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Graphene: Fast, Strong, Cheap, and Impossible To Use
An anonymous reader writes: We keep hearing about the revolutionary properties of graphene, an atom-thick sheet of carbon whose physical characteristics hold a great deal of promise — if we can figure out good ways to produce it and use it. The New Yorker has a lengthy profile of graphene and its discoverer, Andre Geim, as well as one of the physicists leading a big chunk of the bleeding-edge graphene research, James Tour.
Quoting: "[S]cientists are still trying to devise a cost-effective way to produce graphene at scale. Companies like Samsung use a method pioneered at the University of Texas, in which they heat copper foil to eighteen hundred degrees Fahrenheit in a low vacuum, and introduce methane gas, which causes graphene to "grow" as an atom-thick sheet on both sides of the copper—much as frost crystals "grow" on a windowpane. They then use acids to etch away the copper. The resulting graphene is invisible to the naked eye and too fragile to touch with anything but instruments designed for microelectronics. The process is slow, exacting, and too expensive for all but the largest companies to afford. ... Nearly every scientist I spoke with suggested that graphene lends itself especially well to hype."
Quoting: "[S]cientists are still trying to devise a cost-effective way to produce graphene at scale. Companies like Samsung use a method pioneered at the University of Texas, in which they heat copper foil to eighteen hundred degrees Fahrenheit in a low vacuum, and introduce methane gas, which causes graphene to "grow" as an atom-thick sheet on both sides of the copper—much as frost crystals "grow" on a windowpane. They then use acids to etch away the copper. The resulting graphene is invisible to the naked eye and too fragile to touch with anything but instruments designed for microelectronics. The process is slow, exacting, and too expensive for all but the largest companies to afford. ... Nearly every scientist I spoke with suggested that graphene lends itself especially well to hype."
And yet, I read about a team in Cambridge in the UK who have a new low temperature process that can create graphene in industrial quantities. http://cambridgenanosystems.co...
Do you expect the New Yorker to do actual research (or even a google search) before writing an article or something?
That was covered in the summary:
"Nearly every scientist I spoke with suggested that graphene lends itself especially well to hype."
http://www.geoffreylandis.com
I'm a student at Rice, where James Tour teaches. First semester my freshman year, I made the mistake of trying to take Organic Chemistry with James Tour as my professor.
That class proved to me that I was not, in fact, a chemical engineer.
I switched to Computer Science the next year, but it always makes me laugh seeing Prof. Tour's name.
"In the mid 1880s, aluminium metal was exceedingly difficult to produce, which made pure aluminium more valuable than gold.[51] So celebrated was the metal that bars of aluminium were exhibited at the Exposition Universelle of 1855.[52] Napoleon III of France is reputed to held a banquet where the most honored guests were given aluminium utensils, while the others made do with gold." http://en.m.wikipedia.org/wiki...
Graphene in addition to the engineering challenges does have some very fundamental scientific challenges as well.
The most important challenge is its lack of a bandgap meaning that graphene transistors cannot be turned off. That drawback means that while it may have a ~500GHz cutoff frequency on par with silicon and below the InP records it will not modulate current in an energy-efficient way, and while it can create some forms of logic the lack of a bandgap limits its power amplifying frequency to a measly 50GHz, well below the competing technologies. Contrast that with Northrop Grumman's recent 1000GHz amplifier, which is admittedly not a great amplifier since it is run very near its cutoff frequency it has 1dB or less gain per stage, but it works which is still quite impressive.
So far the various methods that can give graphene a bandgap also take away the extremely fast electron transport properties that made graphene so interesting for electronics in the first place. Some of us working on competing technologies wonder why hundreds of millions of dollars have been spent on graphene transistor development without solving the fundamental bandgap problem - of course we just want that money directed to our own research, but some of us try to be realistic about the capabilities of what we are developing ;-)
I'm sure graphene will be useful for some things but so far there are still some fundamental problems that need to be solved before using it for high-speed electronics for wireless applications or digital logic. We'll see how it does.
From the summary: "The process is slow, exacting, and too expensive" and "too fragile to touch". Yet the title says its fast, strong and cheap...
Sig?
It was done when I was freshly born, by a doctor and with anesthesia - which is the *only* acceptable way to to it, btw.!
I disagree. Genital mutilation should be restricted to necessary medical procedures, and people who want it done and can give their consent.