Electrochemical investigations of cobalt-free perovskite cathode material for intermediate temperature solid oxide fuel cell

Abstract

A novel cobalt-free perovskite zinc-doped lanthanum strontium iron oxide (La0.8Sr0.2ZnxFe1−xO3−δ, LSZF, x = 0.1–0.3) is synthesized and evaluated as cathode material for intermediate temperature solid oxide fuel cell (IT-SOFC) with samarium doped ceria (SDC) electrolyte. LSZF cathode at x = 0.2 composition demonstrates the remarkable electrochemical activity at intermediate temperature (550 °C): such as, high electrical conductivity (13.63 S cm−1), excellent thermal stability with SDC electrolyte (12.10 μK−1), high surface area (4.52 m2 g−1), extremely reduced area specific resistance (0.69 Ω cm−2) and low activation energy (0.117 eV). Furthermore, single fuel cells are fabricated using LSZF as a cathode, which exhibits the excellent performance by achieving the high power density of 409 mW cm−2 under natural gas as a fuel and ambient air as an oxidant at 550 °C with good stability over 10 h. All experimental results indicate that the LSZF is a promising cathode material for natural gas based intermediate temperature fuel cell applications.