Development and understanding of La0.85Sr0.15Cr1-xNixO3-delta anodes for La5.6WO11.4-delta-based Proton Conducting Solid Oxide Fuel Cells

Abstract

[EN] Porous electrodes based on the system La0.85Sr0.15Cr1-xNixO3-delta (x = 0.1 and 0.2) have been investigated as anodes for proton conducting solid oxide fuel cells based on the La5.6WO11.4-delta (LWO) electrolyte material. The microstructure of the anodes was optimized by varying both the starting powder morphology and the final anode sintering temperature. Two different electrode thicknesses were studied, i.e. 15 and 30 gm. The importance of the catalytic role of Ni was also studied by using different concentrations of Ni (10% and 20%) in the chromite and by tuning the Ni particle sizes through the control of the reduction temperature. Additionally, a ceramic-ceramic (cer-cer) composite electrode comprising a physical mixture of the optimized chromite and LWO phase was also considered. Finally, a kinetics study and modeling based on Langmuir-Hinshelwood mechanism was carried out in order to quantitatively describe the rate of dissociative adsorption of H-2 on the Ni particles spread on the chromite surface.