Effect of Ti doping on the structural, morphological and magnetic properties of La0.7Ga0.3Fe1-xTixO3

Abstract Orthoferrites perovskites are an important family of materials in the field of nanotechnology, particularly for cathodes in solid oxide fuel cells. Doping these materials enables the enhancement and control of their properties. In this context, we studied the effect of Ti doping on different properties of the La0.7Ga0.3Fe1-xTixO3 (x = 0, 0.1, 0.2 and 0.3) lanthanum orthoferrites. X-Ray Diffraction (XRD) measurements proved the presence of two orthorhombic phases with Pbnm and Pnma space groups. SEM images corroborate the XRD results, clearly signaling the presence of two phases in these samples, with EDS analysis allowing the estimation of each phase fraction. FTIR and Raman spectroscopies allowed us to study the vibrational modes related with the La-O, Fe-O and Ti-O bonds. We note a shift towards higher wavenumber associated with the increase in Ti. Magnetic measurements showed a transition from antiferromagnetism to weak ferromagnetism with the introduction of Ti. The zero-field cooled (ZFC) and field cooled (FC) magnetization versus temperature curves do not superimpose, proving the heterogeneity of the magnetic properties of the samples. The saturation magnetization Ms, the remanent magnetization Mr and the coercive field Hc decrease with both increasing temperature and Ti content.