Investigation of La0.65Ca0.35FeO3−δ as a Co-Free Cathode for Protonic Ceramic Fuel Cells with Yb-Doped BaZrO3 Electrolyte

Abstract

Although cobalt-containing cathode materials are widely used in protonic ceramic fuel cells (PCFCs) because of its high catalytic activity, cobalt diffuses into the proton-conducting electrolyte, thereby decreasing the power generation performance. To achieve a higher power generation performance in PCFCs with a cobalt-free cathode, we fabricate anode-supported PCFCs using BaZr0.8Yb0.2O3–δ as the electrolyte, and composite cathodes of La0.65Ca0.35FeO3−δ (LCaF) and BaZr0.1Ce0.7Y0.1Yb0.1O3−δ (BZCYYb). The mixing weight ratios of LCaF and BZCYYb are varied to 80:20, 70:30, 60:40, 50:50, and 30:70. The PCFC with LCaF–BZCYYb (60:40) composite cathode exhibits the highest power generation performance in the operating temperature range of 500–700 °C with a maximum power density (MPD) of 0.41 W cm−2 at the operating temperature of 600 °C. This MPD value is higher than that obtained in our previous study using a PCFC with a La0.6Sr0.4Co0.2Fe0.8O3−δ –BZCYYb composite cathode.