Sr-substitution Effects on La-NiO3, Sol-Gel Synthesis, Structural and Electrical Properties

IN ORDER to investigate Sr-substitution effects on LaNiO3, LSN, properties, thermal analysis, x-ray diffraction, and scanning electron microscopy studies were used to characterize powder samples of La1-xSrxNiO3, x= 0, 0.3, 0.5, 0.8 and 1, prepared by the sol-gel route via the polymerized complex method. Electrical conductivity and dielectric properties of the different compositions were also done. Samples of the complex solutions of molar ratios La (Sr)/Ni/citric acid (CA)/ethylene glycol (EG) = 1: 1: 10: 40, were heated at 130 degrees C to reach a gel form, dried at 350 degrees C, crushed to the precursor powder LSN, then final calcination was performed at 800 degrees C/2hr in air according to thermal analysis results. Elemental analysis through the EDS spectroscopy confirms the compositions. Ultrafine, nanoparticle samples having perovskite (ABO3) tetragonal crystalline were formed except that of x= 1, SrNiO3, which has a cubic one. The conduction mechanism changes from semi-conductive to metallic as Sr-incorporation increases and, sigma seems to be temperature independent, while the dielectric values increase.