Efficient CO2 electrolysis with scandium doped titanate cathode

Perovskite oxide (La,Sr)TiO3+δ (LSTO) cathode has demonstrated promising performance for direct CO2 electrolysis due to its unique redox-stable properties. However, insufficient electro-catalytic activity of titanate remains a major drawback that limits electrode performance. In this paper, catalytically active scandium is doped to LSTO to enhance cathode performances. The structure, electronic conductivity and ionic conductivity of La0.2Sr0.8Ti1−xScxO3+δ (LSTSxO) (x = 0, 0.05 and 0.1) are investigated and further correlated with electrode performances. XRD, TEM, TGA and XPS indicate the successful partial replacement of Ti by Sc in the B site of titanate. The improved electrode performances are strongly dependent on scandium doping contents. Promising direct CO2 electrolysis performance is demonstrated with near 100% current efficiency based on La0.2Sr0.8Ti0.9Sc0.1O3+δ at 1.7 V and 800 °C.