Solid oxide steam electrolysis cell, a promising electrical-chemical conversion device for the next generation efficient hydrogen production and energy storage, has been actively studied because of their high energy conversion efficiencies and prospective applications as electrochemical reactors. After decades of research on protonic ceramic materials, remarkable advances have been made in the protonic ceramic electrochemical cells (PCECs) air electrode and electrolyte. However, the existing air electrodes are far from satisfying the requirements of practical applications, a series of issues, including the lack of active and durable electrodes, greatly limit the commercialization. To date, the systematic development of triple conducting catalysts remains abstruse because of the challenges of characterizing protonic behavior. A quantitative properties assessment and prediction on protonic properties of perovskite are still not available.

Starting with a computational fluid dynamic modeling on the protonic ceramic electrochemical cells (PCECs) air electrode, we focused on the materials design of air electrode materials by employing model guidance, operating durability optimization by electrode structure engineering, as well as the air electrode surface tailoring to overcome the most rate-limiting step. Thus, the electrochemical performance and durability of PCEC care comprehensively improved. The fabrication methods, characterization techniques with electrochemical performance are presented. Further work plans and implications are proposed regarding optimizing the structure of materials, preparation technology, and better understanding the role of these triple conductors. This research is expected to provide an in-depth understanding and offer avenues in the rational design of PCEC with long operational life and high energy/power density in the near future.