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Chevrolet Equinox fuel cell vehicle  (Source: DailyTech)
New catalyst is 2000 times more tolerant of carbon monoxide

The quest for alternative fuel sources that are cleaner, cheaper, and more abundant than traditional fossil fuels is underway around the world. Researchers are studying everything from battery power to solar energy and fuel cells.

Fuel cells hold great promise and have long been studied as alternatives to fossil fuels. Traditionally, the problems plaguing fuel cell-powered vehicles that run from hydrogen include how to produce the hydrogen cheaply and how to store it safely. Despite issues that still surround fuel cell-powered vehicles, a study conducted in June by Pike Research found that within the next decade 670,000 fuel cell powered vehicles would be sold each year.

Researchers at the Cornell University Energy Materials Center have made a breakthrough discovery that will make hydrogen fuel cell power much more economical. The breakthrough comes in the form of a new catalyst that uses platinum nanoparticles. Platinum is traditionally used in fuel cells as the catalyst, but platinum is expensive and can be easily deactivated in the presence of even low levels of carbon monoxide rendering the fuel cell inoperable.

The Cornell researchers have discovered a method of making the platinum catalyst able to withstand thousands of times more carbon monoxide. The process also makes the platinum catalyst material much cheaper to produce. The team created the catalyst using platinum nano particles that are deposited on a support material of titanium oxide. The team then added tungsten to increase the electrical conductivity of the catalyst. The resulting platinum catalyst is 2,000 times more resistant to carbon monoxide than a catalyst using pure platinum. 

That higher resistance to carbon monoxide means that the fuel cell can burn hydrogen with as much as 2% carbon monoxide in it. The researchers say this is very important because hydrogen derived from petroleum has a high concentration of carbon monoxide in it. The ability for the catalyst to withstand more carbon monoxide eliminates the need to clean the hydrogen as much, thereby reducing the cost of making hydrogen.



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RE: Meh...
By Dr of crap on 8/3/2010 10:26:17 AM , Rating: 1
Why are we getting the hydrogen from oil??????
How about fixing the probem of getting hydrogen from water.

We'd fill the tank with water,
the car would make the hydrogen on the spot
and run the fuel cell - simple no?


RE: Meh...
By wushuktl on 8/3/2010 10:40:58 AM , Rating: 2
i'm guessing it's not that simple and there will probably be some intermediate steps before something like that could be achieved.


RE: Meh...
By Solandri on 8/3/2010 3:59:24 PM , Rating: 3
It's not that it isn't simple - it's almost trivial to break water into hydrogen and oxygen. You can do it with some batteries, two wires, and a cup of water.

The problem is that each chemical molecule has a certain amount of energy potential. Water has a very low potential. So when you combine hydrogen with oxygen to make water, they drop to that low potential and release a lot of energy in the process.

But to do it in reverse, you have to add energy. The amount of energy you need to add to water to break it up into hydrogen and oxygen exceeds the amount of energy you get by burning them to create water again. So unless you have a cheap and abundant source of electrical energy (e.g. nuclear), there is no point cracking water into hydrogen and oxygen. You're better off just using the energy needed for the process directly.

Molecules of petroleum and methane store hydrogen at a much higher energy state. Their energy state is much closer to pure hydrogen than to water. So you add a little bit of energy to them to break off the hydrogen, then combine that with oxygen in the air to create water. The energy released in the second step is a lot more than the energy you used in the first step, so the net result is a large amount of energy released.


RE: Meh...
By tng on 8/3/2010 6:20:13 PM , Rating: 2
I know that Honda was tinkering with a home refueling station. This was part of the FCX Clarity project where they were leasing 300(?) of the fuel cell vehicles in the So Cal area where there are a handful of hydrogen refueling stations located at standard Shell gas stations.

Plug it in, add water, push start and after a certain amount of time you have enough hydrogen to fill your tank. Great thing to have in your garage IMO. If your electricity is cheap this is an alternative, but I would not call it green by a long shot, but still you don't have the exhaust emissions of an ICE from it so it is still greener than nothing.


RE: Meh...
By tng on 8/3/2010 10:44:47 AM , Rating: 2
So far, the process for "cracking" hydrogen from water is still a very energy intensive process and there is basically no gain from doing it this way.

I believe that now the most efficient way that is being used is by using natural gas.

The promise here is not weening ourselves off of hydrocarbons, but reducing the emissions from the tailpipe. A hydrogen fuel cell produces water as a by product.

The reason that this is important is that it makes the process of making hydrogen from any source less energy intensive by letting the fuel cell use hydrogen that is less pure. It also will help with the reliability of fuel cells


RE: Meh...
By jimhsu on 8/3/2010 11:49:40 AM , Rating: 2
There is really no point in producing hydrogen by electrolysis of water in a car because the net energy gain is at most zero (according to the laws of thermodynamics). The only setting in where electrolysis makes sense is possibly mass production of hydrogen in a centralized facility coupled to an efficient power source (nuclear, renewables, etc) - in which case you're back to square one. Otherwise, people derive hydrogen from fossil fuels because there is a gain of energy (relative to the amount of energy you have to expend to obtain the hydrogen).


RE: Meh...
By twhittet on 8/3/2010 11:00:30 AM , Rating: 2
Maybe if there were a magically small and efficient way of producing hydrogen from water.

If there was at least a large, but magically efficient way of converting, it would be viable to "fill up" like normal gas stations.

Since neither of these really exist yet, I'm not too excited.


RE: Meh...
By OnyxNite on 8/3/2010 12:25:12 PM , Rating: 3
You seem to have the whole concept backwards.

Hydrogen + Oxygen = Energy + Water

What you want is energy to run your car. So you need to provide Hydrogen and Oxygen. Just so happens there is enough Oxygen in the air that we get that for free. So we need Hydrogen for fuel to combine with the oxygen to get the energy (and water).

If your goal is to get energy to run the car and you have water that does you no good. To get hydrogen from the water you need energy and if you have an energy source to split the water then why the heck don't you just power your car with THAT energy source?


RE: Meh...
By nstott on 8/3/2010 1:46:16 PM , Rating: 2
No, not simple. Then your net energy would be zero at best, and your car would not move, because the energy required to break water apart is at best equal to the energy released when it recombines if you have 100% efficiency.

Believe it or not, there was a group at Samsung selling such an idea to the upper management, and they were buying into it. They kept that dog and pony show rolling for a couple of years to keep the funding coming in until management noticed that the technology wasn't going anywhere. I was surprised at how stupid company execs can be with regards to basic scientific laws, and many of them have advanced engineering degrees.

As far as using water to generate hydrogen, there are some working on using solar energy to do so to sea water as a way to "store" solar power in the form of hydrogen.


RE: Meh...
By marvdmartian on 8/3/2010 3:16:22 PM , Rating: 2
Just give me a few years to perfect my design on my Mr Fusion, and your wish will be granted! ;)


RE: Meh...
By namechamps on 8/5/2010 8:42:59 AM , Rating: 2
No water isn't a fuel source.

Electrolysis: Water + ENERGY = Hydrogen + oxygen
Fuel Cell: Hydrogen + Oxygen = ENERGY + Water.

See the problem?

Combined the "equations"
Water + ENERGY = Hydrogen + Oxygen = Energy + water

Now simplify
Water = Water

The energy produced in fuel cell (if 100% efficient) is exactly equal to the energy required to split water. With a perfect fuel cells you "car" would never move. It would simply convert a tank of water into water vapor with 0 watts of excess energy.

However in the real world fuel cells are more like 50%-60% efficient so it wouldn't even do that.


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