Effects of Ceria Addition on Ni/YSZ Anodes for SOFC’s Operating With Syngas and n-Butane Available to Purchase

This study explores the incorporation of ceria (CeO₂) into Ni/YSZ cermet anodes for solid oxide fuel cell performance with both syngas and n-butane/steam feeds to suppress carbon deposits and expand operability of Ni-based anodes with carbonaceous fuel feeds. CeO₂ was co-fired with Ni/YSZ cermets to form a porous anode support layer (1 mm thick), which was tested in SOFC button cells with dense YSZ electrolytes (10–20 μm thick) and porous LSM/YSZ cathodes (∼50 μm thick). The co-fired Ni/CeO₂/YSZ anode-supported cells were tested from 700 to 800 °C on various fuels including syngas and n-butane with H₂O added at a 1.5-to-1 and a 1-to-1 steam-to-carbon (S/C) ratio. Electrochemical characterization revealed that CeO₂ addition provided stable performance with high power densities at 800 °C — up to 0.6 W/cm² on syngas and 0.35 W/cm² on direct butane feeds — without significant carbon deposition as observed for Ni/YSZ anodes without CeO₂. Testing with syngas at different H₂ and CO partial pressures indicated that high power densities can be maintained along an anode channel for up to 50% fuel conversion. The results indicate that CeO₂ addition to Ni/YSZ may provide a viable means for stable SOFC operation on either pre-reformed or direct light-hydrocarbon fuel feeds.