Patent ID: 7141329

Claim:
An electrode having a microstructure of extended triple phase boundary with porous ion conductive ceria film coating wherein: an electrode for solid oxide fuel cells, sensors, or solid state devices, which is prefabricated to have independent electron and ion conductive paths, is coated with a porous oxygen ion conductive ceramic ceria film to provide a microstructure having an extended triple phase boundary where the electrode/electrolyte/gas are in contact; the electrode has a skeleton made of a material exhibiting electron conductivity or mixed conductivity; the coated film is made of a material exhibiting ion conductivity or mixed conductivity while continuously surrounding the electrode without any gap and without disconnecting the ion conductive path from a surface of the electrolyte; the coated film forms gas-permeable pores or fine pores therein or at an interface thereof with the electrode to provide the triple phase boundary; and wherein the porous oxygen ion conductive ceramic ceria film is made from one or more oxide sols selected from the group consisting of CeO 2 polymeric sol or particulate sol doped with up to 30% Gd, CeO 2 polymeric sol or particulate sol doped with Sm up to 30%, CeO 2 polymeric sol or particulate sol doped with Y up to 30%, CeO 2 polymeric sol or particulate sol doped with Sr up to 30%, CeO 2 polymeric sol or particulate sol doped with La up to 30%, and CeO 2 polymeric sol or particulate sol doped with Ca up to 30%.