National Institute for Materials Science

Structural Stability of Hydrogen Storage Materials

Katagiri M., Onodera H., Ogawa H., National Institute for Materials Science, JP

Elastic instability by hydrogenation and hydrogen diffusion are studied by molecular dynamics method. The bulk modulus instability causes the anorphization by hydrogenation. The atomic relaxation reduces the pressure fluctuation terms i n the elastic constant, [...]

Computer Simulation of Hydrogen Storage Materials

Katagiri M., Onodera H., Ogawa H., National Institute for Materials Science, JP

We develope a new software to design the hydrogen storage materials. The energetic and dynamical behavior of the materials are studied. As an example, we illustrate the amorphization process of intermetallics by hydrogenation, i.e. hydrogen [...]

Growth of Nanostructured Diamond, Diamond-Like Carbon, and Carbon Nanotubes in a Low Pressure Inductively Coupled Plasma

Okada K., National Institute for Materials Science, JP

A 13.56 MHz low pressure inductively coupled CH4/CO/H2 plasma has been applied to prepare nanocrystalline diamond particles of 200-700 nm diameter. The minimum diameter of the particles was found to be 5 nm. Two-dimensional platelet-like [...]

TEM and Raman Spectroscopy Analyses of Fullerene Nanowhiskers and Nanotubes

Miyazawa K., Ringor C., Nakamura K., Nakamura S., Tachibana M., Mashino T., Nakamura K., Nakamura S., National Institute for Materials Science, JP

Structure of the nanowhiskers and nanotubes composed of C60 molecules and C60 derivative molecules are examined by use of Raman spectroscopy and transmission electron microscopy (TEM). The C60 nanotubes (C60NTs) dried in air exhibited a [...]

Improving the High Temperature Thermoelectric Properties of Boron Cluster Compounds through Microstructure Control

Mori T., Nishimura T., Bando Y., National Institute for Materials Science, JP

The search for thermoelectric materials is being carried out with great intensity because of the huge possibilities for useful energy conversion of waste heat. There is obviously a particular need to develop materials which can [...]

Novel Function of the Boron Icosahedron; a New Mediator of Magnetic Interaction

Mori T., National Institute for Materials Science, JP

Rare earth borides containing the B12 icosahedron display surprisingly strong magnetic interactions although they are magnetically dilute insulating materials with localized f-electrons. A microscopic local probe, ESR, was utilized to investigate the mechanism of the [...]