Patent ID: 7820339

Claim:
A gas diffusion electrode that interfaces a liquid phase and a gaseous phase for electrochemical reduction of oxygen comprising: at least one reaction layer having dispersed therein a perovskite-type catalyst having alpha and beta sites, wherein the catalyst comprises a formula A 1−x A′ x (B 1−y B′ y ) z O 3+δ where x, y and z are mole fractions and z is greater than 1 and δ has a value in the range of about −0.30 to about 0.30, wherein A comprises a metal selected from the group consisting of La, Pr and Nd, A′ comprises one or more metals selected from the group consisting essentially of K, Rb, Cs, Ca, Sr, and Ba, B comprises a metal selected from the group consisting essentially of Mn, and Co, B′ comprises one or more metals selected from the group consisting essentially of Fe, and Ni, wherein said perovskite-type catalyst is catalytically active for the electrochemical reduction of oxygen at a current density greater than 0.2 A/cm 2 for a duration in an aqueous alkaline electrolyte greater than 200 hours; and at least one gas diffusion layer, wherein at least one reaction layer resides between an alkaline aqueous liquid and the gas diffusion layer and wherein at least one reaction layer is in fluid communication with the aqueous liquid and wherein the gas diffusion layer is in fluid communication with a gas comprising oxygen.