NdBaFe2-xCoxO5+δ Double Perovskites with Exsolved Co-Fe Alloy Nanoparticles as Highly Efficient and Stable Anodes for Direct Hydrocarbon Solid Oxide Fuel Cells

Exsolution of transition metals in perovskites is a potential way to improve the catalytic activity of fuel cell anode materials. In this work, the double-perovskite anodes PR-NdBaFe2-xCoxO5+delta (x = 0.1, 0.2; PR-NBFC10, PR-NBFC20) with the exsolved Co0.72Fe0.28 metal alloy nanoparticles were obtained by heat treatment in 5% H-2/Ar post-reduction at 850 degrees C. The exsolved Co-Fe alloy nanoparticle catalyst uniformly distributed on the surface of the cobalt-doped PR-NBFC10 and PR-NBFC20 ceramic anodes facilitates the catalytic activity compared with the undoped PR-NdBaFe2-xCoxO5+delta (x = 0; PR-NBFCO) anode. The maximum power density of single cells with PR-NBFCO, PR-NBFC10, and PR-NBFC20 anodes supported by a 200 mu m thick La0.9Sr0.1Ga0.8Mg0.2O3-delta electrolyte at 850 degrees C in wet H-2 reached 842, 1110, and 1247 mW cm(-2), respectively. In addition, PR-NBFC0, PR-NBFC10, and PR-NBFC20 exhibit relatively stable output power in a wet CH4 fuel within 100 h of operation. Since the exsolved Co-Fe alloy nanoparticles have an embedded structure, they exhibit impressive anticoking properties, which greatly expand their application. The PR-NBFC double perovskite containing Co-Fe alloy nanoparticles offers possibilities for finding promising high-catalytic-activity and high-stability anodes for solid oxide fuel cells.

Automated summary

Exsolution of Co-Fe alloy nanoparticles in double perovskite anodes has been shown to significantly enhance catalytic activity and stability in solid oxide fuel cells under both wet H-2 and wet CH4 conditions. This study demonstrates the potential of using exsolved transition metals to improve fuel cell performance.