High performance and stability of double perovskite-type oxide NdBa0.5Ca0.5Co1.5Fe0.5O5+δ as an oxygen electrode for reversible solid oxide electrochemical cell

Abstract In this study, we successfully synthesized double perovskite-type oxide NdBa0.5Ca0.5Co1.5Fe0.5O5+δ (NBCCF) using a conventional wet chemical method as the oxygen electrode for reversible solid oxide electrochemical cells (RSOCs). The polarization resistance (Rp) of the composite electrode NBCCF-Gd0.1Ce0.9O2 (GDC) is only 0.079 Ω cm2 at 800°C under air. The single cell based on NBCCF-GDC electrode displays a peak power density of 0.941 W/cm2 in fuel cell mode and a low Rp value of 0.134 Ω cm2. In electrolysis cell mode, the cell displays an outstanding oxygen evolution reaction (OER) activity and shows current density as high as 0.92 A/cm2 with 50 vol% AH (Absolute Humidity) at 800°C and applied voltage of 1.3 V. Most importantly, the cell exhibits admirable durability of 60 h both in electrolysis mode and fuel cell mode with distinguished reversibility. All these results suggest that NBCCF is a promising candidate electrode for RSOC.