Microstructure and Polarization characteristics of LSCF-GDC Composite Cathode with Different Volume Fractions

Abstract

In the present study, La0.6Sr0.4Co0.2Fe0.8O3 (LSCF)-Gd0.1Ce0.9O1.95 (GDC) composite cathodes with different volume fractions were fabricated by the screen printing method, and their polarization characteristics and microstructure parameters are evaluated. Cathode overpotentials were measured at the measurement condition of 700 °C and 100 % O2. Microstructures were reconstructed by focused ion beam-scanning electron microscope (FIB-SEM). The relationship between polarization characteristics and microstructure is quantitatively investigated.

Numerical Simulation of LSCF-GDC Composite Cathodes with Various Microstructures

“…In the present study, LSCF and LSCF-GDC composite cathodes (19) are used for the 3D reconstruction. The LSCF and the GDC powders are mixed with volume ratios of 100:0 and 50:50, respectively.…”

“…Local reaction current is considered as the summation of DPB and TPB reactions. In the present study, DPB and TPB reaction currents are modeled as (19):…”

“…Enhancement of the effective ionic conductivity of the electrodes is a reasonable approach to improve electrode performance and durability (18)(19)(20)(21)(22)(23). Murray et al (18) demonstrated that addition of GDC to LSCF cathodes can reduce the interfacial resistance.…”

“…Murray et al (18) demonstrated that addition of GDC to LSCF cathodes can reduce the interfacial resistance. Kim et al (19) suggested that GDC addition to LSCF improves electrochemical performance by increasing the TPB density inside the microstructure. Nagato et al (20) investigated the electrochemical effects of YSZ pillars inside the Ni-YSZ anode, and demonstrated that YSZ pillars are very efficient to improve electrode ionic transport.…”

Sm0.5Sr0.5CoO3−δ Surface Modification of La0.6Sr0.4Co0.2Fe0.8O3−δ -Ce0.9Gd0.12−δ Composite Oxygen Electrodes for Solid Oxide Electrochemical Cells

“…A 50:50 weight ratio was chosen since several studies have illustrated the optimal ratio of LSCF to GDC to be around 30 to 50 weight % LSCF. 4,[33][34][35] The infiltration solution was prepared by dissolving Sr(NO 3 ) 2 ·6H 2 O (Sigma-Aldrich), Sm(NO 3 ) 3 ·6H 2 O (Sigma-Aldrich), and Co(NO 3 ) 2 ·xH 2 O (Sigma-Aldrich) in deionized H 2 O along with 2 weight percent Triton X-100 surfactant. Electrodes were infiltrated four times with 1 μl of 2 M solution, placed under vacuum, and fired at 450 °C for 30 min after each infiltration.…”