The principles for rationally designing H-SOFC anode active layer

Abstract

To ascertain the function and principles of anode active layer (AAL) for proton-conducting solid oxide fuel cells (H-SOFCs), a thorough inquiry of the optimum Ni cermet in typical NiO-BaZr0.1Ce0.7Y0.2O3-δ (NBZCY) AAL is managed. Both the power and polarization enhance with increasing NiO from 40 to 65 wt.% (NBZCY65-35), possessing the optimal performance with the polarization resistance of 0.039 Ω cm2 and power output of 983 mW cm−2 at 700 °C. This derives from the sufficient porosity and maximum triple phase boundaries for 1:1 vol of Ni and BaZr0.1Ce0.7Y0.2O3-δ after anode reduction. In contrast, the remarkably performance degradation for NBZCY70-30 AAL could be attributed to the inadequate proton transmission. In short, the deficient metal catalyst in NBZCY (NiO ≤ 60 wt.%) could not provide enough electrocatalysis, while the insufficient BaZr0.1Ce0.7Y0.2O3-δ in NBZCY70-30 limits the proton transfer. The principles could give a guidance for designing high active electrodes in electrocatalytic fields.