Architecture-engineered low-Ni anodes based on dendritic GDC support and Ru nanofiber catalysts for durable SOFCs

Conventional nickel-based anodes in solid oxide fuel cells (SOFCs) face critical challenges, including carbon deposition, Ni particle agglomeration, and thermal expansion mismatch. In contrast, most nickel-free anode materials exhibit limited gas transport capabilities, severely constraining their electrochemical performance. To address these challenges, a bilayer anode architecture was developed, consisting of a dendritic porous GDC (Gd_0.1Ce_0.9O_2–δ) support and a thin Ni-GDC functional layer, aiming to achieve synergistic enhancement of gas diffusion and interfacial reaction activity through structural optimization. The GDC support was fabricated using a mesh-assisted phase inversion technique, resulting in a hierarchically interconnected pore network that improved gas transport pathways. By systematically adjusting the Ni doping content (6–18 wt%), the optimal composition was identified as 12 wt% Ni-GDC for the functional layer. At 750 °C, the dendritic-structured cell exhibited a 39.7% increase in maximum power density compared with conventionally pressed GDC supports. Subsequent incorporation of a Ru-GDC nanofiber catalyst layer further enhanced the cell performance by 28.9%. Long-term stability testing demonstrated that the bilayer anode structure maintained stable operation for 240 h, which was extended to 329 h upon incorporation of the catalyst layer. This bilayer design achieved excellent electrochemical performance and operational durability while significantly reducing nickel consumption, offering a promising strategy for the development of efficient, cost-effective, and environmentally friendly SOFC technologies.