Electrolyte forming process

A process of forming a structure including an electrolyte and an anode layer for a metal-supported solid-oxide fuel cell, the process comprising:

• a. providing a metal-supported anode layer comprising a metal substrate having an anode layer deposited thereon;
• b. combining a doped-ceria powder with a sintering aid and solvent to form a slurry;
• c. applying the slurry to the anode layer, wherein the slurry comprises doped-ceria powder with a bimodal particle size distribution;
• d. drying to form a green electrolyte;
• e. placing a mass on at least a part of the metal substrate to hold at least the part of the metal substrate flat during a step of firing the green electrolyte;
• and
• f. firing the green electrolyte in air at a sintering temperature that is less than 1100° C. to form a sintered electrolyte overlying the metal substrate and the anode layer thereon,
• wherein the metal substrate comprises a stainless steel foil substrate comprising a perforated region surrounded by a non-perforated region.