Electrochemical performance of La-doped Sr 2MgMoO 6− δ in natural gas

Abstract

Modification of the double perovskite Sr 2MgMoO 6− δ by La substitution has shown that Sr 2− x La x MgMoO 6− δ with 0.6 ⩽ x ⩽ 0.8 has better performance as the anode of a solid oxide fuel cell. With a Sr 1.2La 0.8MgMoO 6− δ anode, LSGM electrolyte, SrCo 0.8Fe 0.2O 3− δ cathode, and a La 0.5Ce 0.4O 1.7− δ buffer layer between the anode and the electrolyte, a maximum power density of 550 mW/cm 2 has been obtained for a SOFC operating on wet methane (3%H 2O) at 800 °C. The performance of the SOFC using C 2H 6 fuel, like that of CH 4, changes little on switching from dry C 2H 6 to 3% H 2O/C 2H 6, but improvement with wet C 3H 8 shows that some steam will need to be added to a moderately desulfurized natural-gas fuel.