Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

A Noble yet Simple way to Synthesize New Metal-Free Electrocatalysts for Oxygen Reduction Reaction (ORR)

29.10.2013
A UNIST undergrad, Minju Park, and her research team found a new way to synthesize highly efficient electrocatalysts based on heteroatom-doped graphene nanosheets.

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 Reactionh)


Overall Scheme for doped graphene oxide
Copyright : UNIST

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 eNGOnf, which was chemically functionalized graphene oxide. NGOn suspensions were annealed at 800 Ž for 1h under an argon atmosphere with tube furnace, and nitrogen was doped into the graphene oxide nanosheets with removing oxygen named eNRGOnf.

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
Journal information
Nanoscale
Funding information
National Research Foundation of Korea (NRF)

Eunhee Song | Research asia research news
Further information:
http://www.unist.ac.kr
http://www.researchsea.com

More articles from Power and Electrical Engineering:

nachricht Waste from paper and pulp industry supplies raw material for development of new redox flow batteries
12.10.2017 | Johannes Gutenberg-Universität Mainz

nachricht Low-cost battery from waste graphite
11.10.2017 | Empa - Eidgenössische Materialprüfungs- und Forschungsanstalt

All articles from Power and Electrical Engineering >>>

The most recent press releases about innovation >>>

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

Im Focus: Salmonella as a tumour medication

HZI researchers developed a bacterial strain that can be used in cancer therapy

Salmonellae are dangerous pathogens that enter the body via contaminated food and can cause severe infections. But these bacteria are also known to target...

Im Focus: Neutron star merger directly observed for the first time

University of Maryland researchers contribute to historic detection of gravitational waves and light created by event

On August 17, 2017, at 12:41:04 UTC, scientists made the first direct observation of a merger between two neutron stars--the dense, collapsed cores that remain...

Im Focus: Breaking: the first light from two neutron stars merging

Seven new papers describe the first-ever detection of light from a gravitational wave source. The event, caused by two neutron stars colliding and merging together, was dubbed GW170817 because it sent ripples through space-time that reached Earth on 2017 August 17. Around the world, hundreds of excited astronomers mobilized quickly and were able to observe the event using numerous telescopes, providing a wealth of new data.

Previous detections of gravitational waves have all involved the merger of two black holes, a feat that won the 2017 Nobel Prize in Physics earlier this month....

Im Focus: Smart sensors for efficient processes

Material defects in end products can quickly result in failures in many areas of industry, and have a massive impact on the safe use of their products. This is why, in the field of quality assurance, intelligent, nondestructive sensor systems play a key role. They allow testing components and parts in a rapid and cost-efficient manner without destroying the actual product or changing its surface. Experts from the Fraunhofer IZFP in Saarbrücken will be presenting two exhibits at the Blechexpo in Stuttgart from 7–10 November 2017 that allow fast, reliable, and automated characterization of materials and detection of defects (Hall 5, Booth 5306).

When quality testing uses time-consuming destructive test methods, it can result in enormous costs due to damaging or destroying the products. And given that...

Im Focus: Cold molecules on collision course

Using a new cooling technique MPQ scientists succeed at observing collisions in a dense beam of cold and slow dipolar molecules.

How do chemical reactions proceed at extremely low temperatures? The answer requires the investigation of molecular samples that are cold, dense, and slow at...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

3rd Symposium on Driving Simulation

23.10.2017 | Event News

ASEAN Member States discuss the future role of renewable energy

17.10.2017 | Event News

World Health Summit 2017: International experts set the course for the future of Global Health

10.10.2017 | Event News

 
Latest News

Flying: Efficiency thanks to Lightweight Air Nozzles

23.10.2017 | Materials Sciences

Salmonella as a tumour medication

23.10.2017 | Life Sciences

50th Anniversary at JULABO GmbH

23.10.2017 | Press release

VideoLinks
B2B-VideoLinks
More VideoLinks >>>