Creation of new materials

Structure of nanotubes

In the early 1960, Feynman [24] has predicted that the future science and technology would be focused on miniaturisation, in which the electric motors would be designed as small as the size of the nail on your small finger. Every machine, structure and instrument would be designed starting from atomic scale. At that time, only physicists and chemists would interest in dealing with the works in such small scale. Until 1991, the discovery of nanotubes has revolutionised researches in many

Nanotubes composites

Since the discovery of nanotubes, extensive research in carbon, fullerence, nanosensor, nanoindentator and nanomachine has blossomed in many different directions, and has attracted a great deal of attention to advanced composite society. It is well understood that carbon fibres or nanotubes could not be utilised alone without any supporting medium, such as matrix to form structural components. Whereas, the investigation on the interfacial bonding properties between the nanotube and matrix

Other applications

Due to many unique properties of the nanotubes, the potentiality of its applications in real-life practice has been recently emerged. Dzegilenko et al. [66] have computed that nanotubes could be used as nanoetcher and nanoindentor to extract silicon atoms from the silicon surface robustly without additionally involving an externally applied voltage via molecular dynamic simulation. Avouris et al. [42] have demonstrated the use of a nanotube bundle as an electrode in nanoscale tip-induced
In research into nanotechnology of interest, Professor Shinohara and his colleagues have synthesized a metal nanowire using a carbon nanotube as a chemical reactor.
If you mix a carbon nanotube and fullerene, heat them to 500°C, and react for two days, fullerene molecules enter the nanotube (Fig. 3). This condition is similar to peas in a peapod, and because of this, the structure is called a peapod. Professor Shinohara thought that they could produce something new by combining the metal-containing fullerene (fullerene in which metal atoms are contained), which he has intensively studied, and the peapod, with the hope of discovering new materials in the nanometer world.
Professor Shinohara and his group created a peapod using fullerene molecules that contain gadolinium (Gd) atoms and heated it at a high temperature of 1200°C. This causes fullerene molecules to break and the Gd atoms are successfully ordered in the carbon nanotube. This indicates that a metal nanowire covered with a carbon nanotube can be created.
However, the wire was fragmented in the carbon nanotube because the metal filling rate is insufficient in the method using metal-containing fullerene. He innovatively placed carbon nanotubes and erbium chrolide (ErCl₃), instead of fullerene, in a test tube and heated them in vacuum at 800°C for three days. He hypothesized that ErCl₃ molecules were closely packed in the carbon nanotube and formed a wire by electron microscopy (Fig. 4).
To demonstrate that the wire materials are actually ErCl₃, X-ray analysis was required. General laboratories, however, have no equipment that can generate a high energy to observe the inner structure of the nanotube. Professor Shinohara sent Associate Professor Kitaura and graduate students, Daisuke Ogawa and Naoki Imazu, to SPring-8. They carried out experiments using the beamline for soft X-ray spectroscopy of solids (BL25SU) in a joint research with Tetsuya Nakamura, the senior scientist at JASRI, and Tsuyoshi Saito, the team leader at the National Institute of Advanced Industrial Science and Technology.