Preparation and characteristics of Ba 0.5Sr 0.5Co 0.8Fe 0.2O 3− δ cathodes for IT-SOFCs by electrostatic slurry spray deposition

Abstract

To solve the interfacial peeling-off problem of cathode materials Ba 0.5Sr 0.5Co 0.8Fe 0.2O 3− δ (BSCF), electrostatic slurry spray deposition (ESSD) was applied. The BSCF cathode was deposited on a CGO pellet by ESSD and the electrochemical performance of the BSCF cathode is investigated at various temperatures (650–800 °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 Ω cm 2 at 650 °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.