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Creating Electric Power From Light Using Gold Nanoparticles
cyberfringe writes "Professor of Materials Science Dawn Bonnell and colleagues at the University of Pennsylvania have discovered a way to turn optical radiation into electrical current that could lead to self-powering molecular circuits and efficient data storage. They create surface plasmons that ride the surface of gold nanoparticles on a glass substrate. Surface plasmons were found to increase the efficiency of current production by a factor of four to 20, and with many independent parameters to optimize, enhancement factors could reach into the thousands. 'If the efficiency of the system could be scaled up without any additional, unforeseen limitations, we could conceivably manufacture a 1A, 1V sample the diameter of a human hair and an inch long,' Prof. Bonnell explained. The academic paper was published in the current issue of ACS Nano. (Abstract available for free.) The significance? This may allow the creation of nano-sized circuits that can power themselves through sunlight (or another directed light source). Delivery of power to nanodevices is one of the big challenges in the field."
If the efficiency of the system could be scaled up without any additional, unforeseen limitations
No
It's been a whole month since the last amazing-solar-tech-real-soon-now article. I expect to be entertained by visions of our solar-powered utopian future on at least a weekly basis.
How can I believe you when you tell me what I don't want to hear?
Although it is misleading, I think they meant that the actual structure of the circuit (the leads that run between devices) could actually generate the power, as opposed to having a PV cell somewhere to generate it and then carry it to the load through conventional means. The thought that you can get a watt (1A @ 1V) from a one inch piece of this stuff is really stunning. Considering how many useful things can run on a watt or less, it seems like an absolutely trivial physical package for providing power, the comparable PV cell would be a thousand times larger/heavier, if not more.
Yes
TFA isn't particularly enlightning, but the news is indeed slashdot worthy but raises many questions.
While not currently aimed at solar panel technology
Why not?
their research has uncovered a way to turn optical radiation into electrical current that could lead to self-powering molecular circuits
Battery-free gizmos? It doesn't say, but it seems like the photons wouldn't have to be optical wavelengths. However, how much current does this tech produce? "we could conceivably manufacture a 1A, 1V sample the diameter of a human hair and an inch long"
WOW, that's a lot of power from a tinty surface. 1 amp at one volt is one watt; a device using this tech the size of a phone battery could run an air conditioner if there were any way to keep the thing from melting.
At the end of TFA it links the study.
Free Martian Whores!
They create surface plasmons that ride the surface of gold nanoparticles on a glass substrate.
Boy, does that take me back to my days in the college dorms ... good times.
Having a working knowledge of SPR, I had this idea a couple of years ago and found all kinds of patents on it and a few prototypes already developed... This is not news.
Still, it's a cool concept...
If a man isn't willing to take some risk for his opinions, either his opinions are no good or he's no good
They have their own on-board power generation. Ergo, self-powered.
Any other definition means that nothing was self-powered except possibly and extremely hypothetically the Big Bang.
The enemies of Democracy are
A light of 2.5 KW per square inch is a weapon.
Bruce Perens.
I know Dawn, and I have no idea if the reporter is taking statements out of context or what...
1) This isn't photovoltaic (power generating), and nothing like photovoltaics was demonstrated. Instead, what they showed was that the resistance of a film of gold nanoparticles can be modulated by shining light on it. This isn't overstated in the actual paper, and the explanation they give is good (surface plasmons creating excited states in the polymer between the particles, in the case of red and green light). They used low power diode lasers to see the photoresponse.
2) Scaling of the system: in the paper, they tried a few different sized devices, and say they saw the same response from each of them. This is actually really bad, as you would hope to get more of this kind of response from a larger system.
3) The 1V, 1A comment: Totally crazy. They're seeing less than 1pA at 1V right now, and as they pointed out, are not seeing any scaling behavior, let alone good scaling. It's irresponsible to make (or print) this comment. If doubling the size of the device doesn't change the photoresponse, you should not assume a device 1000 times as big gives 1000 times more response.
Consider the article's quoted claim of a 1A, 1V sample 1 inch long and the diameter of a human hair. This is plainly ridiculous.
Solar radiation intensity in near-Earth space is 1353 W/m^2 (on Earth, under all that atmosphere, it's more like 120 W/m^2). This represents the maximum possible energy input to a solar cell, of whatever design.
A human hair is about 0.001 inch in diameter, so a 1-inch piece held lengthwise covers an area of 0.001 in^2, or 6.45E-7 m^2. At the stated solar irradiance, that area will receive 873 uW of solar irradiance at MOST, in orbit, and rather less on Earth. Unless their solar cell has a 120,000% efficiency, they'll come up rather short on the 1-watt claim (1 V * 1 A = 1 W) in TFA.
I call Fuzzy Math, at least on that particular claim. The rest of their idea may well be good; let's hope the fellow who said this was misquoted, though...
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