Improved structural stability and electrochemical performance of 8YSZ electrolyte by M_xO_y doping for low temperature solid oxide fuel cells (LT-SOFCs)

摘要

The role of nanosized metallic oxides (M_xO_y) in phase stability, thermal behavior and electrical conductivity of 8 mol% yttria stabilized zirconia (8YSZ) has been investigated. 8YSZ co-doped with 4 mol% M_xO_y (YSZ-M_xO_y) powders have been elaborated by solid state reaction at 1500 ℃ during 12 h. The ionic conductivity of 8YSZ has been improved by adding CeO_2, ZnO or their mixture CeO_2-ZnO as nanosized stabilizers for ZrO_2 matrix in the temperature field from 400 ℃ to 600 ℃. Finally, the performance evaluation of 200 μm thick film YSZ-M_xO_y as electrolyte for Solid Oxide Fuel Cells (SOFCs) has been discussed. The open circuit voltage has been 1.03 V and the maximum power density has been 440 mW·cm~(-2) at 600 ℃, in the presence of 3.5 mol% CeO_2, 0.5 mol% ZnO and 8 mol% Y_2O_3 co-doped zirconia.