Abstract: Nanometer ferric oxide were prepared by sol-gel and supercritical fluid drying (SCFD) method. The nanometer ferric oxide powders were characterized in terms of XRD, and TEM techniques. The dependence of particle size on preparation conditions was also investigated. It was found that the drying and crystal can be achieved in one step by the SCFD technique.

Key words: supercritical fluid drying, gasgel, ferric oxide, ultrafine particle