Mechanical Engineering Commons^™

Sr‐ And Ni‐Doped Lacoo3 And Lafeo3 Perovskites: New Cathode Materials For Solid‐Oxide Fuel Cells, Kevin Huang, Hee Y. Lee, John B. Goodenough

Faculty Publications

An improved cathode material for a solid‐oxide fuel cell would be a mixed electronic and oxide‐ion conductor with a good catalytic activity for oxygen reduction at an operating temperature T _op ≥ 700°C and a thermal expansion matched to that of the electrolyte and interconnect. We report on the properties of Sr‐ and Ni‐doped LaCoO₃ and LaFeO₃ perovskites that meet these criteria. Single‐phase regions were determined by X‐ray diffraction, and thermogravimetric analysis measurements were used to obtain the temperatures above which oxygen loss, and hence oxide‐ion conductivity, occurs. The conductivity and Seebeck measurements indicate the coexistence of both …