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Accidental Discovery of Almost 100% Efficient Solar Technolo

Posted: Tue Oct 21, 2008 4:03 am
by Roger
Researchers at Ohio State University have accidentally discovered a new solar cell material capable of absorbing all of the sun's visible light energy. The material is comprised of a hybrid of plastics, molybdenum and titanium. The team discovered it not only fluoresces (as most solar cells do), but also phosphoresces. Electrons in a phosphorescent state remain at a place where they can be "siphoned off" as electricity over 7 million times longer than those generated in a fluorescent state. This combination of materials also utilizes the entire visible spectrum of light energy, translating into a theoretical potential of almost 100% efficiency. Commercial products are still years away, but this foundational work may well pave the way for a truly renewable form of clean, global energy.


http://www.tgdaily.com/html_tmp/content ... 7-113.html

A complete study of the team's work appears in the current issue of "Proceedings of the National Academy of Sciences" (PNAS).
Bumped into this at daily Kos, didnt follow up to see if its worthy, just doing a hit and run.

Posted: Tue Oct 21, 2008 4:54 am
by MSimon
Doubt they will get to 100%.

You still have the problem of energy spread. ( 400 to 1200 nm [UV to IR] = 3:1 spread on input energy )

Posted: Tue Oct 21, 2008 6:00 pm
by tombo
Is the suggestion here to use this technology to capture the energy of the Bremsstrahlung radiation?
Of course nobody gets 100% efficiency at anything. but...
Efficiencies approaching unity would certainly help the energy balance and make the Bremsstrahlung losses into a more tractable problem.

Do we know its spectrum yet?
(Was that the 400 to 1200 nm you mentioned? I though you meant that for solar spectrum.)

Western Washington University had a project a few years back that used photovoltaics tuned to IR to convert combustion heat to electricity to drive an electric car motor. Of course it was made from some gawdawfuly toxic elements. IIRC it was a II-VI compound semiconductor system.

If this Ti-Mo-Plastic system can be tuned to the IR or the far IR the implications for waste heat recovery are staggering.
I mean: so what that the Magrid coils get hot we just recover the IR at "100%" efficiency with photovoltaics and push it back into the coils.
My TANSTAAFL detector is flashing "red-alert" ... "red-alert" ... "red-alert".


[edit another source says Mo-W-"thienyl rings" not Mo-Ti-plastic]
Here is a better article: http://www.laserfocusworld.com/display_ ... efficientl
They say the material covers whole visible spectrum 300-1000nm not 100% efficiency. This is more believable.
I hate the way journalists misunderstand and twist scientific statements.
Actually they do that to all statements as anyone who has been interviewed can attest.

Posted: Wed Oct 22, 2008 9:30 pm
by gblaze42
http://www.eetimes.com/news/latest/show ... =211300474


another article, seems to clarify some of it.

Posted: Thu Oct 23, 2008 9:49 pm
by tombo
10,000 nm???
10,000 nm is the wavelength peak for 300K
That is ROOM TEMPERATURE
That has GOT to be a misprint.

Posted: Fri Oct 24, 2008 2:21 am
by KitemanSA
tombo wrote:10,000 nm???
10,000 nm is the wavelength peak for 300K
That is ROOM TEMPERATURE
That has GOT to be a misprint.
The link in you prior post states 1000, not 10,000. Which is the mis-print?

Posted: Fri Oct 24, 2008 2:33 am
by Betruger
It was edited since he posted..

Posted: Fri Oct 24, 2008 4:42 am
by tombo
It is still in gblaze's EE Times linked article.
The link I posted Laser Focus graph shows it petering out below 900nm (~3200K).
Their supercomputer technique may turn up more compounds especially if they look for far IR formulas.
It sure would be nice to get it down to temperatures for reasonable materials.
They are probably motivated in that direction as there are many possible applications, so it is a possible technology in the medium term.

Posted: Fri Oct 24, 2008 2:46 pm
by gblaze42
I've been trying to verify the 10,000 nm point without luck, even reading the original PNAS paper doesn't give me enough to confirm or deny.

Reasoning it out, I suppose if the material could absorb three photons at that wave length, it might work. At that energy level a single photon to electron photo-emission wouldn't work.

It's probably best to send Malcolm Chisholm an email to clarify this.

Posted: Fri Oct 24, 2008 8:50 pm
by MSimon
gblaze42 wrote:I've been trying to verify the 10,000 nm point without luck, even reading the original PNAS paper doesn't give me enough to confirm or deny.

Reasoning it out, I suppose if the material could absorb three photons at that wave length, it might work. At that energy level a single photon to electron photo-emission wouldn't work.

It's probably best to send Malcolm Chisholm an email to clarify this.
If 10,000 nm = 300K I hardly see much use for .03 eV electrons.

Posted: Sun Oct 26, 2008 12:42 am
by KitemanSA
I am much more interested in the 10nm side myself. Brem anyone?