Long-term durability of La0.75Sr0.25Cr0.5Mn0.5O delta-3 as a fuel electrode of solid oxide electrolysis cells for co-electrolysis

Abstract

Electrochemical conversion of carbon dioxide to a hydrocarbon fuel can reduce greenhouse emissions and lead to economic profits. Solid oxide electrolysis cells (SOECs) are potential candidates for decreasing CO2 emission due to their low electrical energy consumption properties for CO2 reduction. However, their fuel electrode, which is nickel-yttria stabilized zirconia (Ni-YSZ), shows critical durability issues. This study aimed to find an SOEC fuel electrode material among perovskite catalysts. The selected catalysts should satisfy the following properties: high catalytic performance in the reverse water gas shift (RWGS) reaction, low carbon deposition rate after the RWGS reaction, high electrical conductivity, and long-term durability in a co-electrolysis environment. Ni-YSZ and perovskite catalysts were fabricated. Their performance was investigated by considering the four properties. In this study, we found La0.75Sr0.25Cr0.5Mn0.5O delta-3 (LSCM) to be a promising SOEC fuel electrode. The LSCM electrode showed comparably good catalytic performance and electrical conductivity. A 1,200 h co-electrolysis test showed that the electrode had a stable performance.