High oxide ion conductivity in Bi2MoO6 oxidation catalyst

Abstract

Both the low (γ)- and high (γ′)-temperature polymorphs of Bi2MoO6 are oxide ion conductors. The γ′ conductivity at 300°C is comparable to that of yttria-stabilized zirconia (YSZ) while its activation energy, 0.510(2) eV, is much less than that of YSZ, 0.79 eV, and is lower than that of the best low temperature oxide ion conductor, BIMEVOX: Bi2V0.9Cu0.1O5.35, 0.56 eV, thus suggesting that γ′-Bi2MoO6 contains a small number of highly mobile oxide ions. This may account for its usefulness as an oxidation catalyst.