Slashdot Mirror
Diamonds Are a Fuel Cell's Best Friend
Roland Piquepaille writes "Researchers at UC Davis have used nanocrystals made of diamond-like cubic zirconia to develop cooler fuel cells. Even if hydrogen fuel cells have been touted as clean energy sources, current fuel cells have to run at high temperatures of up to 1,000 C. This new technology will allow fuel cells to run at much lower temperatures, between 50 and 100 C. Obviously, this could lead to a widespread use of fuel cells, which could become a realistic alternative power source for vehicles. The researchers have applied for a patent for their technology, but don't tell when fuel cells based on their work are about to appear."
As apparently no one bothered to read even the summary, let me be the first to say there is NO DIAMOND in this solution, real or artificial...It's cubic zirconium, which is a sparkly gem that is often used to simulate diamond, but has neither diamond's chemical makeup, nor its hardness.
ad logicam Claiming a proposition is false because it was presented as the conclusion of a fallacious argument.
While we want fuel cells for transportation purposes to run at low temperatures, it is not obvious that this is appropriate for fixed-point fuel cells. Low temperature fuel cells can handle hydrogen, but I am unaware of them being able to handle hydrocarbon fuels at reasonable loadings. Typically you need temperatures of a few hundred degrees C to enable the molecular reforming for handling of hydrocarbons. This is reasonable for fixed point systems which can be kept at temperature. The higher temperature also allows the use of lower cost catalysts.
1. Diamond? WTF is diamond doing in the title? Cubic zirconia's nothing like diamond unless you believe the ads of people trying to sell you rings with CZ's in them. (And if you've played with gemstones, you might be able to spot those with your bare eyes: they have a 10% different index of refraction of light.
2. Zirconia has been used for a fuel cell 'catalyst' for a while. Here's a reference to a two-year-old paper about a related fuel cell system.
3. I say 'catalyst' in the above, because zirconia's only sort of a catalyst. While the zirconia remains more or less zirconia, it's not just offering a surface for reaction chemistry: it's actually exchanging oxygen with the reactants during the reaction.
4. Still, it's interesting and weird that the electrical potential is being transferred by protons, rather than electrons (as per TFA.) I'm not familiar with that, just with holes and electrons, so that bears more reading.
Nostalgia's not what it used to be.
CZO (Actually Zirconium-Yttrium-Oxide) is only similar in appearance to diamond. In all other respects it is completely different.
The most important difference is that diamond does burn in oxygen while CZO is an excellent oxygen conductor (yes, a crystal that conducts ions by a hole transport mechanism). This is also the effect that is used in fuel cells. There is really no relation to diamonds. Pure popular BS-science.
First, it's a Roland the Plogger story, so it's probably wrong.
Second, it's another one of those "we made some minor advance in materials science on a laboratory scale and this will change the world Real Soon Now" stories. It's too early to be making claims like that. All they have is a new material that might be good for something. Maybe.
Third, it's one of those surface chemistry/crystal chemistry as "nanotechnology" stories. "Nanotechnology" has turned into a buzzword for getting funding for surface chemistry work.
Not that I disagree with you that Hydrogen is probably a bad choice for vehicle fuel, there's a few things that are worth pointing out:
1. "A BOMB" Presumably you meant _A_ (as in singular) bomb, and not an atom bomb. Anything highly flammable can be confined and made to explode. Obviously, hydrogen is no different...but a pressurized tank is really no more likely to explode than a gasoline tank. As the hydrogen is released from a compromised vessel, it will burn vigorously, if it has been ignited, just like natural gas, propane and even gasoline. The one nice thing about hydrogen is that it is lighter than air, so if it does leak, it goes up into the sky and dissipates, unlike gasoline vapors, which hug the ground and will occasionally find an ignition source to flash back to the point of the leak.
2-5. Agreed
6. We move natural gas around in pipelines, the same could be done with hydrogen gas. However, it's that expense thing that comes into play. Since the cheapest way to produce hydrogen gas is from steam reformation from natural gas, it would be more economically advantageous to produce hydrogen at least regionally, if not on a smaller scale instead of transporting hydrogen long distances in pipelines.
7. Pretty much the same thing that happens to large propane tanks. If they catch fire, they can BLEVE (boiling liquied expanding vapor explosion). However, if the tanks are placed underground, the point of ignition for the leak would be enough of a distance away from the tank that this would not be a problem. Remember, hydrogen needs oxygen to burn, too.
8. Right now it is, anyway. Might be okay for city buses, perhaps.
9. Agreed
10. One rather well founded piece of speculation is that it will become a module of a system like many components currently in cars that is simply replaced or swapped out. Even master auto technicians don't crack open the case on a computerized engine control module to fix a faulty component on a board, they simply swap out the whole box, potentially sending the faulty unit back to the manufacturer. Why couldn't a similar principle apply here?
Also add 11 to your list that hydrogen is usually just an additional (and perhaps unnecessary) step in energy conversion, not an energy source in and of itself. Everything is solar powered, it's just a matter of how many steps of conversion happen between the point where the solar radiation reached earth and where someone puts it to practical use.
Okay, I've done the Slashdot thing. Countered some of your arguments, although I agree with your stance on the use of hydrogen in privately owned passenger cars. Heck, I even worked in a car analogy (sort of..). Ten reasons on electric cars or ethanol hybrids? Probably can't come up with ten, but the best is "the technology/infrastructure is just not quite there yet"...just the same as it is with hydrogen.
Not that I disagree with your point but:
1 - If you drive a liquid H2 car, you're driving A BOMB! One that can never be turned off, unplugged, get in a bad crash, or run out of fuel or it will explode!
Sure but that's pretty much true of any energy storage system. It's not like gasoline, or for that matter modern batteries are all that safe either. Also any tank capable of storing compressed H2 is going to be inherrently pretty strong.
- what happens if the great big H2 tanks at the filling station are involved in an earthquake, terrorist attack, or extended power outage?
The gas escapes and dispurses? We already have tanks and pipelines with propane and natural gas all over the place and those are far more dangerous than H2 which at least has the advantage of being lighter than air.
- it's FUCKING expensive!!!
It looks to me like generating H2 via electrolysis of water is in the same general ballpark effenciency wise as charging/discharging batteries (both somewhere in the 50% range).
- Solid (metal infused) H2 tanks take approximately 6-8 hours to refill with enough H2 to drive 150 miles. This is MUCH worse than electric only cars. (In fact, using Toshiba's new battery technology, we could refuel electric cars in 90 seconds, to 90% charge.
- we don't have ANYTHING resembling an industry for transportation, storage, or pumping of H2.
It's not like we have the infrstructure in place to charge an electric car anywhere near that quickly either in most places. That's a LOT of power.
- it's too damned big of a system. Cars would have to be the size of hybrid SUVs and loose either 2 seats or the trunk to run on H2 safely.
Same problem with batteries.
- will you trust a grease monkey to fix an H2 powered engine? (no offense to my many talented automotive engineering friends) Do you have any idea what it might take to fix an engine like this? can it even be repaired at the component level safely?
H2 engines are pretty much the same as gasoline engines so I'm not sure why you think they would be more dangerous to work on. Working with an electrical system capable of delivering thousands of watts for an extended period of time doesn't sound exactly safe either.
..And of course, the lovely thought of driving around in my car with a nice tank of hydrogen fueling me, knowing that I'm just a wreck away from a hindenburg style disaster. "Most deaths were not caused directly by the fire but were from jumping from the burning ship. Those passengers who rode the ship on its descent to the ground survived. Some deaths of crew members occurred because they wanted to save people on board the ship."reference http://en.wikipedia.org/wiki/LZ_129_Hindenburg
"The Nature of Hydrogen:
* Hydrogen is less flammable than gasoline.
* Hydrogen disperses quickly.
* Hydrogen is non-toxic.
* Hydrogen combustion produces only water.
* Hydrogen can be stored safely. Tanks currently in use
reference http://www.hydrogennow.org/Facts/Safety-1.htm
Both websites refer to the causes of the Hindenburg disaster, pinning the blame on the blimp material for the largest part of the fault.
The Hindenburg really wasn't a hydrogen disaster, it was an airship disaster that happened to also involve hydrogen.
Please. Don't try me. Do you think that at the turn of the century, when this campaign was launched and about 10% of people owned their own homes, that women really wanted men to waste two months salary on a ring?
Women told De Beers marketing they don't. Based on that, De Beers developed a campaign to promote surprise proposals and the 'two months salary' rule. That is a matter of historical record. Whether women of the day really wanted a flashy ring or not is something you and I will never know.
But sure, try to paint me as a naive fool. Set up a strawman involving a complete tangent and knock it down. Go nuts. You come across as a petulant whiny bitch, as usual.
- None can love freedom heartily, but good men; the rest love not freedom, but license. -- John Milton
As someone who works in the fuel cell industry (an who works with hydrogen on a daily basis), I can unequivocally say I'd rather use hydrogen than gasoline as a fuel.
Your scenario of the fuel tank "blowing" presumably refers to a mechanical rupture. Either fuel would quickly escape from the tank and potentially form an explosive mixture with air. Because gasoline vapor is more dense than air, the explosive air/gasoline mixture tends to hug the ground and stay near the source of the vapor (i.e. the liquid gasoline remaining in the tank or on the ground). A spark would ignite the explosive mixture and create heat which would quickly vaporize (and ignite) the rest of the gasoline.
Hydrogen is the least dense of all elements, so a potentially explosive mixture rises away from the source (ruptured tank). Also, hydrogen disperses exceptionally rapidly in air (almost 600% more quickly than gasoline vapor), which allows an explosive mixture to quickly disperse and dilute below the lower explosive limit of 4% in air.
Finally, the energy density of hydrogen is much less than that of gasoline. That's a great advantage from a safety standpoint. Fuel cells are extremely efficient (much more so than combustion engines); that's how they are able to overcome this energy-density "deficiency" with respect to hydrocarbon fuels.
Perhaps you're thinking about diamond's company researcher from the 1970's:
Women are in unanimous agreement that they want to be surprised with gifts.... They want, of course, to be surprised for the thrill of it. However, a deeper, more important reason lies behind this desire.... "freedom from guilt." Some of the women pointed out that if their husbands enlisted their help in purchasing a gift (like diamond jewelry), their practical nature would come to the fore and they would be compelled to object to the purchase. -Daniel Yankelovich, Inc. (working for) N.W. Ayer (working for) De Beers
And the observation that people give gifts that are fancier than what people would choose to get themselves is hardly limited to De Beers or engagement rings. What do you think the Christmas shopping season is all about?
Anyway there's no reason to make such angry arguments, when your arguments are based on pulling made-up statistics out of your ass. If you're actually interested in the history of diamond marketing (I suspect you're just interested in being a jerk) there's an interesting (if dated) take in The Atlantic Monthly.
Slashdot: providing anti-social weirdos a soapbox, since 1997.