For years, researchers have looked for ways to store hydrogen in apractical and cost-effective way for use in vehicles. It hasn't been easy for scientists like Rice University mechanical engineering and materials science professor Boris Yakobson.
"The difficulty with hydrogen is that it's a very volatile gas. It likes tobe in gas form. It's very difficult to compress to sufficient density tobe stored onboard a vehicle or an airplane someday. As a result, thereis a pretty broad and diverse research effort nationwide and evenworldwide in trying to find some storage options."
But Yakobson thinks he's closer than ever to proving tinycarbon cages, known as buckyballs, can store highly-densevolumes of hydrogen. The research is only theoretical at thispoint, but using calculations, Yakobson has found the super-strong carbon cages, even at larger sizes, can hold enoughcondensed hydrogen to make them viable as possible energystorage devices.
"To be safe, I can tell you from the graphs and plots which weincluded in this report, you can see that even if you go downto one-quarter of the failure limit, you still have pretty gooddensity of hydrogen and good fraction between amount of stored hydrogen and the weight of the cage."
While Yakobson and his colleagues have determined the buckyballs are strong enough to hold condensed hydrogen, they haven't figured-out yet how to get the gas inside the tiny carbon cages. He says there might be several options.
"You can open cage wall, open hole there, and then you canclose it again. It has been demonstrated. The question is ofcourse which remains, can you do it at high pressure, becauseafter you open it you have to put hydrogen inside and then doing second reaction may be difficult."
Another option Yakobson wants to try is to simply immerse thebuckyballs in hydrogen and see if they somehow absorb the gas. His research appears on the cover of the American ChemicalSociety's journal Nano Letters this month.