A Korean research team from Ulsan National Institute of Science and Technology (UNIST), S. Korea, developed a high performance and stable metal-free electrocatalyst for ORR and the research work was published in a science journal, Nanoscale by the Royal Society of Chemistry (RSC). (Title: gCovalent Functionalization Based Heteroatom Doped Graphene Nanosheet as a Metal-Free Electrocatalysts for Oxygen Reduction Reactionh)
Limited availability of fossil fuel and increasing energy demands have stimulated intense research on energy conversion and storage systems. Fuel cells have received considerable attention among the many choices of energy storage systems, owing to their remarkable potential energy density and environmental issues.
Electrocatalysts for oxygen reduction are critical components that may dramatically enhance the performance of fuel cells, which are perceived to be the power for future electric vehicles. For more economical fuel cells, engineers need fast and efficient electrocatalysts which split hydrogen gas to make electricity.
The UNIST research team led by Prof. Byeong-Su Kim from the Interdisciplinary School of Green Energy, UNIST, presented a unique design and characterization of new heteroatom-doped graphene nanosheets prepared through the covalent functionalization of various small organic molecules with a subsequent thermal treatment. This work was proposed and carried out by undergraduate student Minju Park from the Interdisciplinary School of Green Energy, UNIST.
There are many available methods to prepare nitrogen-doped (N-doped) graphene. These approaches successfully introduce nitrogen atoms within the graphene framework. However, many of them require toxic gas precursors, and are unable to control the degree of doping and type of nitrogen functionality.
Herein the UNIST Research team presented a simple approach for chemical functionalization toward heteroatom-dope graphene nanosheets with small organic molecules for use as electrocatalysts for the oxygen reduction reaction.
Here is how the material has been prepared:
Graphite oxide powder was prepared from graphite powder with oxidation and exfoliated to give a brown dispersion of graphene oxide (GO) under ultra sonication. Graphene oxide nanosheets have various functional groups on the edge such as carboxylic (-COOH), hydroxyl (-OH), and epoxy (-C-O-C).
When the GO suspension reacted with amines in the presence of 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide (EDC), a water soluble carbodiimide was usually obtained as the hydrochloride, carboxylic group in GO reacted with amine and formed an amide group. The research team defined it as eNGOnf, which was chemically functionalized graphene oxide. NGOn suspensions were annealed at 800 for 1h under an argon atmosphere with tube furnace, and nitrogen was doped into the graphene oxide nanosheets with removing oxygen named eNRGOnf.
Further the UNIST research team demonstrated how the electrochemical performance can be improved by varying the degree and configurations of the nitrogen dopant. Further, they extended the approach toward the introduction of other heteroatoms, such as boron and sulfur, into the graphene nanosheet.
gNitrogen-doped graphene nanosheets showed superior stability compared to commercial Pt/C catalysts. This approach has also been successfully extended to other heteroatoms such as boron and sulfur on the graphene nanosheets,h said Minju Park.
gWe envision this study will offer opportunities and insights for further development of hybrid electrocatalysts,h said Prof. Kim, presenting future research possibilities.
This research work was supported by the National Research Foundation of Korea (NRF) grant.
For more information:
Ulsan National Institute of Science and Technology http://www.unist.ac.kr
Associate Professor Byeong-Su Kim, Interdisciplinary School of Green Energy, UNIST http://bskim19.unist.ac.kr
National Research Foundation of Korea (NRF)
Further Reports about: electric vehicle > Electrocatalysts > Fuel cells > graphene > graphene oxide > information technology > Metal-Free > organic molecule > reduction > small organic molecule > storage system > UNIST
More articles from Power and Electrical Engineering:
Harvesting Electricity: Triboelectric Generators Capture Wasted Power
10.12.2013 | Georgia Institute of Technology
Scientists discover quick recipe for producing hydrogen
09.12.2013 | Deep Carbon Observatory
A unique solar panel design made with a new ceramic material points the way to potentially providing sustainable power cheaper, more efficiently, and requiring less manufacturing time.
It also reaches a four-decade-old goal of discovering a bulk photovoltaic material that can harness energy from visible and infrared light, not just ultraviolet light.
Scaling up this new design from its tablet-size prototype to a full-size solar panel would be a large step toward making solar power affordable compared with ...
Atlantische Flohkrebse pflanzen sich jetzt auch in arktischen Gewässern fort
Biologen des Alfred-Wegener-Institutes, Helmholtz-Zentrum für Polar- und Meeresforschung (AWI), haben zum ersten Mal nachgewiesen, dass sich in den arktischen Gewässern westlich Spitzbergens auch Flohkrebse aus dem wärmeren Atlantik fortpflanzen.
Diese überraschende Entdeckung deute auf einen möglichen Wandel der arktischen Zooplankton-Gemeinschaft hin, berichten die Wissenschaftler und Wissenschaftlerinnen in der Fachzeitschrift Marine Ecology ...
The molecular architecture of three key proteins and their complexes reveals how plants fine-tune their immune response to pathogens
Plants rarely get sick in their natural environment. When the threat of infection arises, a quick decision is made about the necessary countermeasures. The course is set by a protein which forms complexes with its partner proteins for this purpose.
Jane Parker from the Max Planck Institute for Plant Breeding ...
Researchers studying speciation of butterfly orchids on the Azores have been startled to discover that the answer to a long-debated question "Do the islands support one species or two species?" is actually "three species".
Hochstetter's Butterfly-orchid, newly recognized following application of a battery of scientific techniques and reveling in a complex taxonomic history worthy of Sherlock Holmes, is arguably Europe's rarest orchid species. Under threat in its mountain-top retreat, the orchid urgently requires conservation recognition.
A lavishly illustrated publication, titled "Systematic revision of Platanthera in ...
Researchers from Brown University and the University of Hawaii have found some mineralogical surprises in the Moon's largest impact crater.
Data from the Moon Mineralogy Mapper that flew aboard India's Chandrayaan-1 lunar orbiter shows a diverse mineralogy in the subsurface of the giant South Pole Aitken basin.
The differing mineral signatures could be reflective of the minerals dredged up at the time of the giant impact 4 billion years ago, ...
12.12.2013 | Life Sciences
12.12.2013 | Earth Sciences
12.12.2013 | Studies and Analyses
11.12.2013 | Event News
10.12.2013 | Event News
05.12.2013 | Event News