Fluorinated Air Electrodes for Enhanced Re-PCEC Performance through Ultrafast Sintering Method

Reversible protonic ceramic electrochemical cells (Re-PCECs) have been widely recognized as a promising energy conversion technology due to their ability to generate electricity efficiently or produce chemicals on demand. Their advantages over conventional reversible solid oxide cells reside in lower operating temperatures (400–700 °C) and undiluted fuel stream, resulting in lower manufacturing and operating costs. In the low-temperature range, the performance of Re-PCECs primarily depends on the air electrode. F substitution can enhance the bifunctional electrocatalytic activity of Re-PCEC air electrodes by improving their hydration capability and, thus, their protonic conductivity. However, due to the high volatility of F, incorporating this element into Re-PCEC air electrode materials through conventional methods is difficult. This study overcomes this limitation through in situ ultrafast high-temperature sintering (UHS) as a method of producing fluorinated Re-PCEC air electrodes. Comparative analysis of triple conducting oxide electrodes Ba0.9Fe0.9Zr0.1O3-δ and Ba0.9Fe0.9Zr0.1O2.9-δF0.1, prepared through both conventional and UHS methods, reveals that in situ UHS-sintered materials exhibit enhanced catalytic performance and durability. Furthermore, in situ UHS technology enables the controlled incorporation of F, offering an effective method for preparing high-performance fluorinated ceramic catalysts.