Novel Approach for Developing Dual-Phase Ceramic Membranes for Oxygen Separation through Beneficial Phase Reaction

详细信息    查看全文

• 作者：Zhenbao Zhang ; Wei Zhou ; Yubo Chen ; Dengjie Chen ; Jiawei Chen ; Shaomin Liu ; Wanqin Jin ; Zongping Shao
• 刊名：ACS Applied Materials & Interfaces
• 出版年：2015
• 出版时间：October 21, 2015
• 年：2015
• 卷：7
• 期：41
• 页码：22918-22926
• 全文大小：485K
• ISSN：1944-8252

文摘

A novel method based on beneficial phase reaction for developing composite membranes with high oxygen permeation flux and favorable stability was proposed in this work. Various Ce_0.8Sm_0.2O_{2鈭捨?/sub> (SDC) + SrCO3+Co3O4 powders with different SDC contents were successfully fabricated into membranes through high temperature phase reaction. The X-ray diffraction (XRD) measurements suggest that the solid-state reaction between the SDC, SrCO3 and Co3O4 oxides occurred at the temperature for membrane sintering, leading to the formation of a highly conductive tetragonal perovskite phase SmxSr1鈥?i>xCoO3-未. The morphology and elemental distribution of the dual-phase membranes were characterized using back scattered scanning electron microscopy and energy dispersive X-ray spectroscopy (BSEM-EDX). The oxygen bulk diffusivity and surface exchange properties of the materials were investigated via the electrical conductivity relaxation technique, which supported the formation of conductive phases. The SDC+20 wt % SrCO3+10.89 wt % Co3O4 membrane exhibited the highest permeation flux among the others, reaching 0.93 mL cm^鈥? min^鈥? [STP = standard temperature and pressure] under an air/helium gradient at 900 掳C for a membrane with a thickness of 0.5 mm. In addition, the oxygen permeation flux remained stable during the long-time test. The results demonstrate the beneficial phase reaction as a practical method for the development of high-performance dual-phase ceramic membranes.}