Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Nano-cages ’fill up’ with hydrogen

02.12.2005


A "cagey" strategy to stack more hydrogen in nanoscale scaffoldings made of zinc-based boxes may yield a viable approach to storing hydrogen and, ultimately, replacing fossil fuels in future automobiles, according to new results from National Institute of Standards and Technology (NIST) researchers.



Using beams of neutrons as probes, NIST scientists determined where hydrogen latches onto the lattice-like arrangement of zinc and oxygen clusters in a custom-made material known as a metal-organic framework, or MOF. Called MOF5, the particular nanoscale material studied by Taner Yildirim and Michael Hartman has four types of docking sites, including a "surprising" three-dimensional network of "nano-cages" that appears to form after other sites load up with hydrogen.

This finding, reported in Physical Review Letters,* suggests that MOF materials might be engineered to optimize both the storage of hydrogen and its release under normal vehicle operating conditions. It also suggests that MOFs might be used as templates for interlinking hydrogen nano-cages, creating materials with unusual properties due to a phenomenon known as quantum confinement. In a sense, this discovery is a bonus.


Yildirim and Hartman found that the two most stable sites in the scaffolding already offer considerable room for storing hydrogen, accounting for the interest MOFs already have attracted. Earlier studies reported that, at about –200 degrees Celsius, MOF5 could hold less than 2 percent of its weight in hydrogen.

The NIST research indicates ample room for improvement. At very low temperatures, hydrogen uptake approached 10 percent of the material’s weight. (The FreedomCar and Fuel Partnership involving the Department of Energy and the nation’s "Big 3" automakers has set a level of about 6 percent as a minimum capacity for economically viable hydrogen storage.) The bulk of the hydrogen was held in nanometer-scale cavities inside the box-like arrangements of zinc and oxygen clusters.

"Neutron diffraction measurements clearly show that the molecules are packed in a fashion similar to the way apples or oranges fill a bowl," Yildirim explains. The unexpected nano-cages introduce the potential for spillover capacity, so to speak.

Hydrogen storage levels of 10 percent are encouraging, but these results were achieved at impractically low temperatures. Yildirim and Hartman say they hope better understanding of how hydrogen molecules tether to MOFs will ultimately lead to improved materials suitable for practical applications.

Mark Bello | EurekAlert!
Further information:
http://www.nist.gov
http://www.ncnr.nist.gov/staff/taner/h2

More articles from Physics and Astronomy:

nachricht A better way to weigh millions of solitary stars
15.12.2017 | Vanderbilt University

nachricht A chip for environmental and health monitoring
15.12.2017 | Friedrich-Alexander-Universität Erlangen-Nürnberg

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: First-of-its-kind chemical oscillator offers new level of molecular control

DNA molecules that follow specific instructions could offer more precise molecular control of synthetic chemical systems, a discovery that opens the door for engineers to create molecular machines with new and complex behaviors.

Researchers have created chemical amplifiers and a chemical oscillator using a systematic method that has the potential to embed sophisticated circuit...

Im Focus: Long-lived storage of a photonic qubit for worldwide teleportation

MPQ scientists achieve long storage times for photonic quantum bits which break the lower bound for direct teleportation in a global quantum network.

Concerning the development of quantum memories for the realization of global quantum networks, scientists of the Quantum Dynamics Division led by Professor...

Im Focus: Electromagnetic water cloak eliminates drag and wake

Detailed calculations show water cloaks are feasible with today's technology

Researchers have developed a water cloaking concept based on electromagnetic forces that could eliminate an object's wake, greatly reducing its drag while...

Im Focus: Scientists channel graphene to understand filtration and ion transport into cells

Tiny pores at a cell's entryway act as miniature bouncers, letting in some electrically charged atoms--ions--but blocking others. Operating as exquisitely sensitive filters, these "ion channels" play a critical role in biological functions such as muscle contraction and the firing of brain cells.

To rapidly transport the right ions through the cell membrane, the tiny channels rely on a complex interplay between the ions and surrounding molecules,...

Im Focus: Towards data storage at the single molecule level

The miniaturization of the current technology of storage media is hindered by fundamental limits of quantum mechanics. A new approach consists in using so-called spin-crossover molecules as the smallest possible storage unit. Similar to normal hard drives, these special molecules can save information via their magnetic state. A research team from Kiel University has now managed to successfully place a new class of spin-crossover molecules onto a surface and to improve the molecule’s storage capacity. The storage density of conventional hard drives could therefore theoretically be increased by more than one hundred fold. The study has been published in the scientific journal Nano Letters.

Over the past few years, the building blocks of storage media have gotten ever smaller. But further miniaturization of the current technology is hindered by...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

See, understand and experience the work of the future

11.12.2017 | Event News

Innovative strategies to tackle parasitic worms

08.12.2017 | Event News

AKL’18: The opportunities and challenges of digitalization in the laser industry

07.12.2017 | Event News

 
Latest News

Engineers program tiny robots to move, think like insects

15.12.2017 | Power and Electrical Engineering

One in 5 materials chemistry papers may be wrong, study suggests

15.12.2017 | Materials Sciences

New antbird species discovered in Peru by LSU ornithologists

15.12.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>