Preparation and Electrochemical Performance of Ni Doped Ba0.5Sr0.5(Co0.8Fe0.2)1-xNixO3-δ Cathodes for Proton Ceramic Fuel Cells
The electrochemical performance of conventional mixed ionic-electronic conducting oxides Ba0.5Sr0.5Co0.8Fe0.2O3-δ (BSCF)in proton ceramic fuel cells(PCFCs)has been improved by using nickel doping strategy.A series of Ba0.5Sr0.5(Co0.8Fe0.2)1-xNixO3-δ samples were synthesized by using sol-gel method.Chemical compatibility and stability between the Ba0.5Sr0.5(Co0.8Fe0.2)0.9Ni0.1O3-δ(BSCFN10)cathode and the electrolyte BaZr0.1Ce0.7Y0.2O3-δ(BZCY)were studied,which was used in the PCFCs.Catalytic activity of the electrodes was evaluated by constructing a symmetric cell.It is showed that the BSCFN10 cathode has superior catalytic activity than BSCF.Peak power density of the BSCFN10 cathode was enhanced from 380 mW·cm-2 to 503 mW·cm-2 and the polarization impedance was reduced from 0.21 Ω·cm2 to 0.12 Ω·cm2,as compared with the undoped BSCF within a hydrogen atmosphere containing 3%water vapor at 700 ℃.In addition,the BSCFN10 electrode exhibited excellent operating stability at a current density of 0.4 A·cm-2,showcasing its potential for application in PCFCs.