Unformatted text preview: 0C 1000C 0.79 eV 2 i (S/cm) = 1.63 10 exp ZrO2 in a cubic fluorite structure and maximize oxygen vacancies, as pure YSZ in no kB T
kB = 8.617 10
5 eV/K suitable ion conductor. High electrolyte temperature is required to ensure adequate oxygen ion conduc ity in the solid-state ceramic electrolyte, as oxygen ion mobility is nearly zero below critical light-off temperature in the electrolyte. As a result, conventional SOFCs will produce any significant current until being externally heated to the light-off temperatu Commonly used electrolyte conductivity is nearly zero until around 650 C , althou low-temperature SOFC operation at 500 C using doped ceria (CeO2 ) ceramic and ot electrolytes has shown feasibility . The YSZ has a mixed (electrical and ionic) conductivity, but the electrical conductiv is nearly negligible for typical operating conditions in the SOFC. The ionic and electri conductivity of 8% mole fraction yttria YSZ, (ZrO2 )0.92 (Y2 O3 )0.08 , has been well stud : i S cm = 1.63 102 exp -0.79 eV kB T 5 (5. Tuesday, Novembe...
View Full Document
- Fall '13
- Electrochemistry, Fuel cell, Solid oxide fuel cell, SOFC