Power from random walk of molecules in graphene sheets.

[DrP]

This IFLS article points to a team that have found that the random walk in the molecules of graphene cause a single sheet of it on a micro scale to flex/snap back and forth from concave to convex from time to time. Put between conducting plates this oscillation causes a trickle charge of power that could be used to power small devices and do away with the need for a replaceable battery. A 10 micron square of graphene sheet produces about 10 micro watts of power continuously apparently. Presumably these could be stacked to produce more.

http://www.iflscience.com/technology/graphene-loophole-could-provide-clean-and-limitless-energy-in-the-future/

I thought it looked pretty cool. I was going to post this in the thread from a couple of years back about graphene sheets on solar panels that can produce electricity in the rain, but it seemed suitably different enough to warrant its own thread. Here is a recap of that one from 2016 if you missed it. http://www.scienceforums.net/topic/99997-newly-discovered-solar-panels-will-generate-energy-from-raindrops/?tab=comments#comment-951523 

 

 

In terms of questions that arise from this ...   I am assuming,, or asking the question of, how the energy used in the oscillations from convex to concave is replenished to the graphene sheet. Thermal conduction of heat energy? Would the sheet cool eventually as it uses energy from the random walk and have this heat replaced with colliding molecules from the surrounding air?

 

[Carrock]

http://www.iflscience.com/technology/graphene-loophole-could-provide-clean-and-limitless-energy-in-the-future/

This appears to be a second order perpetual motion machine.

Going from a promising design to a working model is always the problem.

[DrP]

38 minutes ago, Carrock said:

This appears to be a second order perpetual motion machine.

... it doesn't break any thermodynamic laws though if, as I suggested, any energy used to make the flip (which comes from vibrational energy of the molecular bonds) is replaced by absorbing energy from the surroundings... i.e. KE from the air molecules bumping into it and increasing the vibrational energy of the system.  

 

[Carrock]

On 01/12/2017 at 3:59 PM, DrP said:

... it doesn't break any thermodynamic laws though if, as I suggested, any energy used to make the flip (which comes from vibrational energy of the molecular bonds) is replaced by absorbing energy from the surroundings... i.e. KE from the air molecules bumping into it and increasing the vibrational energy of the system.  

 

You could get even more power out with a heat engine running between ambient temp and the graphene which has been cooled by converting heat to work.

I still haven't seen anything to suggest this isn't a second order perpetual motion machine.

The original reference https://thibado.uark.edu/wp-content/uploads/sites/316/2017/06/PhysRevLett.117.126801.pdf  is a little unclear but seems simply to claim that externally stressed graphene can produce useful power output.