Layered perovskites with exsolved Co-Fe nanoalloy as highly active and stable anodes for direct carbon solid oxide fuel cells

Abstract

The performance and stability of direct carbon solid oxide fuel cells (DCSOFCs) are severely affected by the electrocatalytic activity of their anode materials. In this work, a cobalt doped layered perovskite, (PrBa)0.95Fe1.8−xCoxNb0.2O5+δ (PBFCoxN, x = 0, 0.1, 0.2, 0.3), is investigated as the anode material for a DCSOFC. Co3Fe7 alloy particles are exsolved on the perovskite substrate under the reduction of carbon, which improves CO chemisorption and electrochemical oxidation. This enhances the electrochemical performance of the anode. The electrolyte-supported cell with a (PrBa)0.95Fe1.6Co0.2Nb0.2O5+δ (PBFCo0.2N) anode achieves a peak power density of 525.6 mW cm−2 at 800 °C, fueled by activated carbon. The performance of this anode material is comparable to or exceeds that of previously reported anodes, indicating that the PBFCo0.2N anode is a promising option for DCSOFCs.