Enhanced activities of CO2 electrolysis in solid oxide electrolysis cells via in-situ tailoring of La0.75Sr0.25Cr0.5Mn0.4Fe0.1O3-δ/Fe2P heterointerfaces

Abstract

Rational design of efficient and stable cathode materials is essential and important to directly and sustainably electrolyze CO2 into valuable chemical fuels of solid oxide electrolysis cell (SOEC). Herein, novel La0.75Sr0.25Cr0.5Mn0.4Fe0.1O3-δ/Fe2P heterointerfaces are in-situ tailored on the surface of La0.75Sr0.25Cr0.5Mn0.4Fe0.1O3-δ (LSCMF) cathodic skeleton for CO2 electrolysis. Benefitting from typical LSCMF/Fe2P heterointerfaces and additional oxygen vacancies, optimized CO2 adsorption, dissociation and electrolysis are obtained to boost electrolysis performances. As a proof, SOEC with the as-prepared r-LSCMF-P cathode delivers a current density of 866 mA cm−2 and a polarization resistance of 0.39 Ω cm2 at 800 °C and an applied voltage of 1.5 V, which demonstrates an over 2 times improvement of CO2 electrolysis performance compared to SOEC with the LSCMF cathode at the same condition. In addition, a lower attenuation rate of 0.43 mV h−1 could be observed for the SOEC after the direct CO2 electrolysis measurement up to 126 h. These results fully suggest that in-situ tailoring of LSCMF/Fe2P heterointerfaces is a feasible strategy to further improve activity of perovskite oxide for CO2 electrolysis.