Long-Term Electric Conductivity of (Nb,Y)-Doped Bi2O3 Solid Electrolytes for Solid Oxide Fuel Cells
Two oxides, Y2O3 and Nb2O5, were doped into Bi2O3-based electrolyte in a composition of (Bi 1-x-y,Nb x,Y y)2O 3, where (x+y)=0.12 to 0.2 and the x:y ratio 3:1 to 1:3. The delta-phase retention, the oxygen vacancy order-disorder transformation, the ionic and electric conductivity were investigated by various techniques. The long-term conductivity of the dense electrolytes was determined showing moderate degradation due to phase transformation possible triggered by surface evaporation of Bi-oxide. The best retention of the conductivity is about 60% after 300 hr test.
S.T. Tu, G.Z. Wang and J.M. Gong
W. C. J. Wei, "Long-Term Electric Conductivity of (Nb,Y)-Doped Bi2O3 Solid Electrolytes for Solid Oxide Fuel Cells", Advanced Materials Research, Vol. 509, pp. 111-113, 2012