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 Open, flexible assembly platform for optical systems
23.01.2017 | Fraunhofer-Institut für Produktionstechnologie IPT

nachricht A big nano boost for solar cells
18.01.2017 | Kyoto University and Osaka Gas effort doubles current efficiencies

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: Quantum optical sensor for the first time tested in space – with a laser system from Berlin

For the first time ever, a cloud of ultra-cold atoms has been successfully created in space on board of a sounding rocket. The MAIUS mission demonstrates that quantum optical sensors can be operated even in harsh environments like space – a prerequi-site for finding answers to the most challenging questions of fundamental physics and an important innovation driver for everyday applications.

According to Albert Einstein's Equivalence Principle, all bodies are accelerated at the same rate by the Earth's gravity, regardless of their properties. This...

Im Focus: Traffic jam in empty space

New success for Konstanz physicists in studying the quantum vacuum

An important step towards a completely new experimental access to quantum physics has been made at University of Konstanz. The team of scientists headed by...

Im Focus: How gut bacteria can make us ill

HZI researchers decipher infection mechanisms of Yersinia and immune responses of the host

Yersiniae cause severe intestinal infections. Studies using Yersinia pseudotuberculosis as a model organism aim to elucidate the infection mechanisms of these...

Im Focus: Interfacial Superconductivity: Magnetic and superconducting order revealed simultaneously

Researchers from the University of Hamburg in Germany, in collaboration with colleagues from the University of Aarhus in Denmark, have synthesized a new superconducting material by growing a few layers of an antiferromagnetic transition-metal chalcogenide on a bismuth-based topological insulator, both being non-superconducting materials.

While superconductivity and magnetism are generally believed to be mutually exclusive, surprisingly, in this new material, superconducting correlations...

Im Focus: Studying fundamental particles in materials

Laser-driving of semimetals allows creating novel quasiparticle states within condensed matter systems and switching between different states on ultrafast time scales

Studying properties of fundamental particles in condensed matter systems is a promising approach to quantum field theory. Quasiparticles offer the opportunity...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Sustainable Water use in Agriculture in Eastern Europe and Central Asia

19.01.2017 | Event News

12V, 48V, high-voltage – trends in E/E automotive architecture

10.01.2017 | Event News

2nd Conference on Non-Textual Information on 10 and 11 May 2017 in Hannover

09.01.2017 | Event News

 
Latest News

Tracking movement of immune cells identifies key first steps in inflammatory arthritis

23.01.2017 | Health and Medicine

Electrocatalysis can advance green transition

23.01.2017 | Physics and Astronomy

New technology for mass-production of complex molded composite components

23.01.2017 | Process Engineering

VideoLinks
B2B-VideoLinks
More VideoLinks >>>