Ex-solution of Ni nanoparticles in a La0.2Sr0.8Ti1−xNixO3−δ alternative anode for solid oxide fuel cell

Abstract

Abstract Electro-catalytic nanoparticles can be produced in oxide anodes for solid oxide fuel cell (SOFC) by an ex-solution method, i.e., by incorporating metals into a perovskite oxide phase in air followed by the reduction of the perovskite oxide. In this study, we used a Ni ex-solution method with a La and Ni co-doped SrTiO 3 (La 0.2 Sr 0.8 Ti 1 − x Ni x O 3 − δ , x = 0–0.2) anode for SOFC. The parameters and mechanisms of the Ni ex-solution were investigated by varying the ex-solution temperature (800–1300 °C) and time (3–24 h). The degrees of Ni ex-solution and Ti reduction were dependent on time and temperature. Ni ex-solution reaction was relatively faster than Ti reduction which required a higher temperature or a longer time. XRD analysis was used to observe the changes in the lattice parameter of La 0.2 Sr 0.8 Ti 1 − x Ni x O 3 − δ after the ex-solution process. The electrochemical performance of an electrolyte (Sc-stabilized zirconia)-supported cell with the La 0.2 Sr 0.8 Ti 1 − x Ni x O 3 − δ anode with x = 0.1 showed that the total cell resistance is high, due mostly to the anode resistance. The maximum power density at 800 °C is also relatively low, ~ 150 mW/cm 2 , due to the thick (~ 300 μm) electrolyte and the low level of anodic performance.