Nickel-based bilayer thin-film anodes for low-temperature solid oxide fuel cells

Highlights: • Ni anodes with different nanostructures are fabricated for low-temperature SOFCs. • The Ni anodes are inferior to an optimized Pt anode in terms of catalytic activity. • A Ni/Ni-YSZ bilayer anode is introduced as an alternative to the Pt anode. • The bilayer anode successfully substitutes the Pt anode with 37% higher performance. • The full cell fabrication process is time-efficient and easy to scale-up. In this study, we investigate the possibility of using Ni-based anodes as alternatives to the Pt-based anodes for thin-film solid oxide fuel cells (SOFCs) operating at low temperatures. Anodes, electrolytes, and cathodes are sequentially sputtered onto a nanoporous substrate. The pure Ni anodes with modified nanostructures exhibit comparable performance as that of the optimized Pt anodes. Furthermore, a Ni/Ni-YSZ bilayer anode fabricated via a co-sputtering method exhibits approximately 37% higher peak power density than does the optimized Pt anode at 500 °C, demonstrating that noble metal anodes can be replaced by Ni-based anodes in low-temperature SOFCs by optimizing the anode nanostructure.