title: Crystallization behavior of iron-based amorphous nanoparticles prepared sonochemically.
abstract: In general, a rapid quenching is required to obtain an amorphous metal. It is known that an intensive ultrasonication generates a very high temperature within cavitation bubbles in a very short moment, which enables a rapid quenching process in a liquid phase synthesis. In this study, the sonochemically-derived "amorphous iron" from Fe(CO)5was carefully examined by XRD, TEM, TG-DTA. The product was found to be an amorphous containing a certain amount (∼15%) of volatile component that can be removed by heating in a nitrogen flow. After annealed in the inert atmosphere at 600°C, cooled down to room temperature, and then exposed in air (oxygen), the sample showed a strong exotherm accompanied by a weight gain. This is due to oxidation of fine metallic iron. Experimental operations of such a reactive material were examined.
authors.affiliation: Department of Applied Chemistry, Faculty of Engineering, Kyushu University, Japan. Electronic address: enomoto@cstf.kyushu-u.ac.jp.
authors.forename: Naoya
authors.initials: N
authors.lastname: Enomoto
authors.affiliation: Department of Applied Chemistry, Faculty of Engineering, Kyushu University, Japan.
authors.forename: Shingo
authors.initials: S
authors.lastname: Hirata
authors.affiliation: Department of Applied Chemistry, Faculty of Engineering, Kyushu University, Japan.
authors.forename: Miki
authors.initials: M
authors.lastname: Inada
authors.affiliation: Department of Applied Chemistry, Faculty of Engineering, Kyushu University, Japan.
authors.forename: Katsuro
authors.initials: K
authors.lastname: Hayashi
keywords: Iron carbonyl; Rapid quenching; Sonochemical synthesis