Low-temperature sintering and electrical properties of strontium- and magnesium-doped lanthanum gallate with V_2O_5 additive

摘要

The effects of a V_2O_s additive on the low-temperature sintering and ionic conductivity of strontium-and magnesium-doped lanthanum gallate (LSGM: La_(0.8)Sr_(0.2)Ga_(0.8)Mg_(0.2)O_(2.8) are studied. The LSGM powders prepared by the glycine nitrate method are mixed with 0.5-2 at.% of V0_(s/2) and then sintered at 1100-1400℃ in air for 4 h. The apparent density and phase purity of the LSGM specimens are increased with increasing sintering temperature and VO_(5/2)concentration due to the enhanced sintering and mass transfer via the intergranular liquid phase. The 1 at.% VO_(5/2)-doped LSGM specimen sintered at 1300 C exhibits a high oxide ion conductivity of ~0.027Scm~(-1) at 700℃ over a wide range of oxygen partial pressure (P_o_2 = 10~(-27) - 1 atm), thereby demonstrating its potential as a useful electrolyte for anode-supported solid oxide fuel cells (SOFCs) without the requirement for any buffer layer between the electrolyte and anode.