| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 1608528 | Journal of Alloys and Compounds | 2015 | 9 Pages |
•A systematic study was done on the effect of the substitution of Ti2+ and Ru4+ for Fe3+ in SrM.•Full structural refinement was carried out.•The magnetic properties were studied in a wide range of temp. and magnetic fields.•The saturation magnetization and the coercivity strongly depend on Ru–Ti substitution.•A clear understanding on the cationic distributions and magnetic behavior was obtained.
We carried out a systematic study on the effect of the substitution of Ti2+ and Ru4+ ions for Fe3+ ions on the structural and magnetic properties of the strontium ferrite SrFe12−2xRuxTixO19 nanoparticles with (0≤x≤0.30≤x≤0.3), using x-ray diffraction, Quantum Design PPMS-9 magnetometry, and electrical resistivity. A clear irreversibility between the zero-field-cooled and field-cooled curves was observed below room temperature and the zero-field-cooled magnetization curves displayed a broad peak at a temperature TM. These results were discussed within the framework of random particle assembly model and associated with the magnetic domain wall motion. The resistivity data showed some kind of a transition from insulator to perfect insulator around TMTM. The high-temperature magnetization measurements exhibited sharp peaks just below Tc indicating a superparamagnetic behavior. With Ru–Ti substitution, the saturation magnetization at 5 K showed small variations were it slightly increased with increasing x up to 0.2, and then decrease for x = 0.3, while the coercivity decreased monotonically, recording a reduction of about 78% at x = 0.3. These results were discussed in light of the cationic distributions based on the results of the structural refinements.
Graphical abstract(a) Zero-field-cooled and field-cooled magnetizations of SrFe12−2xRuxTixO19 as a function of temperature measured at 100 Oe for x = 0.3. (b) Thermomagnetic magnetizations measurements of SrFe12−2xRuxTixO19 with different concentrations. (c) Saturation magnetization and coercivity of SrFe12−2xRuxTixO19 as a function of Ru–Ti concentration (x). (d) Anisotropy field and the first anisotropy constant of SrFe12−2xRuxTixO19 as a function of Ru–Ti concentration (x).Figure optionsDownload full-size imageDownload as PowerPoint slide
