Ca-Doped Double Perovskite PrBa0.8Ca0.2Co2O5+δ Thin-Film Electrodes: Experimental and Theoretical Study

Geometrically well-defined thin-film electrodes of Ca-doped double perovskite, PrBa0.8Ca0.2CoO5+delta (PBCaCO), were fabricated using a spray pyrolysis system. The area specific resistance (ASR) of the electrode was calculated to be 7.1 Omega. cm(2) at 973 K in air, which was observed to decrease on increasing temperature. The corresponding diffusivity of oxygen anion was calculated using molecular dynamics (MD) simulations and compared to un-doped PrBaCo2O5+delta (PBCO). At 973 K, Ca-doping did not show any improvement in the diffusivity of the PBCaCO structure, since diffusivity for the doped PBCaCO (D = 1.83 x 10(-8) cm(2). s(-1)) was comparable to the un-doped PBCO (D = 1.00 x 10(-8) cm(2). s(-1)). The improved electrochemical performance of the Ca-doped electrode was thus attributed to reduced surface segregation and henceforth better surface electrocatalytic activity.