Electrochemical Performance and Stability of Manganese Doped La0.1Ca0.9TiO3 Anode of SOFC

Abstract

Manganese doped Lanthanum calcium titanate (La0.1Ca0.9Ti1-xMnxO3, LCTM, x= 0 – 0.8) perovskites were synthesized using a standard solid state reaction method. The crystallinity and microstructures were analyzed using X-ray diffraction and SEM. Furthermore, the electrical conductivity was measured under different PO2 atmosphere via a 4-probe method. LCTM was then screen printed onto a YSZ support, as the anode, to analyze the catalytic activity for both hydrogen oxidation and methane reforming reaction. On increasing manganese doping, the lattice parameter of the perovskite phase decreased due to smaller ionic radii of manganese compared to titanium. In addition, both electrical conductivity and power density were improved with increasing manganese doping up to a certain composition. Multi-oxidation states (likely to be oxidized) of manganese increased the concentration of oxygen vacancy and relative Ti4+ concentration compared to Ti3+, thus the electrochemical performance was improved. However, the electrical conductivity decreased with further increasing manganese doping due to decrease in the absolute concentration of titanium. In this work we study the effect of manganese doping on LCT, and analyzed the electrochemical and physical behavior of the material under anodic atmosphere.