Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Large scale production of Edge-Functionalized Graphene Nanoplatelets (EFGnPs)

13.02.2013
Researchers from the Ulsan National Institute of Science and Technology (UNIST), South Korea have pioneered a simple, but efficient and eco-friendly way to produce Edge-selectively functionalized graphene nanoplatelets (EFGnPs) by dry ball milling graphite in the presence of various gases.
The electrocatalytic activity of heteroatom-doped carbon-based nanomaterials has become a growing interest in the past few years due to their potential applications for fuel cells and metal-air batteries.

Several approaches currently exist for the doping of heteroatoms into graphitic structure, but these suffer from high manufacturing costs and technical difficulties.
Researchers at Ulsan National Institute of Science and Technology (UNIST) have come up with a simple, but efficient and eco-friendly alternative which sees the production of edge-selectively functionalized graphene nanoplatelets (EFGnPs) via a dry ball milling graphite in the presence of various gases. The dry ball mill is effectively a type of grinder, traditionally use to grind ores, chemicals and other raw materials into fine powder. It can also be used on a atomic level, as is the case when producing EFGnPs.

Due to the versatility of mechanochemical reactions driven by ball milling, various functional groups could be introduced to the broken edges of graphene nanoplatelets (GnPs) in the presence of appropriate chemical vapors, liquids, or solids in the ball-mill crusher.

The mechanism of edge-selective functionalization in the ball-milling process involves the reaction between reactive carbon species generated by a mechanochemical cleavage of graphitic C-C bonds and gases in a sealed ball-mill crusher. The dormant active carbon species, which remain unreactive in the crusher, could be terminated by subsequent exposure to air moisture. As a result, some oxygenated groups, such as hydroxyl (-OH) and carboxylic acid (-COOH), can be introduced at the broken edges of the preformed EFGnPs with minimal basal plane distortion.

A scanning electron microscope (SEM) is used to demonstrate the mechanochemical cracking of a large grain sized piece of graphite into a small grain size of EFGnPs. Due to the reaction between the newly formed active carbon species at the broken edges of the GnPs and corresponding gases, the ball milling and subsequent workup procedures were found to increase the weight of all the resultant EFGnPs with respect to the graphite starting material. These results indicated that the mechanochemical functionalization of graphite was efficient. The resultant EFGnPs are active enough for the oxygen reduction reaction (ORR) in fuel cells, and hence they will make expensive platinum (Pt)-based electrocatalysts to take a back seat.

Jong-Beom Baek, professor and director of the Interdisciplinary School of Green Energy/Low-Dimensional Carbon Materials Center at UNIST commented:

“We have developed a simple, but versatile ball-milling process to efficiently exfoliate the pristine graphite directly into EFGnPs. Various microscopic and spectroscopic measurements were performed to confirm the reaction mechanisms for the edge functionalization of graphite by ball milling in the presence of corresponding gases and their superior slectrocatalytic activities of the ORR,” said Prof. Baek.

This research was funded by the Ministry of Education, Science and Technology (Minister Lee Ju-Ho) through the National Research Foundation of Korea (President Seung Jong Lee) and published in Journal of the American Chemical Society (Title: Large-scale production of edge-selectively functionalized graphene nanoplatelets via ball-milling and their use as metal-free electrocatalysts for oxygen reduction reaction).

REFERENCE:

In-Yup Jeon, Hyun-Jung Choi, Sun-Min Jung, Jeong-Min Seo, Min-Jung Kim, Liming Dai, and Jong-Beom Baek 2013. Large-scale production of edge-selectively functionalized graphene nanoplatelets via ball-milling and their use as metal-free electrocatalysts for oxygen reduction reaction" Journal of the American Chemical Society, 135(4): 1386–1393 (direct link below)

Journal information
Journal of American Chemical Society
Funding information
the Ministry of Education, Science and Technology (Minister Lee Ju-Ho) through the National Research Foundation of Korea (President Seung Jong Lee)

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

More articles from Materials Sciences:

nachricht Decoding cement's shape promises greener concrete
08.12.2016 | Rice University

nachricht Scientists track chemical and structural evolution of catalytic nanoparticles in 3-D
08.12.2016 | DOE/Brookhaven National Laboratory

All articles from Materials Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Electron highway inside crystal

Physicists of the University of Würzburg have made an astonishing discovery in a specific type of topological insulators. The effect is due to the structure of the materials used. The researchers have now published their work in the journal Science.

Topological insulators are currently the hot topic in physics according to the newspaper Neue Zürcher Zeitung. Only a few weeks ago, their importance was...

Im Focus: Significantly more productivity in USP lasers

In recent years, lasers with ultrashort pulses (USP) down to the femtosecond range have become established on an industrial scale. They could advance some applications with the much-lauded “cold ablation” – if that meant they would then achieve more throughput. A new generation of process engineering that will address this issue in particular will be discussed at the “4th UKP Workshop – Ultrafast Laser Technology” in April 2017.

Even back in the 1990s, scientists were comparing materials processing with nanosecond, picosecond and femtosesecond pulses. The result was surprising:...

Im Focus: Shape matters when light meets atom

Mapping the interaction of a single atom with a single photon may inform design of quantum devices

Have you ever wondered how you see the world? Vision is about photons of light, which are packets of energy, interacting with the atoms or molecules in what...

Im Focus: Novel silicon etching technique crafts 3-D gradient refractive index micro-optics

A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.

Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...

Im Focus: Quantum Particles Form Droplets

In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.

“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ICTM Conference 2017: Production technology for turbomachine manufacturing of the future

16.11.2016 | Event News

Innovation Day Laser Technology – Laser Additive Manufacturing

01.11.2016 | Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

 
Latest News

Researchers identify potentially druggable mutant p53 proteins that promote cancer growth

09.12.2016 | Life Sciences

Scientists produce a new roadmap for guiding development & conservation in the Amazon

09.12.2016 | Ecology, The Environment and Conservation

Satellites, airport visibility readings shed light on troops' exposure to air pollution

09.12.2016 | Health and Medicine

VideoLinks
B2B-VideoLinks
More VideoLinks >>>