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A manufacturing process that produces long strips of high-quality graphene

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Re: A manufacturing process that produces long strips of high-quality graphene

#21

Post by AChamarthy »

agumonkey wrote: post #15
AChamarthy wrote: post #7

Many applications of Graphene are already on the market (ex. lighter and stiffer bicycle frames, bicycle tires, sports equipment, electronic inks and paints etc). However, these are based on lower quality Graphene powders or nanoplatelets (essentially a commodity at this point) which are used as an additive to a starting epoxy or resin material. Chemical Vapor Deposition (CVD) is the method used to produce the highes…

How large is the "crowd" in the field (companies, research labs, conferences) ?

EU's biggest research initiative is the Graphene Flagship - https://en.wikipedia.org/wiki/Graphene_Flagship

Major Conferences - Graphene Week, Mobile World Congress (Barcelona + SF), National Graphene Association (inaugural conference was Oct 2017)

Major universities in the US - UT Austin, UPenn, MIT, Stanford, Rice, Berkeley. Lot of activity in Korea, Japan, and China

Companies - Various companies on growth side. Lot of companies doing work in composites and coatings. Various startups looking into supercap, audio, sensor, battery, and water filtration applications

Re: A manufacturing process that produces long strips of high-quality graphene

#22

Post by AChamarthy »

logicallee wrote: post #17
AChamarthy wrote: post #7

Many applications of Graphene are already on the market (ex. lighter and stiffer bicycle frames, bicycle tires, sports equipment, electronic inks and paints etc). However, these are based on lower quality Graphene powders or nanoplatelets (essentially a commodity at this point) which are used as an additive to a starting epoxy or resin material. Chemical Vapor Deposition (CVD) is the method used to produce the highes…

Thanks for making this very informative comment! It was very interesting. Can you give an insider's perspective on graphene's supercapacitor applications, if any? What does it mean in practice? I realize given your disclaimer at the end if there are those kinds of applications you will want to promote them versus listing shortcomings, but if you would at least allude to the shortcomings too I would really appreciate…

In theory, you achieve high power and long charge-discharge lifetimes with graphene-based supercapacitors

The Graphene Flagship is focused on developing methods for combining few-layer graphene and silicon nanoparticles to obtain high performance silicon-graphene anodes.

These new methods need to be cost- effective, scalable and compatible with commercial battery electrode fabrication methods (current bottlenecks). Progress continues to be made in scaling up capacity and size. Flexible graphene supercapacitors were on display at the recent Mobile World Congress

You might've seen this from Samsung - https://news.samsung.com/global/samsung-develops-battery-mat...

Re: A manufacturing process that produces long strips of high-quality graphene

#23

Post by kaennar »

AChamarthy wrote: post #7

Many applications of Graphene are already on the market (ex. lighter and stiffer bicycle frames, bicycle tires, sports equipment, electronic inks and paints etc). However, these are based on lower quality Graphene powders or nanoplatelets (essentially a commodity at this point) which are used as an additive to a starting epoxy or resin material. Chemical Vapor Deposition (CVD) is the method used to produce the highes…

Nordic?

Re: A manufacturing process that produces long strips of high-quality graphene

#24

Post by logicallee »

AChamarthy wrote: post #22
logicallee wrote: post #17

Earlier quoted context omitted.

Thanks for making this very informative comment! It was very interesting. Can you give an insider's perspective on graphene's supercapacitor applications, if any? What does it mean in practice? I realize given your disclaimer at the end if there are those kinds of applications you will want to promote them versus listing shortcomings, but if you would at least allude to the shortcomings too I would really appreciate…

In theory, you achieve high power and long charge-discharge lifetimes with graphene-based supercapacitors The Graphene Flagship is focused on developing methods for combining few-layer graphene and silicon nanoparticles to obtain high performance silicon-graphene anodes. These new methods need to be cost- effective, scalable and compatible with commercial battery electrode fabrication methods (current bottlenecks). P…

Thanks!

Re: A manufacturing process that produces long strips of high-quality graphene

#25

Post by ChuckMcM »

jws wrote: post #16
ChuckMcM wrote: post #13

One of the applications for graphene membranes that I am watching for are large scale desalination plants. It has been shown to work for small membranes and if you had enough surface area you could build a desalinator that was using not much more energy than the energy to pump the water around.

It looks like maybe a factor of 3 or so energy efficiency improvement is available for desalination. Current efficient processes are around 3kWh/m³†. The thermodynamic limit is about 1kWh/m³‡. That can be improved a little if you pump more seawater, there is a tradeoff there. Treatment of fresh water is around 1kWh/m³, so it gets into the ballpark for freshwater treatment, though I presume some of the freshwater trea…

Primarily the concern was "drinking water" for people aka the urban water requirement (which includes drinking, washing, cooking, sanitation, and urban scale irrigation)

I suppose it helps the seasteading picture as well but I haven't really thought much about that.

Mostly if you can disconnect urban water planning from agricultural water planning it allows you to do things differently. Especially when it comes to water transport projects for coastal cities.

Re: A manufacturing process that produces long strips of high-quality graphene

#28

Post by marcosdumay »

NegativeLatency wrote: post #19
chiefalchemist wrote: post #18

How would you dispose of this stuff? I presume it doesn't decompose. Mind you, there's not high volume any time soon. I only curious about lifecycle.

It should burn pretty cleanly (as it's just carbon), but who knows what it would be mixed with in an actual application. Could be mixed with all kinds of plastics and resins that are nasty when burnt.

It should burn with all the side products of most artificial carbon chains (aromatics and poisonous carbon oxides). Those aren't hard to deal with, but don't expect it to burn cleanly.

It should also be hard to burn. It will probably require some water vapor to burn at all, and do it slowly.

Re: A manufacturing process that produces long strips of high-quality graphene

#29

Post by marcosdumay »

DubiousPusher wrote: post #27
fudged71 wrote: post #26

Earlier quoted context omitted.

Not viable, graphene isn't strong enough.

Sources? Googling only returns a bunch of random threads with people insisting it's possible.

In theory any molecule that looks like a graphite layer should be enough. In practice there are plenty of concerns about the stability of the ones that aren't rolled into tubes (and some concern about those later ones too).

The result is, you'll see plenty of calculations telling it's possible. But it is probably not.

Re: A manufacturing process that produces long strips of high-quality graphene

#30

Post by xyzzyz »

NegativeLatency wrote: post #19
chiefalchemist wrote: post #18

How would you dispose of this stuff? I presume it doesn't decompose. Mind you, there's not high volume any time soon. I only curious about lifecycle.

It should burn pretty cleanly (as it's just carbon), but who knows what it would be mixed with in an actual application. Could be mixed with all kinds of plastics and resins that are nasty when burnt.

Graphite is "just carbon" too, but you cannot simply burn it by putting a lit flame to it -- it's simply not hot enough to combust it. To put it in perspective, graphite is frequently used as a crucible to melt aluminum in. Aluminum won't melt in your home fireplace (it's not hot enough), but graphite crucible will easily hold molten aluminum without combusting itself.
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