Composite Oxygen Electrode Based on LSCM for Steam Electrolysis in a Proton Conducting Solid Oxide Electrolyzer

This paper presents a ceramic composite oxygen electrode (La 0.75 Sr 0.25 ) 0.95 Mn 0.5 Cr 0.5 O 3-δ (LSCM) – BaCe 0.5 Zr 0.3 Y 0.16 Zn 0.04 O 3-δ (BCZYZ) for steam electrolysis in a proton-conducting Solid Oxide Electrolyzer (SOE) with proton conducting electrolyte BCZYZ and fuel electrode BCZYZ/Ni at 700°C. AC impedance spectroscopy and I-V tests demonstrate two main processes from 0 to 2 V with 3%H 2 O/N 2 vs 5% H 2 /Ar: reoxidation of the LSCM electrode below 1.2 V and oxidation of H 2 O above 1.2 V. The current density reaches 2 Acm −2 at 2 V with electrode polarization of 0.1 Ωcm 2 and steam electrolysis shows short term stability with current efficiency of 22%.