Effect of Mn and Ni-doping on structure, photoluminescence and magnetic properties of perovskite-type BaSn_0.99Gd_0.01O₃

In this study, the effect of transition metal substitution on the structure and magnetic properties of BaSn_0.99Gd_0.01O₃ was investigated. Oxides with a chemical formula BaSn_0.99-xGd_0.01M_xO_3-δ (M = Mn, Ni, x = 1 and 4 at.%) were synthesized by citric acid-assisted combustion method. Powder X-ray diffraction has confirmed the formation of pure single-phase cubic structure for BaSn_0.99-xGd_0.01M_xO_3-δ. The photoluminescence spectrum of the un-doped BaSnO₃ displayed a strong near-infrared emission peak at 832 nm, which showed a decline in its intensity after the addition of Gd and virtually disappeared in Mn or Ni-doped BaSn_0.99Gd_0.01O₃. Temperature-dependent electrical conductivity measurements have demonstrated an improvement in conductivity of BaSnO₃ after simultaneous co-doping with Gd and Mn. A very weak ferromagnetic behavior was observed for the pure BaSnO₃ under a low magnetic field. In spite, a pronounced room temperature-ferromagnetic behavior was seen for all the doped BaSn_0.99-xGd_0.01M_xO_3-δ samples over the whole measuring range of magnetic field. Among the prepared samples, a notable enhancement in the magnetic parameters was shown upon doping BaSn_0.99Gd_0.01O₃ with Mn. The ferromagnetic behavior of the co-doped samples was discussed in terms of F-center exchange interaction mechanism.