Papers by Keyword: H⁺ Conduction

Abstract: In this work ion conductivity and FC application were studied for the new type composite material based on SDC (samarium doped ceria) and Li2SO4. Significant conductivity enhancement was achieved, e.g. 10-2 – 0.4 Scm-1 for the SDC-Li2SO4 compared to 10-4 -10-2 Scm-1 for the SDC between 400 and 650°C. Some ion conductivity mechanisms were proposed correspondingly. Using the SDC-Li2SO4 composite materials as the electrolytes, we achieved high performances, 200-540 mWcm-2, for intermediate temperature (450-650°C) solid oxide FC (ITSOFC) applications. Sulfates, typically Li2SO4, have an excellent chemical stability in sulfur containing atmosphere. The sulfate-ceria (SDC-Li2SO4) composite materials can thus meet the demands to develop the sulfur tolerant and H2S FC technologies, which was also demonstrated successfully with significant importance for both fundamental and applied research.

Abstract: Our developments on ceramic composite conductors have experienced about 15 years from the oxyacid-salts oxide proton-based conductors, non-oxide containment salts, the ceria-based composite electrolytes, hybrid proton and oxygen ion conductors and nano-composites. A special emphasis is paid to new functional nano-composites based on hybrid proton and oxygen ion conductors that have demonstrated advanced properties and fuel cell applications, e.g., excellent ionic conductivity of 0.01 to 1 Scm-1 and performances of 200 - 1000 mWcm-2 for temperatures achieved for fuel cells between 400 and 700°C. Some proton and oxygen ion conducting mechanisms in the materials are reviewed and discussed. The hybrid ion conduction and dual electrode reactions and processes create a new generation fuel cell system.