Carbon dioxide laser synthesis from gaseous precursors has been successfully applied to produce nanosized Al₂O₃ particles. Trimethylaluminum [Al(CH₃)₃] and nitrous-oxide (N ₂O) were used as gas phase reactants. Ethylene (C₂H ₄) was added as sensitizer gas. The as-synthesized powder particles showed considerable carbon contamination and an amorphouslike structure. After thermal treatment at 1200-1400°C, the powder transformed to hexagonal α-Al₂O₃ with very low carbon contamination, confirmed by x-ray diffraction, x-ray photoelectron spectroscopy, and chemical analysis. The thermally treated powder was composed of spherical single-crystal nanoparticles with a mean size 〈D〉 of 15-20 nm, as determined by x-ray diffraction, electron microscopy, and Brunauer-Emmett-Teller specific surface measurements. The laser synthesized Al₂O₃ particles are suitable dispersoids for intermetallic alloy technology.

Cited By (since 1996): 27Export Date: 1 September 2010Source: Scopus