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Graphene Creates Electricity When Struck By Light
MrSeb writes with news out of MIT about another interesting and potentially useful property of graphene. Researchers have known for several years that graphene generates electricity when exposed to sunlight, but incorrectly attributed it to the photovoltaic effect. A new paper shows that the current is actually generated from the much more unusual 'hot-carrier' response. Quoting:
"The material’s electrons, which carry current, are heated by the light, but the lattice of carbon nuclei that forms graphene’s backbone remains cool. It’s this difference in temperature within the material that produces the flow of electricity. ... Such differential heating has been observed before, but only under very special circumstances: either at ultralow temperatures (measured in thousandths of a degree above absolute zero), or when materials are blasted with intense energy from a high-power laser. This response in graphene, by contrast, occurs across a broad range of temperatures all the way up to room temperature, and with light no more intense than ordinary sunlight."
It will take more work to determine what new applications are reasonable from an efficiency perspective, but it does broaden graphene's already-impressive capabilities.
This has absolutely nothing to do with light, and instead has absolutely incredible implications for power generation. Graphene geothermal probes for more efficiency, graphene cooling tubes for maximum gas/oil/coal electric power generation, nuclear power (bonus: extra radiation protection)... Hell, strap graphene to just about any process that involves waste heat and get power for "free!"
are you asking why people might find it difficult to put big oil/coal companies out of business?
I don't think going out of business is in the cards for them. They'll just switch to whatever technology is most profitable. BP didn't change their slogan to "Beyond Petroleum" for no reason.
Sometimes the light at the end of the tunnel is the headlight of an oncoming train.
Producing in the labs vs producing in a manufacturing setting is worlds apart simply. Depending on the technology, there are lots of reasons why some takes decades to reach the market while others never reach it at all.
These include:
1) economic viability (the technology costs too much)
2) production viability (difficult if not impossible to produce at a large scale) which may require manufacturing technology to be developed as well or simply is impossible due to it's nature
3) technological issues (which the technology shows great interests but requires dealing with issues that must be addressed first before it can be used)
In this case, graphene, while many breakthroughs have been made with the materials, it still requires much more research as there are alot of issues to deal with and things we still don't understand about it.
The largest problem I have had with coming around on the energy / global climate debate is that these horrible dire predictions are always accompanied by the most ineffectual proposals to mitigate the effects. No one is really coming out and saying straight up there is no solution we just must reduce consumption in a way that is incompatible with current society. Either they are wrong about the magnitude of the problem or wrong about how we should proceed to correct it. I was of the mind that they were wrong about the problem but it is becoming apparent that they have been wrong about he solution and things are going to go very badly over the rest of my lifetime and perhaps my children's natural lifetimes (it isn't at all certain that they will live so long) before we arrive at an equilibrium of hotter temperatures, new habitable areas (Canada will look nice) and a drastically reduced global population. We appear to be in a situation where everything is wrong and no fix that we would choose can possibly begin to help. I think the Catch-22 century came a little early.
Looks like once taco left the bitcoin shilling fell away.
How many shillings in a bitcoin?
I was reading through a summary of the entire history of BitCoin on SomethingAwful and I lost any respect I ever had for that project and its participants. I made the right decision to not waste any electricity on it.
"When information is power, privacy is freedom" - Jah-Wren Ryel
Because people like you never notice how much things actually *are* changing here in the real world.
Batteries are my favorite example. I'm constantly hearing people complain about reporting on battery breakthroughs in the lab, sarcastically saying, "Yeah, but when are we actually going to see these in the real world?" -- forgetting how much radically smaller and/or longer lived rechargeable batteries have gotten for increasingly high-power-consumption consumer electronics. Secondary cells have 5x'ed in energy density since the late 80s, and the trend shows no signs of slowing down. Even li-ion seems to have good life left in it (in particular, the anode; silicon (derided on Slashdot as a "sure, when will we finally see THAT?" tech) is now starting to replace carbon for part of the anode materials in commercially available cells, and it has a maximum theoretical anode energy density 10x that of carbon). Li-ion cathodes probably have a good 50% improvement left in them, possibly more; we'll probably see a migration to a Li-S chemistry after that, since that seems to be maturing the fastest (barring unexpected breakthroughs in Li-air, other chemistries, or electrostatic storage).
One nice thing about Li-S is that it's lower cell voltage with a much higher cell capacity, meaning that it's easier to get a specific desired voltage. Electrostatics would obviously be best (durability, temperature sensitivity, voltage discharge curve, etc), but they've also got the longest way to go. Li-air is oft hyped, but it too has an awfully long way to go. Then there's all sorts of other longer-shot contenders out there -- nickel-lithium, sodium-ion, aluminum secondary cells, etc. And then the question of whether flow batteries of any given chemistry will ever compete outside of a very narrow range of applications (such as grid storage).
Next to my desk we have an Ire Extinguisher. Our boss is really assertive, so we like the idea of having it.
Because they are scientist not engineers.
Scientist discover new stuff. Engineers use the new stuff discovered and makes use of it.
In terms of power. The more energy they can save/collect the more they have to use more.
It is the same when Gas prices are lower people buy larger cars. When prices are higher they buy smaller cars.
When the engineer get to use a new better power source smaller/lighter they will try to make it the same size/weight that it had before and use the extra energy it has to do more stuff with it.
Try to imagine how much battery life we can get with a laptop if it needed to follow the same performance specs of a 386 monochrome display laptop. You can probably get months of Uptime at high CPU usage.
If something is so important that you feel the need to post it on the internet... It probably isn't that important.
No that is a bad idea.
We need more energy diversity not less. Every energy sources has its advantages and disadvantages more sources will give us choice on what to use for our needs.
It is like choosing how to heat your home. You have Electricity, Natural Gas, Propane, Oil, Wood/Wood Pellets... Depending on your location you can choose an optimal solution.
If something is so important that you feel the need to post it on the internet... It probably isn't that important.
Long story short... no. First, that isn't how science works. If I'm an expert in photovoltaic reactions, my help isn't very helpful while you're trying to get a windmill working. Scientist are, in general, specialists, there is no degree in "cool alternative energy technology". Second, that's not how markets work. If I'm really close to figuring out how to, say, increase solar cell efficiency by 50%, thus making me rich; I'm unlikely to give up that work because we're working on wind power this month. Finally, it would be foolish to put all of our eggs in one basket. It's unlikely that any currently feasible alternative energy systems will be able to supply all the power people need everywhere.
Deserts are great for solar, coastline are get for wind and hydro, volcanically active areas are great for geothermal... None of them is a perfect tech that will work everywhere. Seattle would find solar farms all but useless, and there's not much easily available geothermal in Detroit. There are a few "magic bullet" technologies being researched, but they are very theoretical and a risky "bet the farm" idea. Sure, controllable and safe fusion power would solve all our problems, but no one is entirely sure it's possible.
I don't need a million points of light, just two points of multi-mode fiber and a 10 Gig-E router.
A comedy site, yes, but the article was based on verifiable facts. And I did verify many of them because I was shocked at the level of stupidity.
"When information is power, privacy is freedom" - Jah-Wren Ryel
Isn't he going to double my order if I order now? And maybe give me some completely unrelated product of little actual value for a bonus gift?
"That's right folks, order now and get two square feet of graphene for 39.99 million dollars. And this free ferret. It can all be yours for this low, low, price. order now!"
I don't need a million points of light, just two points of multi-mode fiber and a 10 Gig-E router.
With the refreshing power of orange!
Another area that's seen a lot of improvement is Low self-discharge NiMG batteries. A few months ago i got around to replacing my old set of rechargeable batteries with a new set of these and i've been pretty impressed. They hold a bigger charge for longer, and they even seem to recharge faster, though that might just my optimistic thinking on my part. My only complaint is the charger requires me to recharge them in pairs rather than one battery at a time, but that's just an issue with the design of the charger.
But unless you pay attention carefully or do some research on the subject it's easy to miss the improvements. They "just work", and how many people pay attention to the things that are working fine? Very rarely when an improvement makes its way to the shelves does it make a big splash. It might get hyped up in the marketing materials but we've all trained ourselves to ignore that stuff.
This Space Intentionally Left Blank
If your bitterest enemies are people who hack the heads off civilians, then I would say you're doing something right.
Actually, there is a degree in "cool alternative energy technology". My college recently started offering a PhD in "sustainability", whatever that is.
Well, this isn't a renewable energy source. It's just a funky property of Graphene. Far from generating any reasonable amount of energy this is just a low current induced by light. Could it lead to high efficiency solar power generation? Maybe, but that is extremely premature to think based on this story.
Taco left?
The new right fascists are bilingual. They speak English and Bullshit.