Nanotechnology Now

Our NanoNews Digest Sponsors





Heifer International

Wikipedia Affiliate Button


android tablet pc

Home > Press > New Catalyst for Safe, Reversible Hydrogen Storage: Room-temperature reaction takes place in water; can switch from hydrogen storage to release by changing pH

This diagram shows the new catalyst in its protonated and deprotonated states as it reversibly converts hydrogen and CO2 gas to and from liquid formate or formic acid at ambient temperature and pressure. The gases can thereby be stored and transported as a liquid, and used later in carbon-neutral energy applications, simply by adjusting the pH.
This diagram shows the new catalyst in its protonated and deprotonated states as it reversibly converts hydrogen and CO2 gas to and from liquid formate or formic acid at ambient temperature and pressure. The gases can thereby be stored and transported as a liquid, and used later in carbon-neutral energy applications, simply by adjusting the pH.

Abstract:
Scientists at the U.S. Department of Energy's (DOE) Brookhaven National Laboratory and collaborators have developed a new catalyst that reversibly converts hydrogen gas and carbon dioxide to a liquid under very mild conditions. The work - described in a paper published online March 18, 2012, in Nature Chemistry - could lead to efficient ways to safely store and transport hydrogen for use as an alternative fuel.

New Catalyst for Safe, Reversible Hydrogen Storage: Room-temperature reaction takes place in water; can switch from hydrogen storage to release by changing pH

Upton, NY | Posted on March 19th, 2012

Hydrogen is seen as an attractive fuel because it can efficiently be converted to energy without producing toxic products or greenhouse gases. However, the storage and transportation of hydrogen remain more problematic than for liquid hydrocarbon fuels. The new work builds on earlier efforts to combine hydrogen with carbon dioxide to produce a liquid formic acid solution that can be transported using the same kind of infrastructure used to transport gasoline and oil.

"This is not the first catalyst capable of carrying out this reaction, but it is the first to work at room temperature, in an aqueous (water) solution, under atmospheric pressure - and that is capable of running the reaction in forward or reverse directions depending on the acidity of the solution," said Brookhaven chemist Etsuko Fujita, who oversaw Brookhaven's contributions to this research.

"When the release of hydrogen is desired for use in fuel cells or other applications, one can simply flip the 'pH switch' on the catalyst to run the reaction in reverse," said Brookhaven chemist James Muckerman, a co-author on the study. He noted that the liquid formic acid might also be used directly in a formic-acid fuel cell.

Collaborator Yuichiro Himeda of the National Institute of Advanced Industrial Science and Technology (AIST) of Japan had been making substantial progress toward the goal of developing this type of catalyst for a number of years. He used iridium metal complexes containing aromatic diimine ligands (groups of atoms bound to the metal) with pendent, peripheral hydroxyl (OH) groups that can serve as acidic sites that release protons to become pendent bases.

Himeda recently entered into collaboration - via the U.S.-Japan Collaboration on Clean Energy Technology program - with Fujita, Muckerman, and Jonathan Hull (a Goldhaber Fellow working on Fujita's team). The Brookhaven group carried out coordinated experimental and theoretical studies to understand the sequence of chemical steps by which these catalysts converted H2 and CO2 into formic acid. Their goal was to design new catalysts with improved performance.

The Brookhaven team's key idea came from Nature: "We were inspired by the way hydrogen bonds and bases relay protons in the active sites of some enzymes," Hull said.

"Good catalysts efficiently move protons and electrons around, taking them from some molecules and placing them onto others to produce the desired product," he explained. "Nature has many ways of doing this. Under the right conditions, the hydroxyl groups on the diimine ligand of the catalyst help hydrogen react with carbon dioxide, which is difficult to do. We thought we could improve the reactivity by placing the pendent bases near the metal centers, rather than in peripheral positions."

Once the Brookhaven team understood how Himeda's catalysts worked, Hull realized that a novel ligand that had been synthesized by collaborators Brian Hashiguchi and Roy Periana of The Scripps Research Institute for an entirely different purpose would possibly be ideal for accomplishing this goal. The Brookhaven group designed a new iridium metal catalyst incorporating this new ligand.

Collaborator David Szalda of Baruch College (City University of New York) determined the atomic level crystal structure of the new catalyst to "see" how the arrangement of its atoms might explain its function.

Tests of the new catalyst revealed superior catalytic performance for storing and releasing H2 under very mild reaction conditions. For the reaction combining CO2 with H2, the scientists observed high turnovers at room temperature and ambient pressure; for the catalytic decomposition of formic acid to release hydrogen, the catalytic rate was faster than any previous report.

"We were able to convert a 1:1 mixture of H2 and CO2 to formate (the deprotonated form of formic acid) at room temperature, successfully regenerate H2, and then repeat the cycle. It's a design principle we are very fortunate to have found," said Hull.

The regenerated high-pressure gas mixture (hydrogen and carbon dioxide) is quite pure; importantly, no carbon monoxide (CO) - an impurity that can 'poison' fuel cells and thus reduce their lifetime - was detected. Therefore, this method of storing and regenerating hydrogen might have a use in hydrogen fuel cells.

Further efforts to optimize the hydrogen storage process are ongoing using several catalysts with the same design principle.

"This is a wonderful example of how fundamental research can lead to the understanding and control of factors that contribute to the solution of technologically important problems," Muckerman concluded.

This research was funded by the DOE Office of Science, a Goldhaber Distinguished Fellowship, and by the Japanese Ministry of Economy, Trade, and Industry.

DOE's Office of Science is the single largest supporter of basic research in the physical sciences in the United States, and is working to address some of the most pressing challenges of our time. For more information, please visit science.energy.gov.

####

About Brookhaven National Laboratory
One of ten national laboratories overseen and primarily funded by the Office of Science of the U.S. Department of Energy (DOE), Brookhaven National Laboratory conducts research in the physical, biomedical, and environmental sciences, as well as in energy technologies and national security. Brookhaven Lab also builds and operates major scientific facilities available to university, industry and government researchers. Brookhaven is operated and managed for DOE's Office of Science by Brookhaven Science Associates, a limited-liability company founded by the Research Foundation of State University of New York on behalf of Stony Brook University, the largest academic user of Laboratory facilities, and Battelle, a nonprofit, applied science and technology organization.

For more information, please click here

Contacts:
Karen McNulty Walsh

(631) 344-8350
or
Peter Genzer

(631) 344-3174

Copyright © Brookhaven National Laboratory

If you have a comment, please Contact us.

Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.

Bookmark:
Delicious Digg Newsvine Google Yahoo Reddit Magnoliacom Furl Facebook

Related Links

Scientific Paper: “Reversible hydrogen storage using CO2 and a proton-switchable iridium catalyst in aqueous media under mild temperatures and pressures”:

Profile of Jonathan Hull

Related News Press

News and information

East China University of Science and Technology Purchases Nanonex Advanced Nanoimprint Tool NX-B200 July 30th, 2014

Watching Schrödinger's cat die (or come to life): Steering quantum evolution & using probes to conduct continuous error correction in quantum computers July 30th, 2014

From Narrow to Broad July 30th, 2014

FLAG-ERA and TNT2014 join efforts: Graphene Networking at its higher level in Barcelona: Encourage the participation in a joint transnational call July 30th, 2014

Chemistry

Nature inspires a greener way to make colorful plastics July 30th, 2014

Tough foam from tiny sheets: Rice University lab uses atom-thick materials to make ultralight foam July 29th, 2014

Iranian Scientists Use Waste Cotton Fibers to Produce Cellulose Nanoparticles July 29th, 2014

Oregon chemists eye improved thin films with metal substitution: Solution-based inorganic process could drive more efficient electronics and solar devices July 21st, 2014

Laboratories

Stanford team achieves 'holy grail' of battery design: A stable lithium anode - Engineers use carbon nanospheres to protect lithium from the reactive and expansive problems that have restricted its use as an anode July 27th, 2014

NIST shows ultrasonically propelled nanorods spin dizzyingly fast July 22nd, 2014

Sono-Tek Corporation Announces New Clean Room Rated Laboratory Facility in China July 18th, 2014

Govt.-Legislation/Regulation/Funding/Policy

New imaging agent provides better picture of the gut July 30th, 2014

Watching Schrödinger's cat die (or come to life): Steering quantum evolution & using probes to conduct continuous error correction in quantum computers July 30th, 2014

Nature inspires a greener way to make colorful plastics July 30th, 2014

Tough foam from tiny sheets: Rice University lab uses atom-thick materials to make ultralight foam July 29th, 2014

Discoveries

New imaging agent provides better picture of the gut July 30th, 2014

Watching Schrödinger's cat die (or come to life): Steering quantum evolution & using probes to conduct continuous error correction in quantum computers July 30th, 2014

From Narrow to Broad July 30th, 2014

A new way to make microstructured surfaces: Method can produce strong, lightweight materials with specific surface properties July 29th, 2014

Announcements

University of Manchester selects Anasys AFM-IR for coatings and corrosion research July 30th, 2014

Nature inspires a greener way to make colorful plastics July 30th, 2014

Analytical solutions from Malvern Instruments support University of Wisconsin-Milwaukee researchers in understanding environmental effects of nanomaterials July 30th, 2014

FEI Unveils New Solutions for Faster Time-to-Analysis in Metals Research July 30th, 2014

Energy

From Narrow to Broad July 30th, 2014

Oregon chemists eye improved thin films with metal substitution: Solution-based inorganic process could drive more efficient electronics and solar devices July 21st, 2014

Steam from the sun: New spongelike structure converts solar energy into steam July 21st, 2014

3-D nanostructure could benefit nanoelectronics, gas storage: Rice U. researchers predict functional advantages of 3-D boron nitride July 15th, 2014

NanoNews-Digest
The latest news from around the world, FREE



  Premium Products
NanoNews-Custom
Only the news you want to read!
 Learn More
NanoTech-Transfer
University Technology Transfer & Patents
 Learn More
NanoStrategies
Full-service, expert consulting
 Learn More














ASP
Nanotechnology Now Featured Books




NNN

The Hunger Project







© Copyright 1999-2014 7th Wave, Inc. All Rights Reserved PRIVACY POLICY :: CONTACT US :: STATS :: SITE MAP :: ADVERTISE