Cubic Zr1−xLnxW2−yMoyO8−x/2 (Ln = Er: x = 0.01, 0.02, 0.03; y = 0; Ln = Yb: x =

0.02, 0.03; y = 0.4) solid solutions, well-known negative thermal expansion

materials were prepared by using conventional solid state reactions. The

morphology and the composition of the fracture surfaces of the ceramic pellets

were determined using SEM and EDX. The conductance properties of the pellets,

such as conductivity and conductance activation energy, were studied by AC

impedance spectroscopy and the materials perform clearly oxygen ionic conduction

with the conductivity of about 10−4S/cm at 673K, a comparable value to that of

ceria based solid electrolytes. The substitution of Mo for W enhanced the thermal

stability of ZrW2O8, so that the conductivity of Zr0.98Yb0.02W1.6Mo0.4O7.99 ceramic

can be measured up to 873K, which was about 5.9 x 10−4S/cm.

Oxygen Ionic Conductivity of NTE Materials of Cubic Zr1−xLnxW2−yMoyO8−x/2

(Ln=Er, Yb). H.H.Li, H.T.Xia, X.P.Jing, X.H.Zhao: Solid State Sciences, 2008,

10[8], 1037-41