Activity and deactivation of La0.8Ca0.2Cr0.9X0.1O3 (X = Ni, Co) in dry methane using temperature-programmed techniques Original Research Article

A combination of temperature-programmed (TP) and isothermal experiments were performed on the candidate solid oxide fuel cell (SOFC) anode materials, La0.8Ca0.2Cr0.9X0.1O3 (X = Ni, Co), to investigate their suitability for use with dry methane feeds. Comparing with the behaviour of the unsubstituted material, La0.8Ca0.2CrO3 [1], the Ni and Co doping were found to have a marked modifying effect on the ease and extent of reduction of the materials. The total extent of reduction was higher than for the unsubstituted oxide. Two main reaction regimes were identified, as for the unsubstituted material, involving complete oxidation and methane dissociation. Complete oxidation only occurred over the pre-oxidised material. When reduced at high temperatures, the Ni-substituted material displayed behaviour characteristic of both La0.8Ca0.2CrO3 and Ni-YSZ cermet [2] indicating that segregation of Ni occurs during high temperature reduction.