Investigation of Co–doped Ce0.8Sm0.2O2–δ–Ba0.95La0.05Zr0.1Fe0.9–xCoxO3–δ Dual–phase Oxygen Transport Membranes

Abstract

In this study, 60 wt% Ce0.8Sm0.2O2–δ–Ba0.95La0.05Zr0.1Fe0.9–xCoxO3–δ (SDC–BLZFC, x = 0–0.4) dual–phase oxygen transport membranes were prepared by a combined EDTA–citrate complexing sol–gol method. The effects of partial substitution of iron by cobalt on the crystal structure, phase structural stability, oxygen permeation flux and CO2–tolerance were systematically investigated by XRD, TG and oxygen permeation experiment. The sample with x = 0.4 had the highest oxygen permeation flux of 0.42 ml min-1 cm-2 in He, while decreased most sharply after switching into pure CO2. The result of sample with x = 0 was opposite. From all results, it could indicate that Co–doping contributes to oxygen permeation flux in inert gases and phase structural stability, but would reduce the CO2–tolerance of SDC–BLZFC dual–phase membranes.