Electrochemical performance of double perovskite Pr2NiMnO6 as a potential IT-SOFC cathode
Résumé
Double perovskite oxide Pr2NiMnO6 is evaluated as a potential cathode for intermediate-temperature solid oxide fuel cells (IT-SOFCs). The reactivity test indicates that no reaction occurs between Pr2NiMnO6 and CGO at 1200 °C in air. The thermal expansion coefficients (TEC) of Pr2NiMnO6 are 10.6 × 10−6 K−1 in air and 11.5 × 10−6 K−1 in nitrogen atmosphere within a temperature range of 100–800 °C. The electrochemical properties of Pr2NiMnO6 cathode are characterized by ac impedance and dc polarization methods, respectively. The lowest area specific resistance (ARS) is 0.38 Ω cm2 at 700 °C in air. The dependence of ASR with oxygen partial pressure indicates that the charge transfer process is the rate-limiting step for oxygen reduction reaction on Pr2NiMnO6 cathode.