Effect of Bi and Sr doping on morphological and magnetic properties of LaCo0.6Fe0.4O3 nanosized perovskites

Abstract

Nanopowders of La 1−x Bi x Co0.6Fe0.4O3 (x = 0, 0.1, 0.2) and La 1−2x Bi x Sr x Co0.6Fe0.4O3 (x = 0.1) multinary perovskites were synthesized by citrate sol–gel autocombustion method. Crystalline phase and the lattice parameters were obtained from X-ray diffraction pattern. The XRD result shows that all compounds have rhombhohedral crystal structure with $\bar {\mathbf {R}\mathbf {3}}$ c space group and Bi (x = 0.2) have the presence of secondary peaks. Crystallite size, dislocation density, specific area and strain were calculated from XRD. The elemental composition and micrographs of grain were obtained from EDAX (energy dispersive X-ray analysis) and SEM (scanning electron microscopy), with an average grain size below 400 nm. Surface morphological studies using XPS (X-ray photoelectron spectroscopy) were used to find out the chemical states and surface proportion of oxygen present in samples. Finally, using the vibrating sample magnetometer the room temperature magnetic behaviour of compounds was studied and it was observed that the ferromagnetic behaviour of LaCo0.6Fe0.4O3 was reduced by Bi and Sr doping.