Recent progress on design and fabrication of porous ceramics for solid oxide fuel cells

Abstract Solid oxide fuel cells (SOFCs) represent a promising technology for clean and efficient power generation. Porous ceramic electrodes are fundamental components to ensure the power generation of SOFCs by providing the gas flow channels and active sites for electrochemical reactions. Manipulation of the porous structure with electrodes is thus crucial for enhancing the electrochemical performance and operation stability, attracting considerable research efforts over the past decades. In this review, design criteria along with bioinspiration are summarized for the pore structure engineering of ceramic electrodes to facilitate mass transport and increase reaction sites of SOFC. Various fabrication techniques are introduced and compared for their advantages and disadvantages in creating porous electrodes with ideal hierarchical structures and performance. Specifically, as co‐sintering of different cell components is a critical step in the fabrication process of SOFCs, major obstacles and research progress of co‐sintering techniques of multilayer ceramics are summarized in detail. Basic mechanisms of the sintering process and the influence of typical processing variables are reviewed followed by a detailed discussion on the common strategies to address the complexity of the co‐sintering problem. Finally, this review provides a perspective on the remaining challenges of the design and fabrication of porous ceramics for more efficient SOFCs, particularly discussing the great potential of cell design learning from nature.