Efficient and controlled nano-catalyst solid-oxide fuel cell electrode infiltration with poly-norepinephrine surface modification

• Published in: Journal of power sources 2021-02, Vol.485 (C), p.229232, Article 229232
• Main Authors: Ozmen, O., Lee, S., Hackett, G., Abernathy, H., Zondlo, J.W., Sabolsky, E.M.
• Format: Article
• Language: English
• Subjects: Bio-surfactant; Infiltration; Nano-catalyst; SOFC
• ISSN: 0378-7753; 1873-2755
• DOI: 10.1016/j.jpowsour.2020.229232

There is a growing attention to enhance the performance of solid oxide fuel cell (SOFC) electrodes through the incorporation of nano-catalyst materials within the electrodes’ active sites. In this study, we report a technique for increased efficiency and microstructural control of the nano-catalyst infiltration process through polymerized norepinephrine (pNE) treatment. Nano-CeO2 catalysts were incorporated within both electrodes of commercial anode-supported SOFCs using a single salt solution step after a coating of pNE within the porous microstructure. The optimization of catalyst loading was performed by varying the cerium nitrate solution concentrations between 0.4 and 2.0 M. The ceria nanoparticles are distributed at the near-electrolyte region in both electrodes, but with microstructural variance due to the precursor molarity and solid loading. The time-dependent polarization resistance (Rp) variation was categorized into three zones by the nano-catalyst loading. Zone I referred to the baseline performance for the low-catalyst loading and fluctuating Rp. However, the cells in Zone II and III showed a continuous time-dependent activation as low as 0.275 Ω cm2 at 750 °C. The results suggest that the nano-CeO2 film reduces coarsening and related degradation of the backbone. In addition, the pNE-assisted dip infiltration enhanced infiltrant deposition efficiency by reducing the number of infiltration steps. •PNE, a catechol surfactant coating, enhances nano-catalyst deposition efficiency.•Cathode and anode electrodes were simultaneously infiltrated with nano-CeO2.•Nano-catalyst morphology was controlled by catalyst precursor concentration.•Nano-catalyst loading level was be used to tune electrode polarization.•Up to 33% lower Rp was achieved at 750 °C within 300 h operation.