Mitsuo Iwase

Photoelectrolysis of water with TiO2‐covered solar‐cell electrodes

A TiO2–solar‐cell hybrid structure has been used successfully as the anode electrode in the photoelectrolysis of water. The TiO2 films have been fabricated by chemical vapor deposition. Conversion efficiency of solar energy of about 0.1% has been attained in the preliminary experiment.

Tetragonal germanium flims deposited by the cluster‐beam evaporation technique

Germanium (Ge) films have been fabricated by the cluster‐beam technique. In transmission electron microscope (TEM) micrographs, the film deposited on a substrate at room temperature appears smooth and uniform, while that deposited at liquid nitrogen temperature consists of nanostructures with diameters from 4 to 40 nm. The x‐ray diffraction (XRD) patterns show that the crystalline structure for either deposition temperature is not the ordinary diamond structure but is tetragonal. The absorption spectra are distinct from that of bulk Ge. The photo‐oxidized Ge nanostructures exhibit blue light emission, which is strong enough to be recognized with the naked eye even under a room light.