Novel gradient porous cathode for intermediate temperature solid oxide fuel cell

As a mixed ion electronic conducting oxide , PrBaCo 2 O 5+δ is regarded as a promising solid oxide fuel cell cathode. To further improve PrBaCo 2 O 5+δ cathode's oxygen reduction reaction activity, porosity graded PrBaCo 2 O 5+δ -based cathode is prepared by screen printing technology. With a porous top and a comparative denser base, oxygen ions concentration and oxygen gas concentration in the cathode can be graded distributed. This concentration gradient works as driven force which can enhance the cathode catalytic activity . And distribution of relaxation time analysis is carried out to investigate cathodes performance optimization mechanism, the result shows that gradient porous PrBaCo 2 O 5+δ cathode's area specific resistance value is much lower than the traditional homogeneous porosity PrBaCo 2 O 5+δ cathode. The scaffold porosity modification promotes the cathode oxygen ions transfer processes without obvious impact on the cathode oxygen surface processes.