Enhancement of oxygen separation performance through Pr_0.6Sr_0.4FeO_3- perovskite by modulation of oxygen vacancies

Perovskite-type oxides are promising for oxygen separation purification as oxygen uptake materials. However, their separation performance is limited by the low concentration of oxygen vacancies. Hence, in this work, the low valence Cu is doped to introduce more oxygen vacancies, and a series of Pr0.6Sr0.4Fe1-xCuxO3-delta (x = 0, 0.05, 0.1, 0.15) oxides have been developed to investigate the effects of the Cu contents on the oxygen separation performance. The introduction of Cu in Pr0.6Sr0.4FeO3-delta effectively regulates the concentration of oxygen vacancies and significantly reduces the average metal-oxygen bond energy, thus promoting oxygen separation performance. Especially, Pr0.6Sr0.4Fe0.9Cu0.1O3-delta exhibited the enhanced oxygen adsorption capability (0.195 mmolg(-1)) and average desorption rate (7.8 mu molg(-1)min(-1)) at 600 degrees C, which are 1.35 and 1.78 times of the parent Pr0.6Sr0.4FeO3-delta respectively. This work provides a successful strategy for optimizing the oxygen separation performance of perovskite materials.