Scalable Graphene Production

You can imagine the graphene beendeposited on an electro polished copper cylinder and been produced continuouslyat ambient temperature and pressure.  Weare now that close and it looks possible. Tricky of course, but so was flint knapping the last time I checked.

With this, anything can be triedand becomes possible.  How about agraphene laminated wing for a new space shuttle?  Why not a titanium graphene laminate?

We are definitely on the way tomaking the shells used in UFOs or MFEVs. 

The application work on graphenejust as a material has barely begun. Recall that it is unreactive and stronger than diamond and one atomthick.  Producing a continuous ribbon isnow plausible.   Such a ribbon can berolled up continuously to produce a stiff tight cable.  This cable can carry massive power and nicelyreplace our high power cables with something much lighter and stronger.  While we are at it we may as well stuff afiber optic bundle into the core as it is made to add capability.

The same technology producescabling able to handle the needs of a sky tether able to lift goods to orbit.

After that let your imaginationsrun wild.  Rethink everything we maketoday.
Physicists develop scalable method for making graphene

February 25, 2011 by Evan Lerner
Copper-grown graphene circuits. (Photo: Zhengtang Luo)

( -- New research from the University of Pennsylvaniademonstrates a more consistent and cost-effective method for making graphene,the atomic-scale material that has promising applications in a variety offields, and was the subject of the 2010 Nobel Prize in Physics.

As explained in a recently published study, a Penn research team wasable to create high-quality graphene that is just a single atom thick over 95%of its area, using readily available materials andmanufacturing processes that can be scaled up to industrial levels.

“I’m aware of reports of about 90%, so this research is pushing itcloser to the ultimate goal, which is 100%,” said the study’s principalinvestigator, A.T. Charlie Johnson, professor of physics. “We have a vision ofa fully industrial process.”

Other team members on the project included postdoctoral fellowsZhengtang Luo and Brett Goldsmith, graduate students Ye Lu and Luke Somers andundergraduate students Daniel Singer and Matthew Berck, all of Penn’sDepartment of Physics and Astronomy in the School of Arts and Sciences.

The group’s findings were published on Feb. 10 in the journal Chemistryof Materials.

Graphene is a chicken-wire-like lattice of carbon atoms arranged inthin sheets a single atomic layer thick. Its unique physical properties,including unbeatable electrical conductivity, could lead to major advances insolar power, energy storage, computer memory and a host of other technologies.But complicated manufacturing processes and often-unpredictable resultscurrently hamper graphene’s widespread adoption.

Producing graphene at industrial scales isn’t inhibited by the highcost or rarity of natural resources – a small amount of graphene is likely madeevery time a pencil is used – but rather the ability to make meaningfulquantities with consistent thinness.

One of the more promising manufacturing techniques is CVD, or chemicalvapor deposition, which involves blowing methane over thin sheets of metal. Thecarbonatoms in methaneform a thin film of graphene on the metal sheets, but the process must be donein a near vacuum to prevent multiple layers of carbon from accumulating intounusable clumps. 

The Penn team’s research shows that single-layer-thick graphene can bereliably produced at normal pressures if the metal sheets are smooth enough.
“The fact that this is done at atmospheric pressure makes it possibleto produce graphene at a lower cost and in a more flexible way,” Luo, thestudy’s lead author, said.

Whereas other methods involved meticulously preparing custom coppersheets in a costly process, Johnson’s group used commercially available copperfoil in their experiment.
“You could practically buy it at the hardware store,” Johnson said.

Other methods make expensive custom copper sheets in an effort to getthem as smooth as possible; defects in the surface cause the graphene toaccumulate in unpredictable ways. Instead, Johnson’s group “electropolished”their copper foil, a common industrial technique used in finishing silverwareand surgical tools. The polished foil was smooth enough to produce single-layergraphene over 95% of its surface area.

Working with commercially available materials and chemical processesthat are already widely used in manufacturing could lower the bar forcommercial applications.

“The overall production system is simpler, less expensive, and moreflexible” Luo said.

The most important simplification may be the ability to create grapheneat ambient pressures, as it would take some potentially costly steps out offuture graphene assembly lines.

“If you need to work in high vacuum, you need to worry about getting itinto and out of a vacuum chamber without having a leak,” Johnson said. “Ifyou’re working at atmospheric pressure, you can imagine electropolishing thecopper, depositing the graphene ontoit and then moving it along a conveyor belt to another process in the factory.”

Provided by Pennsylvania State University

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