you, that was my thought as well. The voltage (or power) output should vary with ambient temperature. You take power out of the graphene, it should cool slightly. Room temperature raises the temperature of the graphene again, and you can take some more power out of the chip again.

At very low temperatures, there wouldn't be much power to be had out of the graphene chip.

28 posted on 10/02/2020 7:40:55 AM PDT by Yo-Yo ( is the /sarc tag really necessary?)
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To: Still Thinking

Feynman didn’t have the tools and materials to work with the modern physicists have..............


29 posted on 10/02/2020 7:41:12 AM PDT by Red Badger (Sine Q-Anon.....................very............)
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To: Red Badger

Flying Cars are just around the corner!


30 posted on 10/02/2020 7:46:42 AM PDT by xp38
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To: gundog
There's a relatively new building on the Caltech campus that appears to be focused on developing artificial photosynthesis.

If they can crack that nut then turning water into hydrogen and oxygen without the high energy process of electrolysis would be a game changer.

31 posted on 10/02/2020 7:49:00 AM PDT by who_would_fardels_bear
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To: Red Badger
In the linked animation there is a battery in the circuit which isn't described in the article. That leaves the possibility that the graphene isn't producing the energy at all, but rather acting as the oscillator in an AC generation circuit.

Second, the graphene may not be producing any energy at all, but action as an energy capture device from slight variations in room temperature. Imagine on a large scale hooking up the coiled bimetallic element in a thermometer to a generator. As the room heats up it turns one way and as the room cools it turns the other. You would get a little bit of electricity from that.

32 posted on 10/02/2020 7:53:33 AM PDT by KarlInOhio (In 2016 Obama ended America's 220 year tradition of peaceful transfer of power after an election.)
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To: PGR88

But what about moving a 3000 lb car down the road at 60 mph,** in the dead of winter with heater going full blast up a 8% mountain grade?


33 posted on 10/02/2020 7:55:57 AM PDT by PIF (They came for me and mine ... now its your turn)
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To: KarlInOhio
... but rather acting as the oscillator in an AC generation circuit.

From the article:

Thibado’s team found that at room temperature the thermal motion of graphene does in fact induce an alternating current (AC) in a circuit, an achievement thought to be impossible.

34 posted on 10/02/2020 7:56:14 AM PDT by Red Badger (Sine Q-Anon.....................very............)
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To: who_would_fardels_bear

1.23 volts, is required, if memory serves. Not sure what kind of efficiency would be required to make it viable if micro-amperages were employed. I used to wonder about synthetic plants. Graphene might make good “leaves.”


35 posted on 10/02/2020 7:57:56 AM PDT by gundog ( Hail to the Chief, bitches!)
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To: Red Badger

Hope they figure out how to easily make graphene.


36 posted on 10/02/2020 8:00:03 AM PDT by Lurkina.n.Learnin (With age comes wisdom or well practiced ignorance)
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To: PGR88

Unless I learn something else, the best I can see from this might be Internet-of-Things uses.


37 posted on 10/02/2020 8:00:06 AM PDT by Reily
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To: Red Badger
But I'm asking if the battery in the illustration is the real source of power with the graphene merely replacing the capacitor and inductor in an oscillation circuit or if the graphene is the energy source with the diodes acting as the oscillating element as the article implies. That attached video is either a bad example because it shows a battery or it is revealing the man behind the curtain that is really the energy source.

No one would say that the capacitor and inductor in a radio turning circuit are powering the radio.

38 posted on 10/02/2020 8:14:55 AM PDT by KarlInOhio (In 2016 Obama ended America's 220 year tradition of peaceful transfer of power after an election.)
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To: Red Badger

“could be harnessed” or “HAS been harnessed” ?

I COULD date Kate Upton, but HAVE I?


39 posted on 10/02/2020 8:28:20 AM PDT by karnage
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To: PGR88

Powering cheap miniature sensors in a network seems plausible. I am hard put though to imagine other applications.


40 posted on 10/02/2020 8:34:55 AM PDT by Rockingham
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