Sr(Ti0·3Fe0.7)O3−δ-based perovskite with in-situ exsolved Fe–Ru nanoparticles: A highly stable fuel electrode material for solid oxide electrochemical cells with efficient electrocatalytic CO2 reduction ability and preferential selectivity

Abstract

The development of solid-oxide cells requires fuel electrodes capable of promoting highly catalytic activities for CO2 electrochemical reduction (CO2R). This study develops a fuel electrode material, Sr(Ti0·3Fe0·63Ru0.07)O3-δ (STFR) perovskite, enhance with in-situ exsolved Fe–Ru nanoparticles (STFR–FeRu), demonstrating excellent electrochemical catalytic activity for CO2R, considerable stability, and high selectivity for CO2 electrolysis. Notably, the study discovered for the first time that STFR–FeRu exhibits significantly enhanced catalytic activity in a CO2-containing atmosphere compares to that in hydrogen-based fuels. At 800 °C and 1.3 V, La0·8Sr0.2Ga0.8Mg0·2O3-δ electrolyte-supported cells with STFR–FeRu fuel electrode, for direct CO2 electrolysis, realizes a current density of 1.77 A cm−2. This current density is 50 % higher than that of H2O electrolysis under the same conditions. Additionally, the cell achieves a current density of 1.54 A cm−2 for CO2–H2O co-electrolysis, with a high CO2 electrolysis selectivity (CO concentration exceeding 60 % in the electrolysis products).