Partial oxidation of methane enabling complete coking resistance of Ni-YSZ anode supported solid oxide fuel cells

Abstract

• Partial oxidation of methane ensures complete coking resistance of Ni-YSZ. • Small decrease in cell performance can be observed with the oxygen content increasing. • Enhanced carbon activity is attributed to the partial oxidation of methane. • Incorporating partial oxidation and electrochemical oxidation is an effective approach. The utilization of natural gas as fuel for Ni-YSZ anode supported solid oxide fuel cells (SOFCs) is a most promising method to accelerate the commercialization process. However, the state-of-art Ni-based anode is sensitive to the natural gas, leading to the carbon formation and cell degradation. Herein, a catalytic partial oxidation approach is proposed by introducing different amounts of oxygen in methane for improving the coking resistance of Ni-based anode. The carbon activity is reduced from 400 to 0.4 when using 15%CH 4 -5%O 2 as fuel, and the electrochemical performance is only decreased by 10 %. Considering the working condition of SOFCs, a complete coking resistance of SOFC can be obtained by introducing only 1.25% O 2 at 0.59 V. This indicates that introducing a small amount of oxygen in methane is beneficial for improving coking resistance of SOFC under working condition.