LaNi0.6Co0.4−xFexO3−δ as Air-Side Contact Material for La0.3Ca0.7Fe0.7Cr0.3O3−δ Reversible Solid Oxide Fuel Cell Electrodes

Abstract

The goal of the current work was to identify an air-side-optimized contact material for La0.3Ca0.7Fe0.7Cr0.3O3−δ (LCFCr) electrodes and a Crofer22APU interconnect for use in reversible solid oxide fuel cells (RSOFCs). LaNi0.6Co0.4−xFexO3 (x = 0–0.3) perovskite-type oxides were investigated in this work. The partial substitution of Co by Fe decreased the thermal expansion coefficient values (TEC) closer to the values of the LCFCr and Crofer 22 APU interconnects. The oxides were synthesized using the glycine–nitrate method and were characterized using X-ray thermodiffraction and 4-probe DC electrical conductivity measurements. Based on the materials characterization results from the Fe-doped oxides investigated here, the LaNi0.6Co0.2Fe0.2O3−δ composition was selected as a good candidate for the contact material, as it exhibited an acceptable electrical conductivity value of 395 S·cm−1 at 800 °C in air and a TEC value of 14.98 × 10−6 K−1 (RT-900 °C).

Machine-learning prediction of thermal expansion coefficient for perovskite oxides with experimental validation

“…The perovskite structure is very versatile, which enables them to perform excellently in several high-interest applications, including high temperature technologies such as solid oxide fuel cells (SOFCs), and solid oxide electrolysis cells (SOECs). [5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20][21][22] In these high temperature applications one of the properties that is essential to performance is the thermal expansion coefficients (TECs) of the materials used for certain device components. Thermal expansion coefficients are proportionality constants of how a material expands or contracts with a change in temperature.…”