Raman scattering and room temperature ferromagnetism in Co-doped SrTiO3 particles

Raman scattering has been used to study the influence of cobalt, an effective dopant to obtain SrTiO3 magnetic oxide, on the lattice dynamics of SrTiO3. It is found that Co doping increases the lattice defects and induces a Raman vibration mode of 690 cm−1. On the other hand, the ferromagnetism dependence on the x and annealing temperature was clearly and coherently observed in SrTi1−xCoxO3 (x = 0, 0.01, 0.03 and 0.05) nanoparticles. It is found that the ferromagnetism of SrTi1−xCoxO3 nanoparticles is weakly related to crystal deformation and oxygen vacancies in SrTiO3. So, F-center model can explain the origin of the ferromagnetism in the prepared Co-doped SrTiO3 samples. At the same time, the finding of large room-temperature ferromagnetism (1.6 emu/g) in this system would stimulate further interest in the area of more complicated ternary oxides.