Achieving excellent CO2/H2O conversion performance in symmetrical solid oxide electrolysis cells through in situ exsved Ni–Fe alloy nanoparticles

Abstract

Symmetric solid oxide electrolysis cells (SSOECs) are widely studied because they can simplify the preparation process and save costs. In this study, high-performance symmetric electrode material La0.5Sr0.5Fe0.8Ni0.1Nb0.1O3-δ (LSFNiNb) is proposed. A heterogeneous structure with high catalytic activity is constructed via in-situ exsolution of Ni–Fe alloy nanoparticles (NPs). LSFNiNb shows the highest electrical conductivity of 157 S cm−1 in the air at 650 °C. In an atmosphere of 5% H2–95% N2, the polarization impedance is 0.302 Ω cm2 at 800 °C. While the current density is 0.767 A cm−2 in 60% CO2–20% H2O-20% H2, at 800 °C and 1.5 V. In addition, there is no significant degradation in SOEC mode at a current density of 0.2 A cm−2 for 110 h.