Gas diffusion electrode for electrochemical oxygen reduction

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 a composition represented by the formula Nd1−xCax(Mn1−yFey)zO3+δ, wherein x has a value in the range of about 0.2 to about 0.5;
• y has a value in the range of about 0.0 to about 0.3;
• δ has a value in the range of about −0.3 to about 0.3, wherein said perovskite-type catalyst is catalytically active for the electrochemical reduction of oxygen at a current density greater than 0.2 A/cm2 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.

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 selected from La1−xRbx(Mn1−yFey)zO3+δ, where 0.15<x<0.25, 0<y<0.2, 1<z<1.02;
• La1−xCsx(Mn1−yFey)zO3+δ, where 0.1<x<0.3, 0<y<0.2, 1<z<1.02;
• Pr1−xSrx(Mn1−yFey)zO3+δ, where 0.3<x<0.5, 0<y<0.2, 1<z<1.02;
• Pr1−xCax(Mn1−yFey)zO3+δ, where 0.01<x<0.9, 0<y<0.9, 1<z<1.05;
• where δ has a value in the range of about −0.30 to about 0.30, wherein said perovskite-type catalyst is catalytically active for the electrochemical reduction of oxygen at a current density greater than 0.2 A/cm2 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.