Preparation and physical properties of nanosized semiconducting CrSi2 powders

Nanosized chromium disilicide (CrSi2) powder was prepared by the are plasma method and a subsequent purification process. The as-prepared CrSi2 powder was characterized by X-ray powder diffraction and transmission electron mi croscopy. The crystal structure of the powder was also confirmed with infra red spectroscopy. The thermal stability of powders were investigated from r oom temperature to 1000 degrees C in air and in a helium atmosphere, indica ting that even in the nanosize region this disilicide powder was stable up to 720 degrees C in air. Analysis of its photovoltage spectra shows that th ere exist two direct interband transitions in nanosized CrSi2 grains at 0.7 82 and 1.148 eV, respectively. (C) 1999 Elsevier Science S.A. All rights re served.