High-performance Ni/Pt Composite Catalytic Anode with Ultra-Low Pt Loading for Low-temperature Solid Oxide Fuel Cells

Abstract

In this study, we developed a Ni/Pt bilayer catalytic anode that has high electrochemical activity and significantly reduced Pt loading amount, for low-temperature solid oxide fuel cells (LT-SOFCs). The Ni/Pt bilayer anodes with various thicknesses of the Pt catalytic active layer were fabricated on yttria-stabilized zirconia substrates via the direct current sputtering technique, and their performances were evaluated for the LT-SOFCs. The optimal thickness of the Pt catalytic layer for the Ni/Pt bilayer was found to be 10 nm based on the results for the fuel cell performance and electrochemical impedance spectroscopy (EIS) analysis. The optimal Pt10/Ni140 anode showed a cell performance and polarization resistance very similar to those of a reference single-phase Pt anode, while having only 7% of the Pt loading amount of the reference Pt anode. For the detailed morphological analysis of the bilayer structure anode, we employed the pull-off delamination process to analyze both the surface and interface morphologies of the bilayer anodes and the interface morphology of the Ni/Pt bilayer anodes after the operating test was analyzed. The results presented herein indicate the suitability of the methodology for the morphological analysis of thin-film bilayer structures and contribute to reduce the cost of membrane electrode assembly fabrication for LT-SOFCs, thus facilitating the commercialization of these systems.