La-doped Ba0.5Sr0.5Co0.8Fe0.2O3- d as Cathode for Protonic-Conducting Solid Oxide Fuel Cells with Enhanced Structure Stability

As a highly efficient energy conversion device, proton-conducting solid oxide fuel cells (SOFCs) have attracted intensive attention due to its high performance at intermediate temperature.1 Ba0.5Sr0.5Co0.8Fe0.2O3-d (BSCF), as an excellent air electrode material for oxygen-ion conducting SOFCs,2 nevertheless, is not effective when employed in SOFCs. There are several factors limiting the of BSCF, including 1) large amount Ba2+ A-site makes unstable atmosphere containing steam and carbon dioxide acid gases which might occupy active sites oxygen reduction on surface cathode; 2) The ionic radius distance between B-site metal far away, suppressing electron conduction resulting low conductivity BSCF.3