Nanotechnology Now

Our NanoNews Digest Sponsors

Heifer International

Wikipedia Affiliate Button

Home > Press > Nanocrystal Catalyst Transforms Impure Hydrogen into Electricity: Brookhaven Lab scientists use simple, 'green' process to create novel core-shell catalyst that tolerates carbon monoxide in fuel cells and opens new, inexpensive pathways for zero-emission vehicles

Click on the image to download a high-resolution version. Computational model optimized with Density Functional Theory superimposed over a high-resolution scanning transmission electron microscopy (STEM) image (white dots). Ruthenium retains its structure with ABAB stacking sequence (blue dots) in the core, and the platinum shell switches to the distinct ABCABC stacking sequence.
Click on the image to download a high-resolution version. Computational model optimized with Density Functional Theory superimposed over a high-resolution scanning transmission electron microscopy (STEM) image (white dots). Ruthenium retains its structure with ABAB stacking sequence (blue dots) in the core, and the platinum shell switches to the distinct ABCABC stacking sequence.

Abstract:
The quest to harness hydrogen as the clean-burning fuel of the future demands the perfect catalysts-nanoscale machines that enhance chemical reactions. Scientists must tweak atomic structures to achieve an optimum balance of reactivity, durability, and industrial-scale synthesis. In an emerging catalysis frontier, scientists also seek nanoparticles tolerant to carbon monoxide, a poisoning impurity in hydrogen derived from natural gas. This impure fuel-40 percent less expensive than the pure hydrogen produced from water-remains largely untapped.

Nanocrystal Catalyst Transforms Impure Hydrogen into Electricity: Brookhaven Lab scientists use simple, 'green' process to create novel core-shell catalyst that tolerates carbon monoxide in fuel cells and opens new, inexpensive pathways for zero-emission vehicles

Upton, NY | Posted on September 18th, 2013

Now, scientists at the U.S. Department of Energy's (DOE) Brookhaven National Laboratory-in research published online September 18, 2013 in the journal Nature Communications-have created a high-performing nanocatalyst that meets all these demands. The novel core-shell structure-ruthenium coated with platinum-resists damage from carbon monoxide as it drives the energetic reactions central to electric vehicle fuel cells and similar technologies.

"These nanoparticles exhibit perfect atomic ordering in both the ruthenium and platinum, overcoming structural defects that previously crippled carbon monoxide-tolerant catalysts," said study coauthor and Brookhaven Lab chemist Jia Wang. "Our highly scalable, 'green' synthesis method, as revealed by atomic-scale imaging techniques, opens new and exciting possibilities for catalysis and sustainability."

Fabricating Crystals with Atomic Perfection

Catalysts inside fuel cells pry free the intrinsic energy of hydrogen molecules and convert it into electricity. Platinum performs exceptionally well with pure hydrogen fuel, but the high cost and rarity of the metal impedes its widespread deployment. By coating less expensive metals with thin layers of platinum atoms, however, scientists can retain reactivity while driving down costs and creating core-shell structures with superior performance parameters.

The carbon monoxide impurities in hydrogen formed from natural gas present another challenge to scientists because they deactivate most platinum catalysts. Ruthenium-less expensive than platinum-promotes carbon monoxide tolerance, but is more prone to dissolution during fuel cells' startup/shutdowns, causing gradual performance decay.

"We set out to protect ruthenium cores from dissolution with complete platinum shells just one or two atoms thick," Wang said. "Previous surface science studies revealed remarkable variation of surface properties in this core-shell configuration, suggesting the need and the opportunity to perfect the recipe with precise control."

Doubts existed about whether or not a highly ordered ruthenium core was even possible with a platinum shell-previously synthesized nanoparticles exhibited a weakened crystal structure in the ruthenium.

"Luckily, we found that the loss of ruthenium structure was due to defect-mediated interlayer diffusion, which is avoidable," Wang said. "By eliminating any lattice defects in ruthenium nanoparticles before adding platinum, we preserved the crucial, discrete atomic structure of each element."

The scalable and inexpensive synthesis method uses ethanol-a common and inexpensive solvent-as the reductant to fabricate the nanoparticle core and shell. The sophisticated process requires no other organic agents or metal templates.

"Simply adjusting temperature, water, and acidity of the solutions gave us complete control over the process and yielded remarkably consistent ruthenium nanoparticle size and uniform platinum coating," said Brookhaven Lab chemist Radoslav Adzic, another coauthor on the study. "This simplicity offers high reproducibility and scalability, and it demonstrates the clear commercial potential of our method."

Core-Shell Characterization

"We took the completed catalysts to other facilities here at the Lab to reveal the exact details of the atomic structure," Wang said. "This kind of rapid collaboration is only possible when you work right next door to world-class experts and instruments."

Scientists at Brookhaven Lab's National Synchrotron Light Source (NSLS) revealed the atomic density, distribution, and uniformity of the metals in the nanocatalysts using a technique called x-ray diffraction, where high-frequency light scatters and bends after interacting with individual atoms. The collaboration also used a scanning transmission electron microscope (STEM) at Brookhaven's Center for Functional Nanomaterials (CFN) to pinpoint the different sub-nanometer atomic patterns. With this instrument, a focused beam of electrons bombarded the particles, creating a map of both the core and shell structures.

"We found that the elements did not mix at the core-shell boundary, which is a critical stride," said CFN physicist Dong Su, coauthor and STEM specialist. "The atomic ordering in each element, coupled with the right theoretical models, tells us about how and why the new nanocatalyst works its magic."

Determining the ideal functional configuration for the core and shell also required the use of the CFN's expertise in computational science. With density functional theory (DFT) calculations, the computer helps identify the most energetically stable platinum-ruthenium structure.

"The DFT analysis connects the dots between performance and configuration, and it corroborates our direct observations from x-ray diffraction and electron microscopy," Adzic said.

Discovery to Deployment

Ballard Power Systems, a company dedicated to fuel cells production, independently evaluated the performance of the new core-shell nanocatalysts. Beyond testing the low-platinum catalysts' high activity in pure hydrogen, Ballard looked specifically at the resistance to carbon monoxide present in impure hydrogen gas and the dissolution resistance during startup/shutdown cycles. The bilayer nanocatalyst exhibited high durability and enhanced carbon monoxide tolerance-the combination enables the use of impure hydrogen without much loss in efficiency or increase in catalyst cost.

The nanocatalyst also performed well in producing hydrogen gas through the hydrogen evolution reaction, leading to another industrial partnership. Proton Onsite, a company specializing in splitting hydrogen from water and other similar processes, has completed feasibility tests for deploying the technology in their production of water electrolyzers, which will now require about 98 percent less platinum.

"Water electrolyzers are already on the market, so this nanocatalyst can deploy quickly," Wang said. "When hydrogen fuel cell vehicles roll out in the coming years, this new structure may accelerate development by driving down costs for both metal catalysts and fuel."

####

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 for the 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.

The Center for Functional Nanomaterials at Brookhaven National Laboratory is one of the five DOE Nanoscale Science Research Centers (NSRCs), premier national user facilities for interdisciplinary research at the nanoscale. Together the NSRCs comprise a suite of complementary facilities that provide researchers with state-of-the-art capabilities to fabricate, process, characterize and model nanoscale materials, and constitute the largest infrastructure investment of the National Nanotechnology Initiative. The NSRCs are located at DOE's Argonne, Brookhaven, Lawrence Berkeley, Oak Ridge and Sandia and Los Alamos national laboratories. For more information about the DOE NSRCs, please visit http://nano.energy.gov.

The National Synchrotron Light Source (NSLS) provides intense beams of infrared, ultraviolet, and x-ray light for basic and applied research in physics, chemistry, medicine, geophysics, and environmental and materials sciences. Supported by the Office of Basic Energy Sciences within the U.S. Department of Energy, the NSLS is one of the world's most widely used scientific facilities. For more information, visit www.nsls.bnl.gov.

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.

For more information, please click here

Contacts:
Justin Eure
(631) 344-2347

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: Ordered bilayer ruthenium-platinum core-shell nanoparticles as carbon monoxide-tolerant fuel cell catalysts:

Related News Press

News and information

ICN2 researchers compute unprecedented values for spin lifetime anisotropy in graphene November 17th, 2017

Math gets real in strong, lightweight structures: Rice University researchers use 3-D printers to turn century-old theory into complex schwarzites November 16th, 2017

The stacked color sensor: True colors meet minimization November 16th, 2017

Nanometrics to Participate in the 6th Annual NYC Investor Summit 2017 November 16th, 2017

Laboratories

Ames Laboratory, UConn discover superconductor with bounce October 25th, 2017

Nanotube fiber antennas as capable as copper: Rice University researchers show their flexible fibers work well but weigh much less October 23rd, 2017

Spin current detection in quantum materials unlocks potential for alternative electronics October 15th, 2017

Injecting electrons jolts 2-D structure into new atomic pattern: Berkeley Lab study is first to show potential of energy-efficient next-gen electronic memory October 13th, 2017

Discoveries

ICN2 researchers compute unprecedented values for spin lifetime anisotropy in graphene November 17th, 2017

Math gets real in strong, lightweight structures: Rice University researchers use 3-D printers to turn century-old theory into complex schwarzites November 16th, 2017

The stacked color sensor: True colors meet minimization November 16th, 2017

Counterfeits and product piracy can be prevented by security features, such as printed 3-D microstructures: Forgeries and product piracy are detrimental to society and industry -- 3-D microstructures can increase security -- KIT researchers develop innovative fluorescent 3-D stru November 15th, 2017

Announcements

ICN2 researchers compute unprecedented values for spin lifetime anisotropy in graphene November 17th, 2017

Math gets real in strong, lightweight structures: Rice University researchers use 3-D printers to turn century-old theory into complex schwarzites November 16th, 2017

The stacked color sensor: True colors meet minimization November 16th, 2017

Nanometrics to Participate in the 6th Annual NYC Investor Summit 2017 November 16th, 2017

Interviews/Book Reviews/Essays/Reports/Podcasts/Journals/White papers

ICN2 researchers compute unprecedented values for spin lifetime anisotropy in graphene November 17th, 2017

Math gets real in strong, lightweight structures: Rice University researchers use 3-D printers to turn century-old theory into complex schwarzites November 16th, 2017

The stacked color sensor: True colors meet minimization November 16th, 2017

Counterfeits and product piracy can be prevented by security features, such as printed 3-D microstructures: Forgeries and product piracy are detrimental to society and industry -- 3-D microstructures can increase security -- KIT researchers develop innovative fluorescent 3-D stru November 15th, 2017

Energy

Inorganic-organic halide perovskites for new photovoltaic technology November 6th, 2017

Dendritic fibrous nanosilica: all-in-one nanomaterial for energy, environment and health November 4th, 2017

New nanomaterial can extract hydrogen fuel from seawater: Hybrid material converts more sunlight and can weather seawater's harsh conditions October 4th, 2017

Researchers set time limit for ultrafast perovskite solar cells September 22nd, 2017

Automotive/Transportation

The next generation of power electronics? Gallium nitride doped with beryllium: How to cut down energy loss in power electronics? The right kind of doping November 9th, 2017

Leti Coordinating Project to Develop Innovative Drivetrains for 3rd-generation Electric Vehicles: CEA Tech’s Contribution Includes Liten’s Knowhow in Magnetic Materials and Simulation And Leti’s Expertise in Wide-bandgap Semiconductors October 20th, 2017

GLOBALFOUNDRIES Introduces New Automotive Platform to Fuel Tomorrow’s Connected Car: AutoPro™ provides a full range of technologies and manufacturing services to help carmakers harness the power of silicon for a new era of ‘connected intelligence’ October 12th, 2017

Organic/inorganic sulfur may be key for safe rechargeable lithium batteries October 12th, 2017

Fuel Cells

Hydrogen power moves a step closer: Physicists are developing methods of creating renewable fuel from water using quantum technology September 15th, 2017

More durable, less expensive fuel cells: University of Delaware researchers have developed a new technology that could speed up the commercialization of fuel cell vehicles September 5th, 2017

Engineers pioneer platinum shell formation process – and achieve first-ever observation August 11th, 2017

Argonne National Laboratory’s Continuous ALD Technology Licensed Exclusively to Forge Nano July 7th, 2017

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