Abstract: A new complexing agent Ethylene Diamine N,N0,N0,N0-Tetra N-Acetyl Diamine(EDTNAD), was used for Ba_0.5Sr_0.5Co_0:8Fe_0.2O_3-δ(BSCFO) synthesis. Some chemicals such as ammonia, nitric acid and citric acid were eliminated in comparison to the commonly used EDTA method. This agent makes complexing synthesis method a single step and causes more homogeneity in the liquid and solid phase. The sintering process was studied at temperatures between 1000 to 1200°C, heating-cooling rates of 1, 2, 5, 10°C/min and dwell time of 2, 5, 10 and 15 h. As-sintered membranes were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM), and density analysis. From the SEM images and X-ray diffraction of the BSCFO disks, it could be seen that above 1100°C, crystal intensity decreased, and melting and deformation of the disk occurred. The results show that in restricted temperature range, 1000-1100°C, 10% temperature increase leads to about a 4.5% density increase but a 200% increase in dwell time leads to about a 4% density increase. It could be concluded that the effect of temperature on grain growth, porosity and density is more than that of dwell time. Results also showed that the heating-cooling rate has no significant effect on grain size and density.

Key words: BSCFO, Membrane, Sintering, Grain size, Perovskite