Anion Doping: A New Strategy for Developing High-Performance Perovskite-Type Cathode Materials of Solid Oxide Fuel Cells

3 years ago

Anion Doping: A New Strategy for Developing High-Performance Perovskite-Type Cathode Materials of Solid Oxide Fuel Cells

Yinlong Zhu, Zongping Shao, Wei Zhou, Zhenbao Zhang, Yijun Zhong

Overcoming the sluggish activity of cathode materials is critical to realizing the wide-spread application of intermediate-temperature solid oxide fuel cells. Herein, a new way is reported to tune the performance of perovskite-type materials as oxygen reduction electrodes by embedding anions (F−) in oxygen sites. The obtained perovskite oxyfluorides SrFeO3−σ−δFσ and SrFe0.9Ti0.1O3−σ−δFσ (σ = 0.05 and 0.10) show improved electrocatalytic activity compared to their parent oxides, achieving area specific resistance values of 0.875, 0.393, and 0.491 Ω cm2 for SrFeO3−δ, SrFeO2.95−δF0.05, and SrFeO2.90−δF0.10, respectively, at 600 °C in air. Such improved performance is a result of the improved bulk diffusion and surface exchange properties due to anion doping. Moreover, favorable stability in performance is also demonstrated for the F− anion-doped perovskites as oxygen reduction electrodes at 650 °C for a test period of ≈200 h. A combination of anion doping and cation doping may provide a highly attractive strategy for the future development of cathode materials. A novel and facile strategy toward the development of a high-performance cathode is proposed for the first time to resolve the slow activity of cathode materials by embedding anion ions into the perovskite lattice for intermediate-temperature solid oxide fuel cells.

Publisher URL: http://onlinelibrary.wiley.com/resolve/doi

DOI: 10.1002/aenm.201700242