Forum für Wissenschaft, Industrie und Wirtschaft

Hauptsponsoren:     3M 
Datenbankrecherche:

 

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 Graphene origami as a mechanically tunable plasmonic structure for infrared detection
25.04.2018 | University of Illinois College of Engineering

nachricht Scientists create innovative new 'green' concrete using graphene
24.04.2018 | University of Exeter

All articles from Materials Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Why we need erasable MRI scans

New technology could allow an MRI contrast agent to 'blink off,' helping doctors diagnose disease

Magnetic resonance imaging, or MRI, is a widely used medical tool for taking pictures of the insides of our body. One way to make MRI scans easier to read is...

Im Focus: Fraunhofer ISE und teamtechnik bringen leitfähiges Kleben für Siliciumsolarzellen zu Industriereife

Das Kleben der Zellverbinder von Hocheffizienz-Solarzellen im industriellen Maßstab ist laut dem Fraunhofer-Institut für Solare Energiesysteme ISE und dem Anlagenhersteller teamtechnik marktreif. Als Ergebnis des gemeinsamen Forschungsprojekts »KleVer« ist die Klebetechnologie inzwischen so weit ausgereift, dass sie als alternative Verschaltungstechnologie zum weit verbreiteten Weichlöten angewendet werden kann. Durch die im Vergleich zum Löten wesentlich niedrigeren Prozesstemperaturen können vor allem temperatursensitive Hocheffizienzzellen schonend und materialsparend verschaltet werden.

Dabei ist der Durchsatz in der industriellen Produktion nur geringfügig niedriger als beim Verlöten der Zellen. Die Zuverlässigkeit der Klebeverbindung wurde...

Im Focus: BAM@Hannover Messe: Innovatives 3D-Druckverfahren für die Raumfahrt

Auf der Hannover Messe 2018 präsentiert die Bundesanstalt für Materialforschung und -prüfung (BAM), wie Astronauten in Zukunft Werkzeug oder Ersatzteile per 3D-Druck in der Schwerelosigkeit selbst herstellen können. So können Gewicht und damit auch Transportkosten für Weltraummissionen deutlich reduziert werden. Besucherinnen und Besucher können das innovative additive Fertigungsverfahren auf der Messe live erleben.

Pulverbasierte additive Fertigung unter Schwerelosigkeit heißt das Projekt, bei dem ein Bauteil durch Aufbringen von Pulverschichten und selektivem...

Im Focus: BAM@Hannover Messe: innovative 3D printing method for space flight

At the Hannover Messe 2018, the Bundesanstalt für Materialforschung und-prüfung (BAM) will show how, in the future, astronauts could produce their own tools or spare parts in zero gravity using 3D printing. This will reduce, weight and transport costs for space missions. Visitors can experience the innovative additive manufacturing process live at the fair.

Powder-based additive manufacturing in zero gravity is the name of the project in which a component is produced by applying metallic powder layers and then...

Im Focus: IWS-Ingenieure formen moderne Alu-Bauteile für zukünftige Flugzeuge

Mit Unterdruck zum Leichtbau-Flugzeug

Ingenieure des Fraunhofer-Instituts für Werkstoff- und Strahltechnik (IWS) in Dresden haben in Kooperation mit Industriepartnern ein innovatives Verfahren...

Alle Focus-News des Innovations-reports >>>

Anzeige

Anzeige

VideoLinks
Industrie & Wirtschaft
Veranstaltungen

Konferenz »Encoding Cultures. Leben mit intelligenten Maschinen« | 27. & 28.04.2018 ZKM | Karlsruhe

26.04.2018 | Veranstaltungen

Konferenz zur Marktentwicklung von Gigabitnetzen in Deutschland

26.04.2018 | Veranstaltungen

infernum-Tag 2018: Digitalisierung und Nachhaltigkeit

24.04.2018 | Veranstaltungen

VideoLinks
Wissenschaft & Forschung
Weitere VideoLinks im Überblick >>>
 
Aktuelle Beiträge

Weltrekord an der Uni Paderborn: Optische Datenübertragung mit 128 Gigabits pro Sekunde

26.04.2018 | Informationstechnologie

Multifunktionaler Mikroschwimmer transportiert Fracht und zerstört sich selbst

26.04.2018 | Biowissenschaften Chemie

Berner Mars-Kamera liefert erste farbige Bilder vom Mars

26.04.2018 | Physik Astronomie

Weitere B2B-VideoLinks
IHR
JOB & KARRIERE
SERVICE
im innovations-report
in Kooperation mit academics