In Situ Coexsolution of Metal Nanoparticle-Decorated Double Perovskites As Anode Materials for Solid Oxide Fuel Cells

Because of the excellent catalytic activity of nanoparticles, their in situ exsolution on perovskite surfaces has received extensive attention in the field of catalysis. Herein, a unique A- and B-site coexsolved double perovskite, SrBiFeTiO6−δ (SBFT), is used as an anode material in a solid oxide fuel cell (SOFC). A study of its crystal structure confirmed that the cubic structure of the SBFT perovskite has reasonable structural stability under a hydrogen (H2) atmosphere, even though metallic Bi and Fe exsolve from the perovskite lattice. Electrical conductivity results show that the exsolved nanoparticles improve the conductivity of the perovskite. X-ray photoelectron spectroscopy results indicate that the SBFT surface features Ti3+/4+, Fe3+/2+/0, Bi3+/0, and Sr2+ valence states. The output peak power densities of a single cell with SBFT–Ce0.8Sm0.2O1.9 as an anode are 280 and 503 mW cm–2 in ethanol and under a H2 atmosphere at 800 °C, respectively. In ethanol, at 800 °C, the fuel cell is relatively stable for over 30 h under a voltage of 0.5 V. All of the results show that the coexsolving of elements on a perovskite is a promising material design approach for creating SOFC anodes that have excellent properties.