| Abstract |
| Real-time formation of L10 phase of FePt nanoparticles in the gas phase during ultrasonic-spray pyrolysis is first discussed in the present study. Without any post heat treatment, L10 phase of FePt nanoparticles appeared at the temperature above 900℃ in the gas phase synthesis. X-ray diffractometry (XRD) and transmission electron microscopy (TEM) studies revealed that FePt nanoparticles less than 10 nm in size contained small volume of L10 fct phase. However, in other samples obtained at the temperature below 900℃, iron oxide phase co-existed and no evidence of phase transformation was found. Thus, it is anticipated that the time of flight of particles required for crystallization and phase transformation was extended according to the increase of the collision rate. Finally, magnetic properties represented by coercivity and saturation magnetization and functional groups on the particle surface were discussed based on VSM and FTIR results. |
|
|
| Key Words |
| real-time phase transformation, FePt nanoparticles, ultrasonic spray, metal acetylacetonates |
|
|
 |
|
