SYNTHESIS OF ULTRAFINE NANOSIZE POWDERS OF IRON-OXIDES BY PULSED-LASER ABLATION AND COLD CONDENSATION/

Ultrafine/nanosize powders of iron oxide have been synthesized from a sintered alpha-Fe2O3 target by pulsed excimer laser ablation and cold condensation. The influence of target porosity and temperature of cond ensation on the formation of nanosize particles has been studied. The nanosize powders have been characterized by X-ray diffraction, Mossbau er spectroscopy, vibrating sample magnetometry and scanning electron m icroscopy. It is shown that the formation of ultrafine/nanosiae partic les is strongly governed by the target porosity, whereas, the temperat ure of condensation, over a range from 27 degrees C to -130 degrees C, does not affect the magnetic properties of the nanoparticles.