Electrochemical performance of sol-gel derived La0.6Sr0.4CoO3-δ cathode material for proton-conducting fuel cell: A comparison between simple and advanced cell fabrication techniques

Abstract

In this study, the effects of different fabrication techniques on the electrochemical performance of solgel derived La0.6Sr0.4CoO3-δ (LSC) cathode material for intermediate temperature proton-conducting fuel cells were investigated. Single-phase, sub-micron LSC powder was used to prepare cathode slurries by a simple grinding-stirring (G-S) technique and an advanced ball milling-triple roll milling (BM-TRM) technique. The prepared G-S and BM-TRM cathode slurries were brush painted and screen printed, respectively, onto separate BaCe0.54Zr0.36Y0.1O2.95 (BCZY) proton-conducting electrolytes to fabricate symmetrical cells of LSC|BCZY|LSC. The thickness of LSC cathode layer prepared by brush painting and screen printing was 17 ± 0.5 μm and 7 ± 0.5μm, and the surface porosity of the layers was 32% and 27%, respectively. Electrochemical impedance spectroscopy analysis revealed that the layer deposited by screen printing had lower area specific resistance measured at 700 °C (0.25 cm2) than the layer prepared by brush painting of G-S slurry (1.50 cm2). The enhanced LSC cathode performance of the cell fabricated using BM-TRM assisted with screen printing is attributed to the improved particle homogeneity and network in the prepared slurry and the enhanced particle connectivity in the screen printed film.