Synthesis of La1−xSrxMO3 (M = Mn, Fe, Co, Ni) nanopowders by alanine-combustion technique

La1−xSrxMO3 (M = Mn, Fe, Co, Ni, x = 0–0.3) powders were obtained by solution combustion technique using metal nitrates and α-alanine. The as-prepared powders, resulted by the combustion reaction, were annealed at different temperatures to investigate the evolution of crystalline phases. For the strontium-doped lanthanum-based perovskites, higher annealing temperatures than for the corresponding pure lanthanum-based perovskites are needed to obtain single-phase compounds depending on M-site metal and strontium content. The oxide powders were investigated by FT-IR spectra, X-ray diffraction (XRD), scanning electron microscopy (SEM) and specific area measurements. Based on our results we propose different mechanisms for La1−xSrxMO3 (M = Mn, Fe, Ni, x = 0–0.3) obtaining, depending on the intermediary compounds formed in the combustion reaction or during the thermal treatment of the as-prepared powders.