Fabrication of PrBa_0.5Sr_0.5Co_1.5Fe_0.5O_5+Δ Cathode By Inkjet Printing for High Performance Protonic Ceramic Fuel Cells

Proton ceramic fuel cells (PCFC) have recently received great attention due to their high output and long-term stability along with hydrogen as well as hydrocarbon fuel in the intermediate temperature region (400-600 ºC) where solid oxide fuel cells do not work properly. The development of a new perovskite cathode such as BaCo0.4Fe0.4Zr0.1Y0.1O3-δ (BCFZY) and PrBa0.5Sr0.5Co1.5Fe0.5O5+δ (PBSCF) was key to the success of high performance PCFCs. Of these materials, PBSCF is considered promising with relatively high two-phase (electron/hole-ion) conductivity and long-term stability. Therefore, the development of a manufacturing method for producing a high quality PBSCF layer is of great interest in the field of ceramic fuel cells. In this study, we have succeeded in fabricating porous PBSCF layers using the inkjet printing method. PBSCF slurry inks for printing have been successfully synthesized in ethanol solutions, satisfying the rheological properties required for inkjet printing. The thickness and pore size of the layers were controlled by the number of prints and color levels of the print image, respectively. To verify the feasibility of this technology, a commercial HP printer was used in manufacturing. As a result, we have confirmed a high output over 0.8 W/cm2 at 600 ºC from our PCFCs with about 10μm-thick BaZr0.2Ce0.6Y0.1Yb0.1O3 (BZCYYb2611) electrolyte. This performance is close to the highest PCFC performance ever reported. In addition, we have confirmed that it maintains its performance even in long-term stability tests of more than 100 hours. Our findings are expected to contribute to the easy and economical production of high performance PCFC components.