Synthesis and characterization of Fe from different source doped 8YSZ for solid electrolyte in solid oxide fuel cell (SOFC)

Abstract

The samples from different sources of Fe in oxide form (pure iron oxide powders, Fe₂O₃) and Fe source from salt (iron nitrate, Fe(NO₃)₃) for different compositions (pure YSZ, 1FeYSZ, 2FeYSZ and 3FeYSZ) were prepared and sintered at 1550°C. The microstructure, crystal structure and ionic conductivity of pure YSZ and Fe-doped YSZ at different composition were investigated. Pure 8YSZ consists of tetragonal and monoclinic phase while Fe addition in 8YSZ for both sources consists of all tetragonal, cubic and monoclinic. The proportion of tetragonal phase decreased as the composition of increased. The amount of cubic phase tends to decrease with increasing the amount of Fe. 3FeYSZ for both sources of Fe reveal that the addition of Fe significantly enhanced the ionic conductivity of 8YSZ sample. However, 3Fe(p)YSZ has smaller grain resistivity and thus has higher conductivity compared to 3Fe(s)YSZ.