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Highly Efficient Oxygen Catalyst Found
eldavojohn writes "As detailed in the journal Science (abstract), a new compound composed of cobalt, iron and oxygen with other metals presents us with the most efficient way (found so far) of splitting oxygen atoms from water. These ten known compounds provide a reactivity rate that is at least an order of magnitude higher than what is currently known as the gold standard in such reactions. During their research, the team discovered that the reactivity is dependent on the configuration of the outermost electron of transition metal ions, which they exploited to develop this efficient catalyst. For rechargeable batteries and hydrogen fuel, this is exciting work from MIT's Jin Suntivich, Kevin J. May, Hubert A. Gasteiger, and Yang Shao-Horn, and the University of Texas's John B. Goodenough."
More than Goodenough.
But I thought it was hydrogen we wanted from water. What good is being able to split off oxygen?
Let's hope this works out better than the prospects for cold fusion.
Guess he really was Goodenough.
This device is perfect for those days when breathing is more important than drinking.
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Johnny B. GoodEnough
That last guy has the greatest name ever.
Is there a good theory on how catalysts work, so that scientists can use it to actually design new catalysts rather than "try a whole bunch of stuff and hope one works better"?
First, "at a rate 10 times the previous gold standard" is interesting, but meaningless. What is the actual rate, and how is it measured?
Second, what is the cost and availability of the materials needed for the catalyst? Does this require some kind of unobtainium? The article is very vague here.
Third, Is this something we can practically manufacture in any kind of real scale or are we talking microscopic results measurable only in the lab?
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Oxygen Destroyer is what we'll need by the end of next year.
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I just posted my own version before finding this
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Cobalt-9. All the water on Earth gets transformed due to this. Then explodes in a highly combustible way.
by Anonymous Coward: I, for one, welcome the shift from car analogies to pizza analogies. um.. overlords?
Chemical reactions do not destroy or change the elements in the compounds. Water is a Hydrogen atom plus an oxygen atom. Nature has been splitting water, then re-forming it for those same billions of years you're talking about. We're not really doing anything new here. We're just doing it in a new way.
When the hydrogen gets used, mostly it'll be "used" by recombining it with oxygen, either in a combustion reaction, in which case the water is re-formed and vented into the atmosphere where it will eventually become part of the rain, or it's recombined with oxygen in a fuel cell to generate electricity, at which point the water is re-formed, vents to the atmosphere, and becomes part of the rain.
Oh, also - we've 'liberated' a lot of 'new' water in the past 150 years - when we pull coal, oil, natural gas, and peat out of the earth to burn it, there's hydrogen in all those fuel sources (as well as carbon). Hydrogen which had been locked away for millions or billions of years, and reacts with oxygen in the atmosphere to form water (technically, it's not 'new water', really, since it started as water aeons ago, and was absorbed into the living plants, mosses, bacteria etc which eventually turned into coal, oil, natural gas, and peat).
Slight slip up while typing. What I typed was, "Water is a Hydrogen atom plus an oxygen atom.". What I *meant* to type is, "Water is two Hydrogen atoms plus an oxygen atom."
Do you still run electricity through the water, but first you 'dope' the water with the catalyst, and the hydrogen/oxygen separation happens with same rate with less energy input/faster rate with same input?
They mentioned something in the article about an "artificial leaf", so does that mean that you use sunlight as the energy input instead of electricity, and the sunlight drives the reaction with the catalyst?
Sorry, there is no way to reduce the amount of energy it takes to separate water into hydrogen and oxygen.
This magic catalyst makes it go faster, but there is an absolute, defined energy required, and it would take an Act of God to modify this.
If you want hydrogen fuel, great, but you have to put in as much energy as you get out later. Some forms of energy are more convenient than others, for instance "sunlight in desert" is less useful than, say a couple gallons of gasoline. Catalysts let you shuffle them around faster, but they do not let you set aside the laws of thermodynamics.
Don't take life too seriously; it isn't permanent.
Wait, so you're saying that we were already at 100% efficiency? My understanding of it (which may be flawed), is that previously, with electrolysis, a lot of energy was being *wasted*? That is, it wasn't being used to split they water, but I dunno, generate waste heat or something?
So, unless you are at 100% efficiency, you should be able to generate hydrogen with less energy if you can find a way to reduce the *wasted* part of the energy. There is, sure, an upper limit on how low the energy can go, since I do agree that there is an absolute amount of energy always necessary to split the compound apart.
So, does this catalyst reduce the waste?
So? Using "renewable" energy sources to feed the catalyst process to store hydrogen is much better than all the resources used to explore and dig oil and gas, plus the lower environmental impact.
Not exactly.
If the catalyst were to lower the activation energy to, for example, the amount of energy present in water at 219 kelvin (around 4 degrees), then refrigerated water would simply fizz off when exposed to the catalyst. Water kept colder than the standard 4 degrees in the fridge--say 3.5 degrees--would remain water until some external force applied heat.
Of course we get the other obvious problem here. When you burn hydrogen and oxygen, you get water and heat; when you reverse this process, obviously, you will require energy input (likely heat, sometimes electricity). So the thing will probably get colder until it passes 4 degrees, then cease reacting.
This means if you use it for, say, a car, then you will want to run the exhaust system directly through the fuel (water) tank from the inside, through a heat exchanger, to keep the water warm by reclaiming waste heat. It also means your major commodity fuel is stored heat energy. It also means that as you burn this off, you're going to get colder despite any reclamation system: your car will eventually need to settle and warm up. The car won't work in cold weather. And so on.
More importantly, the amount of energy you get out per unit is equal to the energy lost in that split: to raise the temperature of an engine to a few hundred degrees, you have to drop the temperature of an equivalent mass of water by that amount. If you're running electric through hydrogen fuel cells, same deal: to generate 300kW of power, you're sucking heat out of that thing at a rate of 300kW load (equivalent to an absolutely 100% efficiency 300kW refrigerator!). If you're doing electrical hydrolysis supported by catalyst, you still have the same problem: it won't self-power any better with or without the catalyst, because you need to power the electrodes as well as the engine.
Water is not a magic solution to anything.
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This could be a source for water purification.
I would think you would need some way to reduce the salt first tho.
Perhaps large solar based plastic evaporator collectors. The condensate would flow into cells based on these catylsts producing clean water.
The "leafs" they showed here a few weeks ago might be a better solution tho.
She was like chocolate when she drank... semi-sweet at first and then increasingly bitter.
"plus the lower environmental impact."
This is a statement I see repeated very frequently (in some form or another) by environmentalists. It may even be true. The problem is, I've yet to see a rigorous defense of this claim. . .
Most environmentalists don't seem to take into account:
The rare earths and toxic compounds needed to build lots, and lots, and lots, and lots of Wind Turbines, Solar PV panels, or Solar reflectors (for concentrated solar-thermal power plants).
When you mine rare-earths, you will probably also generate waste streams. How toxic or radioactive are those "tailings" going to be? What is the plan for safely dealing with the tailings?
The massive amounts of concrete, aluminum, steel, and other resources which will need to be produced to build lots, and lots, and lots of wind turbines and solar systems?
The fuel which will be burned by all the construction equipment (bulldozers, concrete trucks, cranes, transport trucks for the components to build these things)?
Right now, I'm a bit worried that the "green" revolution will end up doing more harm to the environment than good, though I hope to be wrong.
You might have to have pure water to begin with for this catalyst to give you pure hydrogen and pure oxygen. They probably started with DI water from their RO unit, before they added whatever alkali they needed to activate the catalyst.
What they fail to mention is that it requires Dihydrogen Monoxide which is highly dangerous to humans when inhaled and can lead to suffocation. They should immediately ban this voodoo.
In case you aren't just being an ass, I'll avoid being one (just this once) and ask...
How does your list of ecological atrocities compare to that for the extraction of fossil fuels? Unless it is wildly out of balance (and it's not), the net gain comes from not injecting X amount of mega-million-years-old sequestered carbon per joule created into the atmosphere.
"I guess the moral of the story is, don't paint your airship with rocket fuel." -- Addison Bain
You are correct, there is a definitive minimum energy required to split up a water molecule and get out hydrogen and oxygen. This energy is the same as the potential energy that would be released if you burned the two gases together in an exothermic reaction, getting the water back. Typically though electrolysis uses much more energy than that, because there is a certain "activation energy" threshold that you have to reach before the reaction can occur. Without a catalyst you have to put in extra energy to get over this barrier, and the extra energy left over at the end turns into heat. If splitting the water molecule is like pulling a weight a certain height up a hill (in terms of potential energy), the activation energy is an extra hump you have to pull the weight over, after which the weight is free to roll back down to the final height. See this illustrate here: activation energy plot.
So a catalyst does not let you get energy for free, but it lets you turn electrical energy into chemical energy of hydrogen and oxygen with less wasted energy.
A defense is actually fairly easy because you're trying to compare apples (infrastructure) and oranges (fuel) when saying they don't save us much.
The turbines, panels, reflectors, etc are 'infrastructure' which exists in the current system of power plants as well. So generally speaking those cancel each other out - obviously not exactly but since you have to build multiple power plants composed of massive amounts of steel and other components. That requires significant mining and other processing before it is available which is the same as the infrastructure for renewable.
Both systems have infrastructure that has to be built.
Two areas that renewable shines brightly are:
location - your power plants can be on your own roof/backyard, so much less transmission capacity is needed.
fuel - they don't have the ongoing fuel requirements that conventional systems have. Which of course requires mining and the other processes you talk about.
On top of that renewable generally doesn't pollute the environment during operation like fossil fuels do. (Nuclear doesn't pollute (much) during operation but has significant risks when things go bad. A windmill just falls over. It doesn't render the area inhabitable for decades.)
People in cars cause accidents....accidents in cars cause people
The catalyst is highly active but not to be confused with efficiency.
Ideally water oxidization would occur at 1.23 V vs RHE (higher is inefficient)
IrO2 operates at low potentials but is less active
(i.e. it requires more catalyst for the same amount of current)
This is not a bad thing more efficient but less active.
See, this is one of those writeups that sounds entirely plausible, but isn't quantified.
You are assuming an aweful lot. This is NOT a rigorous defense of the claim. Has anyone done an actual study, which has been peer-reviewed and accepted as reasonable, which really tries to put some defensible numbers on such claims?
I'm not saying you're wrong. I'm saying, I don't see the data. I think a lot of people underestimate just how much infrastructure you need to get a lot of "renewable" power.
Let's take, for example, one of your claims:
"location - your power plants can be on your own roof/backyard, so much less transmission capacity is needed. "
This is wrong. It's not wrong that you can put solar panels on your roof. What's wrong is that you still need all the same infrastructure PLUS your solar panels? Why? Unless you are going to completely disconnect from the grid, then you need all the same infrastructure.
ALSO: Some buildings are not suitable for being powered by rooftop solar panels - high-rise office buildings, high-rise apartments/dorms, high-rise anything. Even "regular" non-high-rise apartment buildings would likely not be able to provide enough power from just their roofs, because the population density of the building, and thus the energy-consumed per square foot, would be higher - more fridges, stoves, hot water heaters, lights, TVs, washers, dryers, etc per square foot. High-energy use buildings like grocery stores (all those fridges and freezers probably mean you can't get enough power from just the roof alone), restaurants, hospitals, factories.
It might be that putting solar panels on every roof can cut down our need for off-site power, but it *cannot* eliminate it for a very significant number of buildings.
So, we will still need "The Grid". But, we're trying to get most of our power from wind or solar, so people suggest, let's build lots of industrial wind/solar farms out in the hinterlands. Now, we've just added a whole new, additional set of "Grid" infrastructure that's necessary to transport all that power around.
Let's look at your other claim: That because they don't need fuel, it stands to reason they need less mining activity, ultimately, than oil, coal, or nuclear. That may or may not be the case. The thing is, you need about 3 and a 1/2 times as much 'nameplate capacity' for wind or solar to equal a fuel-based power plant.
Why is that? Because most fuel-based power plants have a capacity factor of about 80-90% (varies by type - nuclear currently has capacity factors around 90%, for example). Roughly speaking, capacity factor is how much power a plant actually produces, verse the theoretical maximum capacity. So, a 1 GW Nuclear Plant will *actually* produce about 900MW of power, overall.
According to the Wikipedia page on Capacity factor, Wind farms typically get around 30% capacity factors. Solar PV gets around 15% (in Arizona, one of the most ideal locations on earth, that jumps all the way up to 19%, woo).
You can overcome the capacity factor gap - by building more capacity, and/or some sort of storage.
So, now the million dollar question: Does the additional mining and manufacturing activity necessary to build massive amounts of renewable energy infrastructure offset the 'gains' you expect from not needing fuel. I think it's entirely possible that could possibly be the case.
I hope someone know of any study that actually compares these things. I'm sure it would be very interesting, enlightening reading. Especially if compared against nuclear energy, since nuclear power plants don't emit any pollution, except in extraordinary events that only happen to one plant every 15 or 30 years (though there is some pollution in the fuel mining, enrichment and manufacturing).
so how long until i get my cheap robotic fish gills?
that is the real question.
This is wrong. It's not wrong that you can put solar panels on your roof. What's wrong is that you still need all the same infrastructure PLUS your solar panels
Correct. However I think you'll agree you'd need less of the infrastructure for power transmission because more power is being generated at the point of use. This is a significant reduction in what renewable needs versus conventional.
Some buildings are not suitable for being powered by rooftop solar panels
Solar film panels that stick to the windows are already in production. Now every window is a solar panel. Again reducing the energy you need to generate/transmit.
you need about 3 and a 1/2 times as much 'nameplate capacity' for wind or solar to equal a fuel-based power plant.
Refuting my assumptions with your own unsubstantiated statements isn't much of a refutation ;-) I am saying that you don't have fuel requirements with renewables, fossil fuels will always have them. Given the hundreds of millions of dollars individual power plants generally cost to build, I'd venture you could easily cover that cost through renewable installations over the lifespan of the systems since there is no fuel for the renewables. Hell, normal residential solar panels pay for themselves in 10-15 years, less for larger systems. Small to big doesn't always follow for correlation, but it's a pretty good indicator that significant savings exist to be had.
Nuclear is a different animal entirely. It will have to be part of our solutions for the next 100 years or so I'm guessing. The risks associated with it though are not worth the benefits long term if you can provide the same energy at the same costs. There's just no reason to use nuclear except perhaps on long space voyages where fuel/sunlight aren't readily available.
The costs of nuclear are mostly in the risks. Without the government backing the loans, nobody would build them - the risks are simply too great financially. Then there's the waste storage issue - something we still haven't solved. Modern society hasn't existed for more than a century and yet we need to store this stuff 'safely' for up to 1000 years. I just don't see that as a sustainable path forward.
People in cars cause accidents....accidents in cars cause people
Two hydrogens and one oxygen walk into a bar. The three get together and say, let's get wet!
It's friday... cut me a break.
Just when you make it idiotproof, some idiot builds a better idiot.
"Refuting my assumptions with your own unsubstantiated statements isn't much of a refutation ;-)"
Are you referring to the claim about needing about 3 and 1/2 times more nameplate capacity? Because I did substantiate it. I talked about the difference in capacity factors, which is where I derived that figure from. If the capacity factor of wind is 35%, you need almost 3 times as much capacity to generate the same power. If the capacity factor of Solar is, at best, 20%, you need a bit more than 4 times as much capacity.
Gold standard? I thought Platinum was the pretty standard cat in such cases?
You are making the assumption that "one nameplate" costs exactly the same for all types of power generation. Perhaps solar costs more, perhaps less, for a "namepate" (a weird term I have never seen before). It does not confirm or deny your argument.
Also your capacities for solar are comparing them to how much energy they would generate if they faced the sun at a right angle for 24 hours a day. You might as well mark the capacity of a coal plant based on the potential energy of every C+H bond in the coal, not on what is expected to be burnt.
It's not going to get colder. You might want to study thermodynamics a bit!
To turn water into hydrogen + oxygen takes energy input. The huge deal with this announcement is that supposedly a larger percentage of that energy is used to split it, rather than turning *INTO* waste heat.
If your water-splitter got colder then you are using more than 100% of the input energy. Such a technology would have a lot larger implications than just making solar energy cheaper!
Excuse my ignorance if this is a dumb question; but as a scuba diver I'm hoping this would be useful to build artificial gills... or is the catalyst process still too slow to keep up with human oxygen consumption?
No doubt here, you are being one. carbon (in the form of carbon dioxide) is not a pollutant.
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for producing large amounts of hydrogen from water, is it cheaper per ton of hydrogen compared to the sulfir-iodine cycle with a nuclear reactor supplying the heat? http://en.wikipedia.org/wiki/Sulfur-iodine_cycle
I don't have time to address all your points right now but consider this - even if the capacity factor for solar is as low as you claim, it's very well-matched to demand in most of the US southwest and similar developed countries. Imagine how much better it would have been for Texas if their grid had a couple GW of solar ( and that much less wind), especially through the hot, dry weather of the last couple years. Also, why does it matter that solar isn't suitable right now for every possible type of building? Is there a shortage of large flat roofs and parking lots where you live? I can assure you that not the case of most of the ideal places in the Western world. If there was a Solar Mandate in the Southwest to, within 10 years, install PV on every suitable commercial, gov't or military roof and build solar thermal plants in the very low-density areas, with at least 1/4 of them having 6-8 hrs storage, it would be a very different America, with a lot less coal crap in the air.
Pain is merely failure leaving the body
Nisssan's recent announcement of a marketable fuel cell http://www.gizmag.com/nissan-doubles-power-density-with-new-fuel-cell-stack/20156/, combined with this discovery might just make the economics of EV's goodenough.
It's not going to get colder. You might want to study thermodynamics a bit!
To turn water into hydrogen + oxygen takes energy input.
Look, it's this simple: Hydrogen + Oxygen = Water + Energy; therefor Water + Energy = Hydrogen + Oxygen.
As I said, a catalyst lowers the activation energy of a reaction. Think of it like an electric mold, a molecule shaped such that its charge structure attracts but also stretches another molecule. So the hydrogen pulls further from the oxygen, but no reaction occurs with the catalyst. Because of this stretch, the bonds are weakened, and lower levels of energy can break them.
Now, if you reduce the reaction energy enough, those bonds will break by themselves. This won't happen at absolute zero, ever; because combining these things releases energy, it stands to reason that breaking them for free and then recombining them would forever derive an endless source of energy. That won't happen. You're going to have to put energy into it. Reducing the reaction energy to below ambient thermal energy is sufficient to cause the molecule to fracture by consuming the environmental heat--for example, in the case of 2H2O2 into 2H2O and O2, although that releases heat on reaction (which fuels continued reaction).
If not, you need to add more energy. Electricity, heat, whatever. If it absorbs electricity, you won't have enough heat output from burning to drive the electrodes to split the molecules indefinitely--or else, it will also absorb heat and require more power as it cools down to continue the reaction, eventually freezing. One way or the other, you'll eventually run out of power in the closed loop system.
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I'm not clear if you are *actually* claiming that a catalyst could in theory be so good that the reactor will freeze. If so you might want to check your facts.
Yes the reaction will stop if you lower the energy input enough. What I am saying is that it MUST stop before the energy input is lowered below the actual amount of useful energy contained in the reaction products. Therefore there will always be a non-negative amount of input energy going into waste heat. There is NO way the reactor will get colder.
If the reactor got colder you would not need solar energy or anything. Just connect it to the ground and you will get unlimited hydrogen as long as you don't lower the entire earth to 0 kelvin (or run out of water).
Look. It takes a certain amount of energy to burn things. Like paper has to reach a temperature of, let's say, 451 degrees farenheight to ignite. Now, in the presence of a catalyst (say a catalytic gas), paper's activation energy becomes lower. Paper will now ignite at 378 degrees farenheit. With me so far?
If we bring the temperature below 378 degrees farenheit, the paper will stop burning. Of course, once you ignite paper, the combustion reaction releases energy, keeping the temperature up and allowing more paper to burn. Thus the catalyst serves to make initiation easier by requiring a lower initial energy load--and the paper burns faster because the amount of energy absorbed to break bonds is reduced as well, keeping more free energy to ignite other paper.
Now let's say you take this in reverse. Take CO2 and H2O and turn it into hydrocarbons, like methane. Methane burns like paper and releases heat. To make methane, you take CO2 and H2O, add a certain amount of heat, and the output is Methane. We'll call this temperature 800 degrees farenheit (although it's a number of joules of energy you have to add to the molecules to form bonds, really).
Now you add a catalyst. Line the cylinder with something that allows the system to form methane at 600 degrees farenheit. The number of joules of energy needed to initiate bond formation is reduced; however the total energy required to make those bonds remains the same. So if the process normally begins at 800 degrees farenheit and consumes 100 joules of energy, it will now begin at 600 degrees farenheit and consume 100 joules of energy. The advantage here is that you can use a cooler flame to begin the process, thus avoiding using some amount of fuel to raise the temperature, and avoiding an appreciable loss in the system (a hotter system will transfer more energy more rapidly to cooler mass, even though insulation; insulation slows the process, but so does equalizing temperature between both masses in the first place, hence a cooler reaction vessel).
If we extrude this out, let's say you find a magic catalyst that makes the energy of activation equal to the ambient energy available at, say, 50 degrees farenheit. It's 90 degrees farenheit outside today. By leaving your vessel in the warm ambient air, your vessel will automatically generate methane from CO2 and H2O. Mind you, it still absorbs 100 joules of energy each time it forms a methane molecule. As a result, ambient heat is consumed: the vessel becomes colder than the atmosphere around it. If the reaction occurs sufficiently quickly, the vessel will eventually freeze--a temperature of 50 degrees farenheit will be reached, and the reaction will cease to occur until enough energy enters the vessel to form a bond, in which case a molecule of methane will promptly be created and all reaction will again stop pending further energy absorption into the medium.
If you create a catalyst that splits water with a low enough activation energy, it WILL reduce the temperature of the water continuously until it reaches the temperature at which the reaction begins--the temperature at which the amount of energy in the molecules is below the activation energy required. Thus if you can make water react at 40 degrees farenheit, the system will freeze at 40 degrees farenheit--you'll have to warm it up or it just won't work anymore. If the activation energy comes in the form of electricity, however, then you will continuously consume energy from the input electricity; it will prove impossible to separate the water into hydrogen and oxygen, burn that hydrogen and oxygen, use that to generate electricity, and power the electrolysis process to generate more hydrogen and oxygen. At some point, you will need an external fuel source, whether the reaction occurs by means of heat or electricity input.
In other words: you will NEVER make a self-sustaining machine in which you dump water in, seal it off, and then repeatedly recycle the water produced by ignition or any ot
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