Protonic SOFCs with a novel La0.4K0.1Ca0.5MnO3-? cathode

The La0.4K0.1Ca0.5MnO3-delta (LKCM) material has been successfully prepared by partially replacing La cations with K cations in La0.5Ca0.5MnO3-delta (LCM). The relatively low calcination temperature retained K cations in the lattice. Doping K triggered the cathode activity of the material, and LKCM showed more oxygen vacancies and improved catalytic activity than LCM. Therefore, a proton-conducting solid oxide fuel cell(H-SOFC) using an LKCM cathode exhibited better performance than the LCM cell. Despite the high basicity of K, the incorporation of 10 mol.% K into LCM did not significantly change the chemical stability of the material. LKCM still presented good stability against CO2. First-principles calculations revealed the mechanism for good stability. Further optimizations of the cell structure led to an impressively high fuel cell performance of 1317 mW cm-2 at 700 degrees C for the LKCM cell, which was larger than most H-SOFCs using Mn-based cathodes in literature reports.

Automated summary

The La0.4K0.1Ca0.5MnO3-delta (LKCM) material was successfully prepared by partially replacing La cations with K cations in La0.5Ca0.5MnO3-delta (LCM). Doping K triggered the cathode activity of the material, and LKCM showed more oxygen vacancies and improved catalytic activity than LCM. Therefore, a proton-conducting solid oxide fuel cell (H-SOFC) using an LKCM cathode exhibited better performance than the LCM cell.