A perovskite nanocomposite and self-assembled nanoparticle-decorated cathode for low temperature SOFCs

Abstract

One-pot route synthesis of an A-site Sm-doped simple perovskite with nominal composition Sm_0.10Ba_0.90Co_0.8Fe_0.2O_3−δ leads to a novel perovskite nanocomposite containing ∼90% A-site cation deficient cubic simple perovskite Ba_0.925(Co/Fe)_0.962Sm_0.038O_3−δ and ∼10% orthorhombic layered perovskite SmBa(Co/Fe)₂O_5+δ. The synergy of the two phases in the nanocomposite results in high electrochemical kinetic properties at low temperatures. With the novel perovskite nanocomposite, a surface nanoparticle-decorated nanocomposite cathode is self-assembled through a one-step sintering process. The corresponding anode-supported cell delivers a peak power density of 1271 mW cm⁻² at 650 °C. The cell also demonstrates long-term stability (∼333 h) under a current load of 600 mA cm⁻² and shows short-term stability (∼16 h) under an alternating large current load between 600 and 1700 mA cm⁻² at 600 °C. The novel perovskite nanocomposite developed in this paper is among the best in open literature for cathodes of low temperature SOFCs.