Posted on 12/08/2006 12:34:35 PM PST by Red Badger
Attaching titanium atoms (blue) to the ends of an ethylene molecule (yellow-green) will result in a capsule-shaped complex that absorbs 10 hydrogen molecules (red).
Results of modeling studies by the National Institute of Standards and Technology (NIST) and Turkey’s Bilkent University indicate that attaching titanium atoms to the ends of an ethylene molecule will result in a capsule-shaped complex that absorbs 10 hydrogen molecules. The results open a new avenue in the pursuit of materials that will enable efficient solid-state storage of hydrogen.
Ethylene is the inexpensive building block of the most common plastic.
The team’s calculations show that attaching titanium atoms at opposite ends of an ethylene molecule (four hydrogen atoms bound to a pair of carbon atoms) will result in a very attractive “two for” deal. The addition of the two metal atoms results in a net gain of up to 10 hydrogen molecules that can absorb onto the ethylene-titanium complex, for a total of 20 hydrogen atoms. As important, the engineered material is predicted to release the hydrogen with only a modest amount of heating.
The absorbed hydrogen molecules account for about 14% of the weight of the titanium-ethylene complex. That’s about double the Department of Energy’s minimum target of 6.5% for economically practical storage of hydrogen in a solid state material. Although significant challenges stand in the way, solid state storage is preferred to storing hydrogen as a liquid or compressed gas, both of which require large-volume tanks.
The success of future hydrogen and fuel-cell technologies is critically dependent upon the discovery of new materials that can store large amounts of hydrogen at ambient conditions. —Taner Yildirim, theorist at the NIST Center for Neutron Research
Yildirim and collaborators have been searching for routes to develop these needed materials. Their earlier research has pointed to several candidates, including carbon nanotubes coated with titanium atoms. Difficulties in securing bulk amounts of small-diameter nanotubes and other challenges have foiled efforts to create these materials in the laboratory.
The team anticipates that ethylene-based complexes, made with titanium or other so-called transition metals, will prove easier to synthesize and, then, to evaluate for their potential for high-capacity hydrogen storage.
Resources:
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“Transition-Metal-Ethylene Complexes as High-Capacity Hydrogen-Storage Media”; E. Durgun, Ciraci, W. Zhou, T. Yildirim; Phys. Rev. Lett. 97, 226102 (2006)
FUEL CELL Ping!
I don't like the concept of hydrogen for motor fuel at all.
20 gallons of gasoline will blow you to smithereens with just a spark. Hydrogen fuel cells can't.......
So they've almost invented dry water? I know... I'm just joking. :)
"The success of future hydrogen and fuel-cell technologies is critically dependent upon the discovery of new materials that can store large amounts of hydrogen at ambient conditions. —"
seems like a higher priority would be to find a source of hydrogen , last I checked there was none laying around in back the yard. But as long as they continue to snow ball those holding the purse strings, fuel cell technologies will keep showing up at the front door.
My 600' driveway (uphill) is currently coated with 1/2" of very dangerous dry water.
It's already been done.
My dislike of hydrogen has nothing to do with that. Why go and create hydrogen when there are readily available fuels that are not a net energy loss, like natral gas, fosil fuels, etc.
LOL, uphil both ways, covered with snow, huh?
Why?
The thing I find absolutely most interesting about all of the envirowackos that profess that hydrogen is the be-all and end-all of fuels is this: if they knew any elemental chemistry or thermodynamics they would know that water vapour is a WORSE greenhouse gas than carbon dioxide. But far be it from me to inject science into the debate.
Yes, there are plenty to choose from for now. But eventually they will run out. Maybe not in a hundred years, but they will deplete at an ever increasing rate, as populations grow and industrialization of 3rd world countries gets more and more people into cars and trucks. Just look at what strain India and China's demand for oils has done to the world markets, then add Africa and South American countries over the next ten to fifteen years. Somethings gotta give.........
a) Titanium is not exactly an abundant material
b) How do you get the Hydrogen to release from the cell once attached?
c) How much energy does it take to synthesize the hydrogen fuel in the first place?
d) What is the overall efficiency of producing/storing/recovering/using Hydrogen fuel vs sucking oil out of the ground/storing/processing/using?
The fundamental problem with alternative fuels IMO is that fossil fuels are fundamentally cheaper, easier and more efficient to produce than any other source of fuel.
Now, you can add the geopolitical aspect of FFs, the fact that most of them are under Islamofascist states or communist states...now that is a different issue... but lets not sell hydrogen fuel as a cheap, efficient or easy solution.
hard, dry water. When tread upon by rubber wheels, returns partially to liquid state. If I wait long enough, some of it will pass on to gaseous state. Isn't matter wonderful. (Hopefully it will not reach the plasma state anytime soon)
Looks like you have a lot of stored hydrogen over at your place. Maybe they could come over and extract it for you?
Not true. Titanium is the ninth most common element in the earth's crust.
Five bonds to the carbons?????
Yes, Bonds......Five Bonds........
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