Graphene production - CVD

[pete94857]

Homework Statement: Hello,

I was wondering to produce graphene much faster and less cost. The I believe still current CVD method uses sheet of copper for the graphene to form on during the CVD process, then the copper is removed leaving the pure high grade graphene sheets.

My question is could the same CVD process be used but instead of using sheets of copper instead use liquid Mercury, just below the surface of the liquid Mercury a system of tubes to circulate a coolant to maintain a low temperature liquid Mercury.
Relevant Equations: b1 = 2π 3a ( 1, / 3 ) , b2 = 2π 3a ( 1, - / 3 )

Not my equation

Yes it could.

 

[Baluncore]

https://en.wikipedia.org/wiki/Graphene_production_techniques

 

[pete94857]

Interesting, I'm particularly interested in the production of a continuous sheet.

 

[Baluncore]

Interesting, I'm particularly interested in the production of a continuous sheet.

Aren't we all?
It will come down to the velocity of crystal growth, and the size of the film being grown.
What is your application, and how will you manipulate the sheet ?

 

[pete94857]

My intention is to produce graphene wire for use in high efficiency electric motors and generators such as electric vehicles. I imagine it would increase their efficiency at least 10% if not more. Less lose to heat caused by electrical resistance, less material needed because of its increased conductivity and as a material its density is less than that of copper. I was thinking about using graphene powder and forcing it into a sleeve a bit like a sausage making machine then sealing the ends with a bit of graphite rod but I'm unsure if it would be as good as a solid sheet.

The rest I'm still trying to figure out. Unfortunately a lot of information is difficult to source. I'm not university or even college educated but I seek my information through interest and try to learn as I go.

 

[Baluncore]

Graphene will be difficult to handle, as it naturally rolls up, so why not go one better, and use carbon nanotubes?
You can make conductive rope from the right sort of nanotubes.
https://en.wikipedia.org/wiki/Carbon_nanotube#Electrical

 

[pete94857]

Yes I like the idea thanks I'll consider it.

Are the properties the same with regards to how it functions with electricity ?

 

[russ_watters]

I imagine it would increase their efficiency at least 10% if not more. Less lose to heat caused by electrical resistance, less material needed because of its increased conductivity and as a material its density is less than that of copper.

Unfortunately(?) many electric motors are already above 91% efficiency so they don't have 10% left to gain.

 

[pete94857]

I'd be delightfully surprised. And slightly skeptical.

 

[pete94857]

And is the energy reclaim systems also such efficiency on electric vehicles ?

 

[Vanadium 50]

And slightly skeptical.

In typical industrial sizes, the synchronous motor provides an efficient means of converting AC energy to work (electrical efficiency above 95% is normal for larger sizes)

 

[pete94857]

 

[renormalize]

View attachment 347108

Load (units of HP) at peak efficiency) $\neq$ Efficiency (units of percent) at that load

 

[Vanadium 50]

Pete, Pete, Pete. Google is not a substitute for knowing what you are talking about.

Even if you did not make the mistake that @renormalize pointed out, if the average motor's efficiency is well under 95% does not mean that you can't make a 95+% motor. Indeed, it would show that efficiency is not the only factor in the selection of a motor. (Hint: it's not)

 

[Baluncore]

There is a law of diminishing returns. Getting a 5% improvement in motor efficiency is not worth the investment in a new high technology.

Better investments would be in light-weight rechargeable batteries, solar PV, and transmission line technology. Those are the places where advances will change the game.

10 years before graphene gets to motors or motor controllers, it will enter niche applications where it can actually be a game changer.

 

[berkeman]

Thread is now closed. OP has good intentions, but needs to look more closely at the math, IMO.

Thanks for the (usual) great responses.