Enhanced L1_0 chemical ordering and FePt/Fe_3O_4 core/shell structure formation in Zn-doped FePt nanoparticles

摘要

FePt nanoparticles doped with ～12 at. % Zn were successfully synthesized using the polyol and thermolysis methods. Their chemical ordering to the face-centered tetragonal (L1_0) phase was found to occur at a remarkably reduced temperature of ～324℃. The nanoparticles annealed at 400℃ for 60 min were identified to be in a highly crystalline L1_0 phase, showing formation of the distinct FePt/Fe_3O_4 core/shell structure. Also, they demonstrated strong ferromagnetic characteristics due to the high crystallinity with the L1_0 phase and the exchange coupling between the FePt core and the Fe_3O_4 shell.