Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Rolling out the nanotubes

27.07.2009
Nanoscale materials with well-defined shapes, such as one-dimensional hollow tubes, have attracted the interest of scientists seeking to utilize their unique properties.

Nanotubes have large inner and outer surface areas that are accessible to many smaller molecules, meaning they have the potential to be developed into new types of sensors and catalysts.

Efficient techniques to synthesize nanotubes, however, are uncommon. Now, Takuzo Aida and Takanori Fukushima of the RIKEN Advanced Science Institute in Wako and colleagues from the Japan Science and Technology Agency have developed a way to controllably self-assemble graphitic molecules and platinum metals into nanotubes with specific dimensions and structural features1.

Aida and his team used a molecule called hexabenzocoronene (HBC) as the base for their new nanotubes. Consisting of thirteen aromatic benzene rings interlocked into a large, flat cyclic structure that resembles graphite, HBC is normally used as a building block for liquid crystalline semiconductors.

In 2004, Aida, Fukushima, and colleagues discovered that by adding long hydrocarbon groups and polar chains called triethylene glycol to HBC, they could make the graphitic molecule into an amphiphile2—a surfactant that can be dissolved in organic solvents. Recrystallizing a solution of the HBC amphiphiles spontaneously produced new graphitic nanotubes.

In their latest work, the researchers incorporated platinum metals into their nanotubes structures. According to Fukushima, transition metals such as platinum can add useful catalytic, electronic, luminescent, and magnetic functionalities to the nanotubes.

In order to attach platinum metals to the nanotubes, the scientists added a molecule known as pyridine, a nitrogen-containing benzene ring, to the ends of the triethylene glycol chains on the HBC amphiphile.

“Pyridine is one of the simplest and most common molecules for binding transition metals,” explains Fukushima. “We thought it fit to use such a general binding molecule in our first attempt to functionalize the HBC nanotubes with transition metals.”

By heating a solution of the HBC amphiphiles with platinum metal ions, then allowing the mixture to cool to room temperature, the scientists observed spontaneous formation of new metal-ion-coated graphitic nanotubes. Altering the assembly conditions produced tubular assemblies with different diameters, lengths, and wall widths.

“Our nanotube can serve as a unique one-dimensional nano-scaffold with not only high structural integrity, but also with beneficial electronic properties such as energy and charge transport capabilities,” says Fukushima. “We expect that the combination of these two components might lead to unprecedented phenomenon and functions.”

Reference

1. Zhang, W., Jin, W., Fukushima, T., Ishii, N. & Aida, T. Metal-ion-coated graphitic nanotubes: controlled self-assembly of a pyridyl-appended gemini-shaped hexabenzocoronene amphiphile. Angewandte Chemie International Edition 121, 4841–4844 (2009).

2. Hill, J. P., Jin, W., Kosaka, A., Fukushima, T., Ichihara, H., Shimomura, T., Ito, K., Hashizume, T., Ishii, N. & Aida, T. Self-assembled hexa-peri-hexabenzocoronene graphitic nanotube. Science 304, 1481–1483 (2004).

The corresponding author for this highlight is based at the RIKEN Functional Soft Matter Engineering Team

Saeko Okada | Research asia research news
Further information:
http://www.rikenresearch.riken.jp/research/753/
http://www.researchsea.com

More articles from Life Sciences:

nachricht Nanoparticle Exposure Can Awaken Dormant Viruses in the Lungs
16.01.2017 | Helmholtz Zentrum München - Deutsches Forschungszentrum für Gesundheit und Umwelt

nachricht Cholera bacteria infect more effectively with a simple twist of shape
13.01.2017 | Princeton University

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Designing Architecture with Solar Building Envelopes

Among the general public, solar thermal energy is currently associated with dark blue, rectangular collectors on building roofs. Technologies are needed for aesthetically high quality architecture which offer the architect more room for manoeuvre when it comes to low- and plus-energy buildings. With the “ArKol” project, researchers at Fraunhofer ISE together with partners are currently developing two façade collectors for solar thermal energy generation, which permit a high degree of design flexibility: a strip collector for opaque façade sections and a solar thermal blind for transparent sections. The current state of the two developments will be presented at the BAU 2017 trade fair.

As part of the “ArKol – development of architecturally highly integrated façade collectors with heat pipes” project, Fraunhofer ISE together with its partners...

Im Focus: How to inflate a hardened concrete shell with a weight of 80 t

At TU Wien, an alternative for resource intensive formwork for the construction of concrete domes was developed. It is now used in a test dome for the Austrian Federal Railways Infrastructure (ÖBB Infrastruktur).

Concrete shells are efficient structures, but not very resource efficient. The formwork for the construction of concrete domes alone requires a high amount of...

Im Focus: Bacterial Pac Man molecule snaps at sugar

Many pathogens use certain sugar compounds from their host to help conceal themselves against the immune system. Scientists at the University of Bonn have now, in cooperation with researchers at the University of York in the United Kingdom, analyzed the dynamics of a bacterial molecule that is involved in this process. They demonstrate that the protein grabs onto the sugar molecule with a Pac Man-like chewing motion and holds it until it can be used. Their results could help design therapeutics that could make the protein poorer at grabbing and holding and hence compromise the pathogen in the host. The study has now been published in “Biophysical Journal”.

The cells of the mouth, nose and intestinal mucosa produce large quantities of a chemical called sialic acid. Many bacteria possess a special transport system...

Im Focus: Newly proposed reference datasets improve weather satellite data quality

UMD, NOAA collaboration demonstrates suitability of in-orbit datasets for weather satellite calibration

"Traffic and weather, together on the hour!" blasts your local radio station, while your smartphone knows the weather halfway across the world. A network of...

Im Focus: Repairing defects in fiber-reinforced plastics more efficiently

Fiber-reinforced plastics (FRP) are frequently used in the aeronautic and automobile industry. However, the repair of workpieces made of these composite materials is often less profitable than exchanging the part. In order to increase the lifetime of FRP parts and to make them more eco-efficient, the Laser Zentrum Hannover e.V. (LZH) and the Apodius GmbH want to combine a new measuring device for fiber layer orientation with an innovative laser-based repair process.

Defects in FRP pieces may be production or operation-related. Whether or not repair is cost-effective depends on the geometry of the defective area, the tools...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

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

Nothing will happen without batteries making it happen!

05.01.2017 | Event News

 
Latest News

Multiregional brain on a chip

16.01.2017 | Power and Electrical Engineering

New technology enables 5-D imaging in live animals, humans

16.01.2017 | Information Technology

Researchers develop environmentally friendly soy air filter

16.01.2017 | Power and Electrical Engineering

VideoLinks
B2B-VideoLinks
More VideoLinks >>>