Now a team of chemical engineers at the University of Massachusetts Amherst has developed a computational model that shows that carbon nanotubes may offer a surprising solution. Results are presented in the current online issue of the journal, Applied Physics Letters.
“If this works as we expect, it’s perhaps no longer science fiction to hope for a briefcase-sized hydrogen battery to run a bus or car,” says UMass Amherst chemical engineering professor Dimitrios Maroudas. “Hydrogen storage has been a huge problem in the energy field for the past 10 years because no one has been able to demonstrate a truly viable storage medium. We’ve shown that it’s possible to achieve hydrogen storage capacity up to 8 percent by weight using carbon nanotubes. This is an outstanding level, higher by 1 percent than the 2010 United States Department of Energy target for on-board hydrogen storage systems,” Maroudas adds. “The method we propose may lead to breaking the bottleneck.”
The UMass Amherst computational model strongly lends itself to verification in laboratory experiments, say Maroudas and colleagues, and it provides ample testable hypotheses for future experimental research. “People had been losing faith, but I think our predictions show that hydrogen should be back on the table and in a most promising way. We come up with modeling predictions for technologically relevant problems every day, but this cute model is special,” he notes.
Specifically, Maroudas, his graduate student Andre Muniz and their collaborator M. Meyyappan, chief scientist for exploration technology at the Center for Nanotechnology at NASA Ames Research Center, Moffett Field, Calif., show that proper arrangement of carbon nanotubes can overcome hydrogen transport limitations in nanotube bundles. It should also prevent ineffective and nonuniform hydrogenation, which is caused by nanotube swelling due to chemisorption of hydrogen atoms on the nanotube walls.
If one were to think of carbon nanotube bundles as something like a toothbrush, one strategy that Maroudas and colleagues recommend for holding hydrogen atoms most efficiently is that the brush arrangement should not be too dense. If it is, when the tubules swell they’ll block efficient passage and diffusion of the hydrogen, Maroudas explains. In addition to an optimal bundle density, further improvement can be achieved by optimizing the individual nanotube configurations to limit their swelling upon hydrogenation.
Following this approach should result in one hydrogen atom being able to chemisorb onto — form a chemical bond with — each carbon atom of the nanotubes, leading to 100 percent (atomically) storage capacity, he adds. This chemisorbed hydrogen, bound to the surface, can then be easily released by applying heat.
Maroudas says, “We propose recipes that will be very easy for others to try, by which carbon nanotubes can be arranged to accomplish practically 100 percent storage atomically, which is nearly 8 percent by weight. You can’t get any greener than hydrogen as fuel, and if the experiments we envision lead to new technology that’s economically viable, that’s as good as it gets.” This work was supported by a National Science Foundation grant and a Fulbright/CAPES scholarship to Muniz.
Dimitrios Maroudas | Newswise Science News
Nano-scale process may speed arrival of cheaper hi-tech products
09.11.2018 | University of Edinburgh
Nuclear fusion: wrestling with burning questions on the control of 'burning plasmas'
25.10.2018 | Lehigh University
Researchers at the University of New Hampshire have captured a difficult-to-view singular event involving "magnetic reconnection"--the process by which sparse particles and energy around Earth collide producing a quick but mighty explosion--in the Earth's magnetotail, the magnetic environment that trails behind the planet.
Magnetic reconnection has remained a bit of a mystery to scientists. They know it exists and have documented the effects that the energy explosions can...
Biochips have been developed at TU Wien (Vienna), on which tissue can be produced and examined. This allows supplying the tissue with different substances in a very controlled way.
Cultivating human cells in the Petri dish is not a big challenge today. Producing artificial tissue, however, permeated by fine blood vessels, is a much more...
Faster and secure data communication: This is the goal of a new joint project involving physicists from the University of Würzburg. The German Federal Ministry of Education and Research funds the project with 14.8 million euro.
In our digital world data security and secure communication are becoming more and more important. Quantum communication is a promising approach to achieve...
On Saturday, 10 November 2018, the research icebreaker Polarstern will leave its homeport of Bremerhaven, bound for Cape Town, South Africa.
When choosing materials to make something, trade-offs need to be made between a host of properties, such as thickness, stiffness and weight. Depending on the application in question, finding just the right balance is the difference between success and failure
Now, a team of Penn Engineers has demonstrated a new material they call "nanocardboard," an ultrathin equivalent of corrugated paper cardboard. A square...
09.11.2018 | Event News
06.11.2018 | Event News
23.10.2018 | Event News
16.11.2018 | Health and Medicine
16.11.2018 | Life Sciences
16.11.2018 | Life Sciences