Recent Progress and Challenges in Mixed Ionic–Electronic Conducting Membranes for Oxygen Separation

Abstract

Carbon neutrality refers to the state of making net‐zero emissions of carbon dioxide (CO2), which is a key concept in tackling global warming. It can be achieved by offsetting carbon emissions as well as balancing reduced and emitted emissions. Globally, CO2 is emitted mainly from fossil fuel power plants. The use of carbon capture and storage technology, including pre‐, post‐, and oxy‐fuel combustion capture, in power plants can provide a carbon‐neutral strategy that allows for the sustainable use of fossil fuels while potentially reducing CO2 emissions. Oxy‐fuel combustion capture facilitates CO2 capture by simplifying combustion products through the reaction of recirculated flue gas with a high‐purity oxygen. Oxygen transport membranes, which produce pure oxygen by oxygen transport via oxides at high temperatures, have attracted increased interest because they can improve overall efficiency when integrated with oxy‐fuel combustion capture. Dual‐phase membranes with fluorite structure have greater potential for commercialization than perovskite‐based single‐phase membranes, which have poor chemical and mechanical properties. However, despite these advantages, their low oxygen permeability remains a critical issue. This review focuses on progress in the development of dual‐phase membranes and summarizes various approaches that can facilitate bulk diffusion and surface exchange, which affect the oxygen permeability.

Advancements in Perovskite‐Based Cathode Materials for Solid Oxide Fuel Cells: A Comprehensive Review

“…It is commonly accepted that maintaining a higher ratio of fluorite phase than perovskite phase in dual membranes will yield a membrane with increased stability. [92] Therefore, doped ceria is commonly employed as infiltrating promoters over cobaltite-based cathode scaffolds for SOFC. [93] For instance, Joo et al [94] conducted a study to investigate oxygen flow in a fluorite-rich dual-phase membrane, composed of 80 vol % Ce 0.9 Gd 0.1 O 2-δ and 20 vol% La 0.6 Sr 0.4 Co 0.2 Fe 0.8 O 3δ ).…”

Multiplying Oxygen Permeability of a Ruddlesden‐Popper Oxide by Orientation Control via Magnets

“…However, it is essential to consider that the coating materials often contain elements such as Sr and Co (e.g. La 0.6 Sr 0.4 CoO 3− δ ), which destabilize in CO 2 or even in air after long‐term storage and adversely impede the oxygen flux [8b,9c,10] …”

Perspectives on achievements and challenges of oxygen transport dual‐functional membrane reactors

“…There have been numerous reviews that provide in-depth summaries of the applications of these two types of OTM reactors. 1,[4][5][6][7][8] In recent years, there has been growing interest in coupling two distinct reactions through an OTM reactor to speed up chemical reactions due to advancements in the stability of membrane materials. [8][9][10][11] The coupling reaction can be accomplished by decomposing oxygen-containing gases (e.g., H 2 O and CO 2 ) in combination with another oxidative process for improving the oxygen extraction efficiency such as POM.…”

“…These reactions include CO 2 decomposition, nitric oxide decomposition, and water splitting (WS). There have been numerous reviews that provide in‐depth summaries of the applications of these two types of OTM reactors 1,4–8 . In recent years, there has been growing interest in coupling two distinct reactions through an OTM reactor to speed up chemical reactions due to advancements in the stability of membrane materials 8–11 .…”