In-situ growth of Ru/RuO2 nanoparticles decorated (La0.6Sr1.4)0.95Mn0.9Ru0.1O4 as a potential electrode for symmetrical solid oxide fuel cells

The A-site deficient (La 0.6 Sr 1.4 ) 0.95 Mn 0.9 Ru 0.1 O 4 (LSMRuO 4 ) K 2 NiF 4 -type oxide is developed as a potential electrode for symmetrical solid oxide fuel cells (SSOFCs) with Ru/RuO 2 nanoparticles decorating, which exhibits enhanced electrochemical activity for both hydrogen oxidation reaction (HOR) and oxygen reduction reaction (ORR). The Ru nanoparticles are introduced via in-situ exsolution and distribute uniformly on the surface of LSMRuO 4 as fuel electrode. And the metallic Ru nanoparticles were converted into RuO 2 nanoparticles after exposing furtherly to the conditions encountered at oxygen electrode. Decorated by Ru nanoparticles, the highest electrical conductivity of 10.07 S cm −1 and lowest polarization resistance of 0.28 Ω cm 2 are obtained for LSMRuO 4 in 5% H 2 /N 2 at 750 °C. Additionally, modified by RuO 2 nanoparticles, LSMRuO 4 also exhibits the highest electrical conductivity of 55.23 S cm −1 and lowest polarization resistance of 0.12 Ω cm 2 at 750 °C in air. With Ru nanoparticles at fuel electrode and RuO 2 nanoparticles at oxygen electrode simultaneously, the LSMRuO 4 -SSZ|SSZ|LSMRuO 4 -SSZ (Sc 2 O 3 stabilized ZrO 2 ) single cell demonstrates the highest power output of 711 mW cm −2 at 750 °C using pure H 2 as fuel. All these results indicate that Ru/RuO 2 nanoparticles decorated LSMRuO 4 can be a favorable electrode for SSOFCs.