Preparation and characteristics of Ba0.5Sr0.5Co0.8Fe0.2O3-delta cathodes for IT-SOFCs by electrostatic slurry spray deposition

Abstract

To solve the interfacial peeling-off problem of cathode materials Ba0.5Sr0.5Co0.8Fe0.2O3-delta (BSCF), electrostatic slurry spray deposition (ESSD) was applied. The BSCF cathode was deposited on a COO pellet by ESSD and the electrochemical performance of the BSCF cathode is investigated at various temperatures (650-800 degrees C) and oxygen partial pressures (0.15-0.8 atm). Microstructural observation showed that the BSCF/CGO half cell exhibited good adhesion between cathode and electrolyte layers without any cracks for peeling-off problem. The polarization resistance was estimated to 1.78 Omega cm(2) at 650 degrees C and the average activation energy was 118.8 kJ mol(-1). The dependence of polarization resistances on Po-2 shows that the rate-determining step of the oxygen reduction reaction in the prepared BSCF cathode is the charge transfer between electrolyte and electrode.