Abstract: Ultrafine powder of α-Fe₂O₃ doped with antimony has been prepared by a novel oxidation coprecipitation method. The products have been characterized by XRD, TEM, and their specific areas have been determined by front chromatography. The results showed that the powder prepared by this method has smaller mean particle size and larger specific area than that obtained by chemical coprecipitation. Ultrafine powder of α-Fe₂O₃ doped with Sn and Sb has also been prepared. The gas-sensitive ceramic units fabricated with powder prepared by the new method has been found to have much lower electrical resistance in air.

Key words: α-Fe₂O₃ ceramic, Sb-doped gas-sensitive material, nanometer-sized material