Co-improving the electrocatalytic performance and H2S tolerance of a Sr2Fe1.5Mo0.5O6−δ based anode for solid oxide fuel cells

Abstract

Co-improving the structural stability and electrocatalytic activity of anode materials is a major challenge for the development of solid oxide fuel cells (SOFCs). Herein, a novel anode material Sr₂Fe_1.5Mo_0.4Ti_0.1O_6−δ (SFMT) is designed and prepared by using Ti to replace Mo of Sr₂Fe_1.5Mo_0.5O_6−δ (SFM). Ti doping effectively enhances the ability of SFM to resist H₂S corrosion and SFMT maintains the desired perovskite structure after being exposed to H₂S (1000 ppm). Moreover, the partial replacement of Mo⁵⁺/Mo⁶⁺ by Ti⁴⁺ ions can also improve the concentration of oxygen vacancies and enhance the oxygen ion surface exchange and bulk diffusion capabilities. The SFMT-based SOFC delivers an excellent power output in H₂ containing 500 ppm H₂S and stably operates for a long time (>50 h), resulting in a maximum power density of 0.71 W cm⁻² at 800 °C. The current study presents a promising material design strategy for developing high-performance SOFC anodes.