Enhancement of anode activity at Ni/Sm-doped CeO2 cermet anodes by Mo addition in NH3-fueled solid oxide fuel cells

Molybdenum was added to nickel/Sm2O3-doped ceria (Ni/SDC) cermets by a MoCl5 impregnation method, and the activity of the resulting Ni-Mo/SDC cermets was evaluated as anodes in ammonia-fueled solid oxide fuel cells (SOFCs) in the temperature range of 973-1173 K. It has been revealed that the addition of Mo improved remarkably the catalytic activity for NH3 reforming and enhanced the cell performance. The Ni-Mo/SDC anode with a Mo content of ~ 3 atomic % of the total metal showed the highest catalytic activity for NH3 reforming. XRD analysis of a NiO-MoO3 powder mixture annealed in NH3 revealed the formation of a nitride NixMo1-xN during operation of Ni-Mo/SDC anodes, and the role of the nitride in NH3 reforming was discussed in detail.