Membrane electrode assembly and solid oxide fuel cell

A solid oxide fuel cell comprising a membrane electrode assembly including:

• an electrode consisting of at least one compound selected from the group consisting of lanthanum strontium cobalt complex oxide, lanthanum strontium cobalt ferrite complex oxide, lanthanum strontium ferrite complex oxide, and lanthanum nickel ferrite complex oxide or consisting of a composite of the compound and an electrolyte material;
• a first solid electrolyte membrane represented by a composition formula of BaZr1-xlnxO3−δ (0<x<1);
• and
• a second solid electrolyte membrane having a composition different from the composition of the first solid electrolyte membrane,
• wherein the first solid electrolyte membrane has a first surface in contact with the electrode and a second surface, which is a surface opposite to the first surface, in contact with the second solid electrolyte membrane, and
• wherein the electrode, the first solid electrolyte membrane, and the second solid electrolyte membrane are stacked in this order.