Effects of manganese substitution at the B-site of lanthanum-rich strontium titanate anodes on fuel cell performance and catalytic activity

Abstract Sr 0.4 La 0.6 Ti 1− x Mn x O 3− δ with rhombohedral structure has been investigated in terms of their electrochemical performance, redox stability, and electro-catalytic properties for solid oxide fuel cell anodes. The performance of Sr 0.4 La 0.6 Ti 1− x Mn x O 3− δ anodes for solid oxide fuel cells strongly depends on the Mn substitution at the B-site of the perovskites. Electrical conductivity of Sr 0.4 La 0.6 Ti 1− x Mn x O 3− δ increases with increasing Mn content. X-ray photoelectron spectroscopy analysis reveals that the amount of Mn 3+ and Ti 3+ , which is an electronic charge carrier, increases with Mn doping. The reduced anode powders with high Mn/Ti ratio show oxygen storage capability and a low carbon deposition rate. Linear thermal expansion coefficients of Sr 0.4 La 0.6 Ti 1− x Mn x O 3− δ anodes range from 9.46×10 −6 K −1 to 11.3×10 −6 K −1 . The maximum power densities of the single cell with the Sr 0.4 La 0.6 Ti 0.2 Mn 0.8 O 3− δ anode in humidified H 2 and CH 4 at 800 °C are 0.29 W cm −2 and 0.24 W cm −2 , respectively.