NiCu–Zr0.1Ce0.9O2−δ anode materials for intermediate temperature solid oxide fuel cells using hydrocarbon fuels

NiCu–Zr0.1Ce0.9O2−δ based cermets are evaluated as anode materials for intermediate temperature solid oxide fuel cells (IT-SOFCs) using hydrocarbon fuels. Polarization curves and stability tests are conducted for direct methane SOFCs with various anode materials at 700 °C. The performances and thermal stabilities of the cells with Zr0.1Ce0.9O2−δ based anodes are significantly higher than those using pure CeO2-based anodes, indicating by doping 10 mol% Zr into CeO2, the thermal stability and anode performance can be improved. Among the anode materials investigated, the best performing anode is Ni–Zr0.1Ce0.9O2−δ. The cell using the Ni0.5Cu0.5–Zr0.1Ce0.9O2−δ anode exhibits a similar performance to that with the Ni–Zr0.1Ce0.9O2−δ anode, but experiences a much lower degradation after a short-term operation in weakly humidified CH4. The cell using the Cu–Zr0.1Ce0.9O2−δ anode shows the best stability, only 0.61% degradation after a 48 h operation, but a low performance as well. The results suggest that NiCu–Zr0.1Ce0.9O2−δ based cermets could be promising candidate anodes for direct hydrocarbon IT-SOFCs.

► By doping Zr into ceria, thermal stabilities and activities of anodes are improved. ► The best performing anode is Ni–Zr0.1Ce0.9O2−δ cermet. ► The best thermally stable anode is Cu–Zr0.1Ce0.9O2−δ cermet. ► Ni0.5Cu0.5–Zr0.1Ce0.9O2−δ anode achieves both high stability and high activity. ► Ni–Cu alloy–Zr doped CeO2 can be promising candidate anode materials.