From Stanford University , the first carbon sequestration project that makes energy. I wonder, will Al Gore say the electricity produced by a carbon solar cell is “dirty energy”? Somewhere, off in the distance, I hear Joe Romm’s head exploding.
Stanford scientists build the first all-carbon solar cell
Stanford University scientists have built the first solar cell made entirely of carbon, a promising alternative to the expensive materials used in photovoltaic devices today.
The results are published in the Oct. 31 online edition of the journal ACS Nano.
“Carbon has the potential to deliver high performance at a low cost,” said study senior author Zhenan Bao, a professor of chemical engineering at Stanford. “To the best of our knowledge, this is the first demonstration of a working solar cell that has all of the components made of carbon. This study builds on previous work done in our lab.”
Unlike rigid silicon solar panels that adorn many rooftops, Stanford’s thin film prototype is made of carbon materials that can be coated from solution. “Perhaps in the future we can look at alternative markets where flexible carbon solar cells are coated on the surface of buildings, on windows or on cars to generate electricity,” Bao said.
The coating technique also has the potential to reduce manufacturing costs, said Stanford graduate student Michael Vosgueritchian, co-lead author of the study with postdoctoral researcher Marc Ramuz.
“Processing silicon-based solar cells requires a lot of steps,” Vosgueritchian explained. “But our entire device can be built using simple coating methods that don’t require expensive tools and machines.”
Carbon nanomaterials
The Bao group’s experimental solar cell consists of a photoactive layer, which absorbs sunlight, sandwiched between two electrodes. In a typical thin film solar cell, the electrodes are made of conductive metals and indium tin oxide (ITO). “Materials like indium are scarce and becoming more expensive as the demand for solar cells, touchscreen panels and other electronic devices grows,” Bao said. “Carbon, on the other hand, is low cost and Earth-abundant.”
For the study, Bao and her colleagues replaced the silver and ITO used in conventional electrodes with graphene – sheets of carbon that are one atom thick –and single-walled carbon nanotubes that are 10,000 times narrower than a human hair. “Carbon nanotubes have extraordinary electrical conductivity and light-absorption properties,” Bao said.
For the active layer, the scientists used material made of carbon nanotubes and “buckyballs” – soccer ball-shaped carbon molecules just one nanometer in diameter. The research team recently filed a patent for the entire device.
“Every component in our solar cell, from top to bottom, is made of carbon materials,” Vosgueritchian said. “Other groups have reported making all-carbon solar cells, but they were referring to just the active layer in the middle, not the electrodes.”
One drawback of the all-carbon prototype is that it primarily absorbs near-infrared wavelengths of light, contributing to a laboratory efficiency of less than 1 percent – much lower than commercially available solar cells. “We clearly have a long way to go on efficiency,” Bao said. “But with better materials and better processing techniques, we expect that the efficiency will go up quite dramatically.”
Improving efficiency
The Stanford team is looking at a variety of ways to improve efficiency. “Roughness can short-circuit the device and make it hard to collect the current,” Bao said. “We have to figure out how to make each layer very smooth by stacking the nanomaterials really well.”
The researchers are also experimenting with carbon nanomaterials that can absorb more light in a broader range of wavelengths, including the visible spectrum.
“Materials made of carbon are very robust,” Bao said. “They remain stable in air temperatures of nearly 1,100 degrees Fahrenheit.”
The ability of carbon solar cells to out-perform conventional devices under extreme conditions could overcome the need for greater efficiency, according to Vosgueritchian. “We believe that all-carbon solar cells could be used in extreme environments, such as at high temperatures or at high physical stress,” he said. “But obviously we want the highest efficiency possible and are working on ways to improve our device.”
“Photovoltaics will definitely be a very important source of power that we will tap into in the future,” Bao said. “We have a lot of available sunlight. We’ve got to figure out some way to use this natural resource that is given to us.”
Other authors of the study are Peng Wei of Stanford and Chenggong Wang and Yongli Gao of the University of Rochester Department of Physics and Astronomy. The research was funded by the Global Climate and Energy Project at Stanford and the Air Force Office for Scientific Research.
This article was written by Mark Shwartz of the Precourt Institute for Energy at Stanford University.
Source: http://news.stanford.edu/news/2012/october/carbon-solar-cell-103112.html
Imagine that. Made from the ashes of CAGW.
Interesting piece of technology. However, the one problem for “green energy” won’t be solved with this. It can never be solved. Because, you see, when the sun doesn’t shine this new solar cell is a very efficient, amazing, high tech and very expensive… lawn ornament.
And I’m convinced that any conventional power station vastly outperforms it.
Carbon solar cell – its called a log.
If manufacturers promise to get their carbon from CO2 in the air instead of from coal in the ground, will this pass the green test?
“Perhaps in the future we can look at alternative markets where flexible carbon solar cells are coated on the surface of buildings, on windows or on cars to generate electricity,” Bao said.
Not to mention roof-tiles….
Great, now that they have come up with a green use for it, the price of carbon will skyrocket
I have this nagging question:
If solar panels become EXTREMELY efficient, wouldn’t it be very cold near them?
won’t they trigger an Ice Age due to loss of heat in the atmosphere?
This is very cool materials science. I fail to see how anyone to not see the benefits of this sort of technology if it can be made economically feasible. It’s not going to replace nuclear, coal or oil but it is going to allow off-grid technology, a boon to the third world.
MMM, promising start! Let’s see how far they can run with it.
I use a lot of graphite in microfurnaces. I’m interested to know how their carbon is stable to 1200F when mine disappears at 800F, in air.
This sounds great. It may even live up to the hype but that will only be know in time. And not a short time either. It completely baffles me (and I may be easily baffled), why people are so down on carbon since we ourselves are mostly made of it. Could it be they just don’t like themselves or is it they like themselves way to much and are misanthropic?
“a boon to the third world.”
So long as they only use the lights while the sun is shining.
Basically talking building a better/cheaper solar cell. Until the power can be controlled, same
old problem that prevents solar cells from being something anyone would want polluting the
utility grid. In two words : junk power, worth very little.
I heard carbon nanotubes run several million dollars a pound at present. That will be a bit of a roadblock to commercial-scale deployment.
Now this is a good idea. Nature has been using carbon as a solar energy converter since the beginning of life – next step is to build the whole apparatus with carbon, hydrogen, oxygen …. Satan’s rock indeed – coal would be the cheapest source of abundant C.
Great. I expect Al Gore is already at work on his “clean carbon” prospectus.
Intended to add that C and Si are neighbors in the same group of the periodic table. Makes sense.
“a laboratory efficiency of less than 1 percent ”
Um OK.
Use it as the top coat for tarmac and then you’re talking. After all, tarmac is made predominantly from the same stuff. I’m being half facetious, given the baby steps described but, then again, in the long term I think it will happen one way or another.
Now, if we could only develope the ALL SILICON Human. (See that similarity in bonds, and the ability to homolog all C compounds with Si compounds of the same structure.)
THEN, we’d be able to tolerate -150 F to 300F temperatures. The only problem is you’d need a plasma torche to cook your Si chicken (“Yum taste like transistors Mommy!”)
This must be the nicer kind of Carbon, not the deadly killer poison Carbon man pollutes the atmosphere with, by burning evil wicked diminishing/dwindling/empty/all used up fossil fuels that will absolutely defininitely be all gone by 2020, as forecast by those brilliant genius’s back in the 1970s, I remember the profound claims in the documentaries to this very day! I bet the Arabs are really running scared that their reserves are nearly all gone, the well pumps must be spluttering erratically by now with only 7 years to go! Good job they keep finding more reserves then, but I guess it won’t be Obama helping Brazil develop its massive reserves in the near future! Anyway, nice development boys & girls, keep up the good work 🙂
The Solar Constant is still 1350 Watts per square meter above the atmosphere, equivalent to 6 – 4 kWh per square meter per 24 hours on the ground.
“Alan Watt,
I heard carbon nanotubes run several million dollars a pound at present.”
Thanks Alan, I was going to ask if anyone knew how expensive these are. I remember when ‘bucky-balls’ were first found, they were a few ppm in middle of a lot of amorphous graphite and since then I haven’t heard much about making these compounds more efficiently.
On the matters solar, the SIDC’s October non-smoothed SSN is finishing at the low 50s (53) down from the September’s 61.5, and far down from the last November’s 96.7
http://www.vukcevic.talktalk.net/SSN.htm
Total polar magnetic field is about to reverse, so SC24 max is imminent.
Eyal Porat says:
October 31, 2012 at 10:18 am
“I have this nagging question:
If solar panels become EXTREMELY efficient, wouldn’t it be very cold near them?
won’t they trigger an Ice Age due to loss of heat in the atmosphere?”
Yes, it would get cold. They are endothermic like photosynthesizing plants. No, it wouldn’t trigger an ice age: When the electricity is consumed the heat is released.
A fascinating idea is to use the carbon nanotubes to siphon off IR background radiation which surrounds us day and night with approx 150 W/m^2. On one hand, this would be an electricity supply available even at night, on the other hand, and more interestingly perhaps, it could possibly be used instead of an A/C.