Cobalt-free perovskite Pr0.5Sr0.5Fe1−xCuxO3−δ (PSFC) as a cathode material for intermediate temperature solid oxide fuel cells

•Cobalt-free Pr0.5Sr0.5Fe1−xCuxO3−δ (PSFC) cathodes successfully prepared by the citrate method.•PSFC cathodes are thermally compatible with CGO electrolytes.•Pr0.5Sr0.5Fe0.8Cu0.2O3−δ presents competitive area specific resistances of low activation energy, 0.62 eV.

PSFC (Pr0.5Sr0.5Fe1−xCuxO3−δ) is a new perovskite-type oxide that has gained considerable attention as cathode material for intermediate temperature solid oxide fuel cells (IT-SOFCs), due to its high mixed ionic-electronic conductivity below 800 °C. In this work, PSFC (Pr0.5Sr0.5Fe1−xCuxO3−δ, x = 0.2 and 0.4) powders were synthesized by the citrate method and structurally characterized by X-ray diffractometry. Screen-printed cathodes were sintered at 1050 °C and electrochemically characterized by impedance spectroscopy at 600–800 °C in pure oxygen. The area specific resistances (ASR) of the Pr0.5Sr0.5Fe0.8Cu0.2O3−δ material are shown to be competitive with typical values reported for cobalt-based cathodes in the measured temperature range, while, importantly, offering a significantly lower activation energy, 0.62 eV. The thermal expansion coefficients of these Co-free cathodes are in the range of 13–15 × 10−6 °C−1, in a temperature range 200–650 °C, demonstrating a good thermal compatibility with gadolinia doped ceria (CGO) electrolytes.

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