Ni–La2O3 cermet hydrogen electrode originating from the in-situ decomposition of the La2NiO4+δ oxide for quasi-symmetrical solid oxide fuel cells

Abstract

Ni–La2O3 cermet hydrogen electrode having almost no ionic conductivity still exhibits excellent electrochemical performance owing to the hydrogen spillover process from high hydrogen adsorption capability on the La2O3 surface. In this work, we develop Ni–La2O3 cermet hydrogen electrode originating from the in-situ decomposition of the La2NiO4+δ(LNO) oxide, and then perform the electrochemical properties for quasi-symmetrical solid oxide fuel cells (Q-SSOFCs), which own YSZ electrolyte support wrapped GDC barrier layer. The area specific resistance (ASR) of LNO air electrode increases from 2.09 to 7.41 Ω cm2, with the temperature of decreasing from 800 to 600 °C. The electrochemical performances of Q-SSOFCs with Ni–La2O3 cermet hydrogen electrode and LNO air electrode are characterized, and the values of the peak power density and the electrode polarization resistance (Rp) of the symmetrical electrodes measured at 800 °C are 245.18 mW cm−2 and 0.61 Ω cm2. These results indicate that the hydrogen spillover process of Ni–La2O3 cermet hydrogen electrode can greatly promote the hydrogen oxidation reaction.