Subject Number : S-16-MS-1024
Support Type : Common use (including technical support necessary for the training)
Proposal Title (English) : Magnetic Property of metal doped BiFeO3
Username (English) : Bashir Ahmmad Arima
Affiliation (English) : Yamagata University

1. Summary
Bulk and nanoparticles of Ba and Ti co-doped BiFeO3 were prepared by solid state reaction method and ultrasonication method, respectively. The magnetic and electric properties of bulk and nanoparticles were investigated and compared to each other. The field and temperature dependent magnetization measurements exhibited significant difference between the magnetic properties of the bulk materials and their corresponding nanoparticles. The leakage current density of the bulk materials was also found to suppress in the ultrasonically prepared nanoparticles compared to that of bulk counterparts.

2. Experimental
Magnetization measurements of magnetic Bi0.7Ba0.3Fe1−xTixO3 nanoparticles and its parent ceramic samples were carried out using a SQUID, (Quantum Design MPMS-XL7, USA) both at zero field cooled (ZFC) and field cooled (FC) processes.

3. Results and Discussion
The room temperature M-H loops of Bi0.7Ba0.3Fe1−xTixO3 (x = 0.00–0.20) bulk samples and their corresponding nanoparticles are shown in figures 1(a) and (b), respectively. The inset of figure 1(a) and 1(b) show the hysteresis loop of bulk and nanoparticle of undoped BiFeO3, respectively. The linear M-H curve of bulk undoped BiFeO3 demonstrates its antiferromagnetic nature. Unlike undoped bulk BiFeO3, the Ba doped Bi0.7Ba0.3FeO3 as well as Ba and Ti co-doped bulk Bi0.7Ba0.3Fe1−xTixO3 materials exhibit nearly ferromagnetic behavior with notable remanent magnetization and coercivity.
Surprisingly, in the case of nanoparticles, figure 1(b), we have observed a completely different magnetic behavior than that of bulk materials. The hysteresis loops of the synthesized nanoparticles is completely unsaturated with negligible coercivity, figure 1(b). The linear M-H curves of the synthesized nanoparticles reveal their antiferromagnetic nature rather than the nearly ferromagnetic characteristic of their bulk counterparts.

Fig. 1 M-H hysteresis loop of bulk and nanomaterials.

4. Acknowledgements
Nanotechnology Platform Program (Molecule and Material Synthesis) of MEXT, Japan.

5. Publication/Presentation
(1) B. Ahmmad, K. Kanomoata, et al. (J. Phys. D: Appl. Phys.), Vol. 49 (2016) p.p.265003.
(2) M. A. Basith (others 9), B. Ahmmad, (J. Alloys. Compd.) Vol. 694 (2017) pp. 792-799.
(3) B. Ahmmad, The 3rd International Conference on Advanced Composite Materials, 2017/01/04 (Invited) .